Parasitism: Wikis

  
  
  
  
  

Did you know ...


More interesting facts on Parasitism

Include this on your site/blog:

Encyclopedia

From Wikipedia, the free encyclopedia

.Parasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the host.^ Differences between totalizts and parasites: .
  • Parasitism - the philosphy of immorality, stagnation, aggression and unhappiness (in English) 3 February 2010 17:22 UTC www.anzwers.org [Source type: Original source]

^ This is obviously one of the bad types of parasites.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ In addition, he detailed the behavioral specializations that permit the parasitic nestling to prosper in the nest of the host, often at the expense of the true offspring of the nest owner.
  • Biographical Memoirs V.62 3 February 2010 17:22 UTC www.nap.edu [Source type: Academic]

.In general, parasites are much smaller than their host, show a high degree of specialization for their mode of life, and reproduce more quickly and in greater numbers than their hosts.^ The following epidemic is therefore much smaller, with a greater density of hosts surviving to reproduce.
  • PLoS ONE: The Population Dynamical Implications of Male-Biased Parasitism in Different Mating Systems 3 February 2010 17:22 UTC www.plosone.org [Source type: Academic]

^ These parasites can do much more than that and the process in which they do this in is amazing.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ There are more species of parasite than there are host species.
  • Worms and Parasites in humans and animals: natural herbal treatments 31 January 2010 13:48 UTC www.shirleys-wellness-cafe.com [Source type: FILTERED WITH BAYES]

.Classic examples of parasitism include interactions between vertebrate hosts and diverse animals such as tapeworms, flukes, the Plasmodium species, and fleas.^ Depending on the species which acts as the vector, the worm will then begin a new life cycle in the animal host and the cycle of infection will continue-assuring the perpetuation of the species.
  • Parasites 31 January 2010 13:48 UTC www.herbs2000.com [Source type: FILTERED WITH BAYES]

^ The three examples he gives are a parasitic wasp which can brilliantly perform a “brain surgery” to control a roaches mind, a parasitic nematode which can cleverly get their way into their host to reproduce, and the blood fluke who can stay inside their host for years and years.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ Host and microhabitat specificity, for example, may be affected by the age of host and parasite, presence or absence of other competitive parasite species, and the numbers of parasite individuals present.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.Parasitism is differentiated from parasitoidism, a relationship in which the host is always killed by the parasite such as moths, butterflies, ants, flies, elietes and humans and also others.^ Hasegawa E: Phylogeny and host-parasite relationships in social parasitism in Lasius ants.
  • BioMed Central | Full text | A DNA and morphology based phylogenetic framework of the ant genus Lasius with hypotheses for the evolution of social parasitism and fungiculture 3 February 2010 17:22 UTC www.biomedcentral.com [Source type: Academic]

^ This explains why N. fowleri attacks are so rapidly fatal—since hosts are not necessary to its survival, the parasite does not have to take pains to avoid killing them.
  • Damn Interesting • A Fluke of Nature 31 January 2010 13:48 UTC www.damninteresting.com [Source type: FILTERED WITH BAYES]

^ In its award-winning documentary, The Body Snatchers , National Geographic magazine reported: "In fact, parasites have killed more humans than all the wars in history."

.The harm and benefit in parasitic interactions concern the biological fitness of the organisms involved.^ As we stated above, the broad definition of a parasite is any organism that is dependent on another (the host) for room and board, and does not necessarily cause the host any harm.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ A second type of symbiosis, commensalism, likewise involves a benefit to only one of the two organisms, but in commensalism the beneficiary, or commensal, manages to receive its benefits without causing any detriment to the host.
  • Parasites and Parasitology – FREE Parasites and Parasitology information | Encyclopedia.com: Find Parasites and Parasitology research 18 September 2009 9:27 UTC www.encyclopedia.com [Source type: FILTERED WITH BAYES]

^ Parasite is an organism that lives on or in other organisms from which it obtains nutrients to live and causes harm in the process.
  • Human Intestinal Parasites Worms 31 January 2010 13:48 UTC www.appliedozone.com [Source type: FILTERED WITH BAYES]

.Parasites reduce host fitness in many ways, ranging from general or specialized pathology (such as castration), impairment of secondary sex characteristics, to the modification of host behaviour.^ Modification of intermediate host behaviour by parasites.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ There are many parasites that fit this category.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ A parasite is generally smaller than the host and of a different species.
  • Your Liver , Parasites and the Healing Crisis 31 January 2010 13:48 UTC altered-states.net [Source type: FILTERED WITH BAYES]

.Parasites increase their fitness by exploiting hosts for food, habitat and dispersal.^ The abstraction of foodsubstances from the tissues of the host may be insignificant even if the parasites are numerous, but it is notable that in many cases the effect is not merely that of causing an extra drain on the food-supply of the host which might be met by increased appetite.

^ A human parasite is an organism or animal which lives inside the host human and survives and thrives by either eating the food ingested by the host, or by eating body cells and tissues of the host.

^ The explanation given was that is was a symbiotic relationship in which the parasite gets food and shelter, and the host gets a well-regulated immune system.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

.Although the concept of parasitism applies unambiguously to many cases in nature, it is best considered part of a continuum of types of interactions between species, rather than an exclusive category.^ I have learned many more things than I knew before about parasitic life, and how they are heavily affecting human life.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ Although no-one carried out any research in this area, I personally believe that because of the parasitism dies more people than because of any other illness.
  • Parasitism - the philosphy of immorality, stagnation, aggression and unhappiness (in English) 3 February 2010 17:22 UTC www.anzwers.org [Source type: Original source]

^ Many parasites may be considered as harmless or even necessary for their hosts.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.Particular interactions between species may satisfy some but not all parts of the definition.^ Because the relationship between the sexual and asexual phases is not always apparent, a particular species of fungi may have two names until someone discovers that the two phases occur in the same organism.

^ The Tapeworm genus Hymenolepis contains in excess of 400 species (according to some authorities), virtually all of which are found in higher vertebrates.
  • Parasite symptoms 31 January 2010 13:48 UTC www.shanti.com.au [Source type: FILTERED WITH BAYES]

^ Indeed, some species have become so well adapted to live in the human intestine that the host (man) may be entirely asymptotic."

In many cases, it is difficult to demonstrate that the host is harmed. .In others, there may be no apparent specialization on the part of the parasite, or the interaction between the organisms may be short-lived.^ If not there is no chance of getting parasites.

^ No parasitism of any other weevil species was observed.
  • BIREA: Entomophagous biological control agents 3 February 2010 17:22 UTC www.b3nz.org [Source type: Academic]

^ Other species of Isospora may be present.
  • Parasites - Internal 31 January 2010 13:48 UTC maxshouse.com [Source type: FILTERED WITH BAYES]

.In medicine, only eukaryotic organisms are considered parasites, with the exclusion of bacteria and viruses.^ Getting rid of all these parasites would be absolutely impossible using clinical medicines that can kill only one or two parasites each.
  • Worms and Parasites in humans and animals: natural herbal treatments 31 January 2010 13:48 UTC www.shirleys-wellness-cafe.com [Source type: FILTERED WITH BAYES]
  • Herbal parasite cleans-parasite cleans, cleansing parasites with black walnut,wormwood and cloves 18 September 2009 9:27 UTC www.curezone.com [Source type: General]

^ Drugs should not be considered the only means of attacking parasites.
  • Alternative-Doctor Parasites prevention cure alternative remedies 31 January 2010 13:48 UTC www.alternative-doctor.com [Source type: FILTERED WITH BAYES]

^ Unfortunately most parasite cleanse products not only cause disruptive side effects but are limited in their effectiveness, targeting only one particular parasitic organism in limited areas of the body.
  • Purify Parasite Cleanse. Help rid parasites today, with the premium 100% natural parasite cleanse. 31 January 2010 13:48 UTC www.thelifetree.com [Source type: Original source]

.Some branches of biology, however, regard members of these groups as parasitic.^ In addition, he provides detail on some of the difficulties that guard members -- some of whom were themselves victims of the flooding -- encountered while carrying out these tasks.
  • Flood Exhibit Guide 17 January 2010 8:39 UTC www.mnstate.edu [Source type: FILTERED WITH BAYES]

^ Because supergroups E and H cluster in this major group of the tree [A, B, E, H], we can further hypothesize that these two taxa are or were ancestrally reproductive parasites.
  • Parasitism and Mutualism in Wolbachia: What the Phylogenomic Trees Can and Cannot Say -- Bordenstein et al. 26 (1): 231 -- Molecular Biology and Evolution 3 February 2010 17:22 UTC mbe.oxfordjournals.org [Source type: Academic]

^ Age, sex, strain of T. gondii, and number of parasites may account for some of these differences.
  • Parasites - Internal 31 January 2010 13:48 UTC maxshouse.com [Source type: FILTERED WITH BAYES]

[citation needed]
Mites parasitising a harvestman

Contents

Types of parasitism

Flea bites on a human.
.Parasites are classified based on their interactions with their hosts and on their life cycles.^ On host life-history response to parasitism.
  • Asexual Reproduction in Pygospio elegans Claparede (Annelida, Polychaeta) in Relation to Parasitism by Lepocreadium setiferoides (Miller and Northup) (Platyhelminthes, Trematoda) -- MCCurdy 201 (1): 45 -- The Biological Bulletin 3 February 2010 17:22 UTC www.biolbull.org [Source type: Academic]

^ Host life history responses to parasitism.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Another law of nature is that the parasite, not only by sucking off the life sustenance of the host, but also by altering its life cycle, will inevitably kill the host.
  • The World Order a Study in the Hegemony of Parasitism 3 February 2010 17:22 UTC www.scribd.com [Source type: FILTERED WITH BAYES]

Those that live on its surface are called ectoparasites (e.g. some .mites) and those that live inside the host are called endoparasites (e.g.^ When they are not on a host we call them 'free-living.'
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ A human parasite is an organism or animal which lives inside the host human and survives and thrives by either eating the food ingested by the host, or by eating body cells and tissues of the host.

^ Other parasites move to the inner cabins of the host and are called endoparasites (endo=in).
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

hookworms). .Endoparasites can exist in one of two forms: intercellular (inhabiting spaces in the host’s body) or intracellular (inhabiting cells in the host’s body).^ A human parasite is an organism or animal which lives inside the host human and survives and thrives by either eating the food ingested by the host, or by eating body cells and tissues of the host.

^ Perhaps while a Flood infection form takes over the hosts body and suppresses their consciousness, the infection form also extracts the basic memories of their hosts.
  • Halo Story Page | Story Elements | The Flood 17 January 2010 8:39 UTC halostory.bungie.org [Source type: Original source]

^ When the Flood's inability to suitably care for the host body has caused sufficient degeneration, the Worker/Soldier class will also change into the Carrier form.
  • Halo Story Page | Story Elements | The Flood 17 January 2010 8:39 UTC halostory.bungie.org [Source type: Original source]

.Intracellular parasites, such as bacteria or viruses, tend to rely on a third organism which is generally known as the carrier or vector.^ We presented an extensive, evolutionary analysis of mutualism and parasitism in W. pipientis endosymbionts, widespread intracellular bacteria of arthropods and filarial nematodes.
  • Parasitism and Mutualism in Wolbachia: What the Phylogenomic Trees Can and Cannot Say -- Bordenstein et al. 26 (1): 231 -- Molecular Biology and Evolution 3 February 2010 17:22 UTC mbe.oxfordjournals.org [Source type: Academic]

^ Fleas or louse on dogs and cats should be eliminated as they transmit not only bacteria, viruses but also parasites.
  • Parasites and Pathogenic Protoz 31 January 2010 13:48 UTC www.ourfood.com [Source type: Academic]

^ A parasite is an organism that lives off the life force of another organism, such as an animal or a human.
  • Purify Parasite Cleanse. Help rid parasites today, with the premium 100% natural parasite cleanse. 31 January 2010 13:48 UTC www.thelifetree.com [Source type: Original source]

The vector does the job of transmitting them to the host. .An example of this interaction is the transmission of malaria, caused by a protozoan of the genus Plasmodium, to humans by the bite of an anopheline mosquito.^ As few as ten of the microscopic Giardia protozoan parasite organisms in a glass of water could cause a severe case of giardiasis in the human who drinks it.

^ Cryptosporidiosis is an infection of the epithelial tissue in the upper digestive tract caused by a microscopic human parasite of the genus Cryptosporidium .

^ Their work was a little delayed after Stratman-Thomas developed malaria following a bite from one of the experimental mosquitoes.
  • Development of parasite immmunology 3 February 2010 17:22 UTC www.priory.com [Source type: Academic]

.An epiparasite is one that feeds on another parasite.^ The transport host is really a way for the immature parasite to get from one mammalian host to another.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ The parasite does not develop within the transport host, but is just transferred from one host to another.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ Social parasitism implies that one eusocial species depends on the labour force of another [ 13 - 15 ].
  • BioMed Central | Full text | A DNA and morphology based phylogenetic framework of the ant genus Lasius with hypotheses for the evolution of social parasitism and fungiculture 3 February 2010 17:22 UTC www.biomedcentral.com [Source type: Academic]

.This relationship is also sometimes referred to as hyperparasitism which may be exemplified by a protozoan (the hyperparasite) living in the digestive tract of a flea living on a dog.^ Sleep deprivation is known to cause mental breakdown and hallucinations sometimes referred to as schizophrenia; hence in vulnerable people mental problems may be initiated.
  • drugs, smoking and addiction - abelard 3 February 2010 17:22 UTC www.abelard.org [Source type: Original source]

^ If the cat lives in a flea-infested environment, reinfection with tapeworms may occur in as little as two weeks.
  • Parasites - Internal 31 January 2010 13:48 UTC maxshouse.com [Source type: FILTERED WITH BAYES]

^ The larvae may penetrate through the digestive tract into the muscle of the second host.
  • Parasites and Pathogenic Protoz 31 January 2010 13:48 UTC www.ourfood.com [Source type: Academic]

A female Catolaccus grandis wasp is attracted by a boll weevil larva.
.Parasitoids are organisms whose larval development occurs within another organism's body, resulting in the death of the host.^ HOST: That organism which is necessary for the development of a parasite.
  • PARASITES 31 January 2010 13:48 UTC www.cbu.edu [Source type: Academic]
  • PARASITES 18 September 2009 9:27 UTC www.cbu.edu [Source type: Academic]

^ In a broad sense, a parasitic relationship is defined as one in which one organism (the parasite) lives on or within the other (host), and may cause the host harm.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ A parasite is regarded as an organism that derives nourishment by feeding on or within another animal.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

[1] .Thus, the interaction between the parasitoid and the host is fundamentally different from true parasites and their host, and shares some characteristics with predation.^ Differences between totalizts and parasites: .
  • Parasitism - the philosphy of immorality, stagnation, aggression and unhappiness (in English) 3 February 2010 17:22 UTC www.anzwers.org [Source type: Original source]

^ He concludes by placing all parasites within a shared evolutionary framework, with the host immune response as a constant and powerful selective factor.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ The most closely related genus appears to be Grassenema, a parasite of Procavia, but the differences between the 2 genera are very distinct.

.Social parasites take advantage of interactions between members of social organisms such as ants or termites.^ Buschinger A: Evolution of social parasitism in ants.
  • BioMed Central | Full text | A DNA and morphology based phylogenetic framework of the ant genus Lasius with hypotheses for the evolution of social parasitism and fungiculture 3 February 2010 17:22 UTC www.biomedcentral.com [Source type: Academic]

^ Sumner S, Aanen DK, Delabie J, Boomsma JJ: The evolution of social parasitism in Acromyrmex leaf-cutting ants: a test of Emery's rule.
  • BioMed Central | Full text | A DNA and morphology based phylogenetic framework of the ant genus Lasius with hypotheses for the evolution of social parasitism and fungiculture 3 February 2010 17:22 UTC www.biomedcentral.com [Source type: Academic]

^ Sanetra M, Buschinger A: Phylogenetic relationships among social parasites and their hosts in the ant tribe Tetramoriini (Hymenoptera: Formicidae).
  • BioMed Central | Full text | A DNA and morphology based phylogenetic framework of the ant genus Lasius with hypotheses for the evolution of social parasitism and fungiculture 3 February 2010 17:22 UTC www.biomedcentral.com [Source type: Academic]

.In kleptoparasitism, parasites appropriate food gathered by the host.^ A human parasite is an organism or animal which lives inside the host human and survives and thrives by either eating the food ingested by the host, or by eating body cells and tissues of the host.

^ The explanation given was that is was a symbiotic relationship in which the parasite gets food and shelter, and the host gets a well-regulated immune system.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ They are not required by parasitic animals which live a relatively sheltered existence on or inside the bodies of their hosts amid a relative abundance of food."
  • Res_Opp_ideol-5-Parasitism 3 February 2010 17:22 UTC www.amfirstbooks.com [Source type: Original source]

.An example is the brood parasitism practiced by many species of cuckoo and cowbird, which do not build nests of their own but rather deposit their eggs in nests of other species and abandon them there.^ Cuckoos, cowbirds, and other cheats .
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

^ Brood parasitism in birds: Strangers in the nest.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

^ Nesting: The brown-headed cowbird is a brood parasite; no nest is built and the eggs are laid in the nests of other birds (host species).
  • Molothrus ater 3 February 2010 17:22 UTC www.fs.fed.us [Source type: Academic]

.The host behaves as a "babysitter" as they raise the young as their own.^ Unlike common cuckoos, young indigobirds are reared along with their hosts and they mimic the mouth markings of host nestlings (Nicolai, 1964 ; Payne, 1973 b , 1982 ).
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

.If the host removes the cuckoo's eggs, some cuckoos will return and attack the nest to compel host birds to remain subject to this parasitism.^ Parasitic birds and their hosts: Studies in coevolution .
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

^ Inheritance of egg-colour in the ‘parasitic’ cuckoos.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

^ The distribution of conspecific nest parasitism in birds.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

[2] .The cowbird’s parasitism does not necessarily harm its host’s brood; however, the cuckoo may remove one or more host eggs to avoid detection, and furthermore the young cuckoo may heave the host’s eggs and nestlings from the nest.^ Preferred host nests have eggs present.
  • Molothrus ater 3 February 2010 17:22 UTC www.fs.fed.us [Source type: Academic]

^ The parasitic cowbirds and their hosts.
  • Molothrus ater 3 February 2010 17:22 UTC www.fs.fed.us [Source type: Academic]

^ Parasitism does not necessarily result in injury or benefit to the host.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.Parasitism can take the form of isolated cheating or exploitation among more generalized mutualistic interactions.^ Caring for Pets Dog Intestinal Parasites Internal parasites can take several different forms and can affect the health of your dog or puppy.

^ These bacteria occur in diverse eukaryotic hosts and form parasitic and mutualistic interactions that can be evolutionarily stable for hundreds of millions of years.
  • Parasitism and Mutualism in Wolbachia: What the Phylogenomic Trees Can and Cannot Say -- Bordenstein et al. 26 (1): 231 -- Molecular Biology and Evolution 3 February 2010 17:22 UTC mbe.oxfordjournals.org [Source type: Academic]

^ A system is formed by the parasite, the host, and the environment where each one interacts and influences the other subsystem in such a way that any change in one subsystem affects the other two (Ferreira 1973).
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.For example, broad classes of plants and fungi exchange carbon and nutrients in common mutualistic mycorrhizal relationships; however, some plant species known as myco-heterotrophs "cheat" by taking carbon from a fungus rather than donating it.^ This suggests that C. oncophora and C. surnabada are much more common in the north; however, the results may indicate the location of interested collectors rather than the distribution of the two species.
  • Bibliography of Parasites of Bison 31 January 2010 13:48 UTC www.montana.edu [Source type: Academic]

^ Most nematode species are not parasitic, but some common types of parasitic intestinal worm are the pinworm, whipworm, hookworm, and roundworm.

^ They participated to the full in the common English distrust of our cause and our success, and talked and acted for the South rather than for our nation.
  • The World Order a Study in the Hegemony of Parasitism 3 February 2010 17:22 UTC www.scribd.com [Source type: FILTERED WITH BAYES]

Evolutionary aspects

.Biotrophic parasitism is a common mode of life that has arisen independently many times in the course of evolution.^ I have learned many more things than I knew before about parasitic life, and how they are heavily affecting human life.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ Evolution of parasite life history traits: miths and reality.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ M. Broom, G. D. Ruxton, and R. M. Kilner Host life-history strategies and the evolution of chick-killing by brood parasitic offspring Behav.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

.Depending on the definition used, as many as half of all animals have at least one parasitic phase in their life cycles,[3] and it is also frequent in plants and fungi.^ We normally define parasites as orgamisms which cannot survive without their host and have special modifications to their body or their life cycle for this association.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ "Parasitic diseases account for a large proportion of human morbidity and mortality, and doubtlessly contribute significantly to morbidity and mortality among all animal populations as well.
  • Natural Remedies and Holistic Cures to Treat Parasites on Earth Clinic, Your Source for Home Remedies! 18 September 2009 9:27 UTC www.earthclinic.com [Source type: General]

^ Another law of nature is that the parasite, not only by sucking off the life sustenance of the host, but also by altering its life cycle, will inevitably kill the host.
  • The World Order a Study in the Hegemony of Parasitism 3 February 2010 17:22 UTC www.scribd.com [Source type: FILTERED WITH BAYES]

.Moreover, almost all free-living animals are host to one or more parasite taxa.^ Obligatory parasites live on a host all the time.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ When they are not on a host we call them 'free-living.'
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ "Parasitic diseases account for a large proportion of human morbidity and mortality, and doubtlessly contribute significantly to morbidity and mortality among all animal populations as well.
  • Natural Remedies and Holistic Cures to Treat Parasites on Earth Clinic, Your Source for Home Remedies! 18 September 2009 9:27 UTC www.earthclinic.com [Source type: General]

[3]
Restoration of a Tyrannosaurus with parasite infections. A 2009 study showed that holes in the skulls of several specimens might have been caused by Trichomonas-like parasites[4]
.Parasites evolve in response to defense mechanisms of their hosts.^ Overcome Host Defenses: Mechanisms include .
  • PARASITES 31 January 2010 13:48 UTC www.cbu.edu [Source type: Academic]
  • PARASITES 18 September 2009 9:27 UTC www.cbu.edu [Source type: Academic]

^ Host life history responses to parasitism.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ To compensate, martins have evolved their own set of defensive strategies to combat their parasites.
  • Ectoparasites 31 January 2010 13:48 UTC purplemartin.org [Source type: FILTERED WITH BAYES]

.Examples of host defenses include the toxins produced by plants to deter parasitic fungi and bacteria, the complex vertebrate immune system, which can target parasites through contact with bodily fluids, and behavioural defenses.^ Overcome Host Defenses: Mechanisms include .
  • PARASITES 31 January 2010 13:48 UTC www.cbu.edu [Source type: Academic]
  • PARASITES 18 September 2009 9:27 UTC www.cbu.edu [Source type: Academic]

^ He concludes by placing all parasites within a shared evolutionary framework, with the host immune response as a constant and powerful selective factor.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ The accumulation of toxins compromises our immune system and wears the body down leaving us vulnerable to all sorts of maladies.
  • Worms and Parasites in humans and animals: natural herbal treatments 31 January 2010 13:48 UTC www.shirleys-wellness-cafe.com [Source type: FILTERED WITH BAYES]

.An example of the latter is the avoidance by sheep of open pastures during spring, when roundworm eggs accumulated over the previous year hatch en masse.^ Having studied almost no biology in his degree it was during this year (in which he studied hard to accumulate the appropriate knowledge) that Norman developed an interest in biology that was to shape his professional life.
  • Development of parasite immmunology 3 February 2010 17:22 UTC www.priory.com [Source type: Academic]

.As a result of these and other host defenses, some parasites evolve adaptations that are specific to a particular host taxon and specialize to the point where they infect only a single species.^ Each parasite species must have special adaptations that guarantee infection of a host and survival in it.
  • Parasitism (An Introduction to Parasitology) - un knol de Klaus Rohde 3 February 2010 17:22 UTC knol.google.com [Source type: FILTERED WITH BAYES]

^ These parasites can be species specific, so cross infections do not often occur.
  • Freshwater Fish Parasites 31 January 2010 13:48 UTC www.exoticpetvet.net [Source type: FILTERED WITH BAYES]

^ HABITAT-SPECIFIC PARASITE - A parasite that can live in only one specific location on or in its host.
  • Ectoparasites 31 January 2010 13:48 UTC purplemartin.org [Source type: FILTERED WITH BAYES]

.Such narrow host specificity can be costly over evolutionary time, however, if the host species becomes extinct.^ Evolutionary associations of brood parasitic finches ( Vidua ) and their host species: Analyses of mitochondrial DNA restriction sites.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

^ Although few helminth parasites of ruminants are highly host-specific, the majority of those recorded from wild species have domesticated ruminants as their prime hosts.
  • Bibliography of Parasites of Bison 31 January 2010 13:48 UTC www.montana.edu [Source type: Academic]

^ Female lineages are faithful to particular host species over evolutionarily significant time scales in both common cuckoos ( Cuculus canorus ) and indigobirds ( Vidua spp.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

.Thus, many parasites are capable of infecting a variety of host species that are more or less closely related, with varying success.^ There are more species of parasite than there are host species.
  • Worms and Parasites in humans and animals: natural herbal treatments 31 January 2010 13:48 UTC www.shirleys-wellness-cafe.com [Source type: FILTERED WITH BAYES]

^ The fish infected with a parasite is called the host.
  • Freshwater Fish Parasites 31 January 2010 13:48 UTC www.exoticpetvet.net [Source type: FILTERED WITH BAYES]

^ Various stages of this parasite are capable of infecting both the definitive and intermediate hosts.
  • Parasites that can affect your dog abnd cat. 31 January 2010 13:48 UTC cedarwayvet.com [Source type: FILTERED WITH BAYES]

.Host defenses also evolve in response to attacks by parasites.^ On host life-history response to parasitism.
  • Asexual Reproduction in Pygospio elegans Claparede (Annelida, Polychaeta) in Relation to Parasitism by Lepocreadium setiferoides (Miller and Northup) (Platyhelminthes, Trematoda) -- MCCurdy 201 (1): 45 -- The Biological Bulletin 3 February 2010 17:22 UTC www.biolbull.org [Source type: Academic]

^ Host life history responses to parasitism.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ This explains why N. fowleri attacks are so rapidly fatal—since hosts are not necessary to its survival, the parasite does not have to take pains to avoid killing them.
  • Damn Interesting • A Fluke of Nature 31 January 2010 13:48 UTC www.damninteresting.com [Source type: FILTERED WITH BAYES]

.Theoretically, parasites may have an advantage in this evolutionary arms race because of their more rapid generation time.^ Sick Fish Evicting Equine Parasites Grazing peacefully in the sun is heavenly for horses, but horses may eat much more than clover and grass.

^ You may have trouble identifying these skin parasites because the skin may be red and scratched as a result of you itching and scratching it.

^ This host-parasite system was chosen partly because Stoll was keen to demonstrate the generality of his discoveries.
  • Development of parasite immmunology 3 February 2010 17:22 UTC www.priory.com [Source type: Academic]

.Hosts reproduce less quickly than parasites, and therefore have fewer chances to adapt than their parasites do over a given span of time.^ Less than 10 of the Cryptosporidium oocysts are sufficient to cause an infection - and theoretically even one could rather quickly multiply by cell division and soon cause an infection.

^ Parasitic disease is an eventual outcome of a given parasite in a given host from a given population in a certain environment during a particular life co-evolution period of both protagonists.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Genetic parentage analyses suggest that brood parasitic birds are less promiscuous than might be expected given their lack of nesting and parental care behavior.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

.In some cases, a parasite species may coevolve with its host taxa.^ We normally define parasites as orgamisms which cannot survive without their host and have special modifications to their body or their life cycle for this association.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ Host and microhabitat specificity, for example, may be affected by the age of host and parasite, presence or absence of other competitive parasite species, and the numbers of parasite individuals present.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Many parasites may be considered as harmless or even necessary for their hosts.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.In theory, long-term coevolution should lead to a relatively stable relationship tending to commensalism or mutualism, in that it is in the evolutionary interest of the parasite that its host thrives.^ Hosts and helminth parasites: An evolutionary perspective.

^ Parasitic birds and their hosts: Studies in coevolution .
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

^ Symbiosis, commensalism, mutualism and parasitism .
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

.A parasite may evolve to become less harmful for its host or a host may evolve to cope with the unavoidable presence of a parasite to the point that the parasite's absence causes the host harm.^ Alternative responses by hosts to parasites which may be helpful or harmful.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Later in the show, a woman who works with the host talks about her experience with parasites causing her to think that they are bad.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ Richards points out that the presence of volatiles such as water in a mass of rock would make it buoyant, causing it to rise.
  • The Flood of Noah 17 January 2010 8:39 UTC www.ldolphin.org [Source type: Original source]

.For example, although animals infected with parasitic worms are often clearly harmed, and therefore parasitized, such infections may also reduce the prevalence and effects of autoimmune disorders in animal hosts, including humans.^ Alternative responses by hosts to parasites which may be helpful or harmful.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Infections by parasitic worms are called filarial infections.

^ A fearsome parasite, the guinea worm, uses a human host.
  • Alternative-Doctor Parasites prevention cure alternative remedies 31 January 2010 13:48 UTC www.alternative-doctor.com [Source type: FILTERED WITH BAYES]

[5]
.The presumption of a shared evolutionary history between parasites and hosts can sometimes elucidate how host taxa are related.^ Host life history responses to parasitism.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Hosts and helminth parasites: An evolutionary perspective.

^ Host relations of the parasitic cowbirds.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

.For instance, there has been dispute about whether flamingos are more closely related to the storks and their allies, or to ducks, geese and their relatives.^ Prepatent Period: There is one more term related to life cycles that we would like you to be familiar with.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ (Check in "Menu 3" whether there is even a more recent update!
  • Parasitism - the philosphy of immorality, stagnation, aggression and unhappiness (in English) 3 February 2010 17:22 UTC www.anzwers.org [Source type: Original source]

^ For example, does brood parasitism typically originate with the parasitism of closely related hosts species that are more likely to provide appropriate parental care for parasitic chicks?
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

.The fact that flamingos share parasites with ducks and geese is evidence these groups may be more closely related to each other than either is to storks.^ These parasites can do much more than that and the process in which they do this in is amazing.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ The growing body of evidence is supporting the idea that parasitic disease may be an essential factor for AIDS. The theory was based upon three lines of evidence : .
  • Parasites page: worms protozoa amoeba diseases parasitic animals 31 January 2010 13:48 UTC curezone.com [Source type: FILTERED WITH BAYES]

^ You may in fact be taking one or more of these ingredients; however, they may not be in a high enough amount to initially rid the body of parasites, but would be adequate to provide protection against future infection once you clear up the condition.
  • Parasites page: worms protozoa amoeba diseases parasitic animals 31 January 2010 13:48 UTC curezone.com [Source type: FILTERED WITH BAYES]

.Parasitism is part of one explanation for the evolution of secondary sex characteristics seen in breeding males throughout the animal world, such as the plumage of male peacocks and manes of male lions.^ One unexpected result in this analysis is that the Old World brood parasites (tribe Cuculini) fall into two distinct clades.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

^ Their data confirmed identifications based on egg markings and also indicated that each female mated with a single male, but that two females breeding at one site in Japan both mated with the same male.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

^ Other opposing innate traits such as altruism and symbiosis on the one hand and aggression and parasitism on the other require much broader "group" or sociobiological models.
  • Res_Opp_ideol-5-Parasitism 3 February 2010 17:22 UTC www.amfirstbooks.com [Source type: Original source]

.According to this theory, female hosts select males for breeding based on such characteristics because they indicate resistance to parasites and other disease.^ They can serve as intermediate hosts for other parasites (the fish tapeworm).
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ Parasites are a serious public health threat because so few people are talking about them and even fewer people are listening when they are being discussed.
  • Parasites page: worms protozoa amoeba diseases parasitic animals 31 January 2010 13:48 UTC curezone.com [Source type: FILTERED WITH BAYES]

^ The growing body of evidence is supporting the idea that parasitic disease may be an essential factor for AIDS. The theory was based upon three lines of evidence : .
  • Parasites page: worms protozoa amoeba diseases parasitic animals 31 January 2010 13:48 UTC curezone.com [Source type: FILTERED WITH BAYES]

Co-speciation

.In rare cases, a parasite may even undergo co-speciation with its host.^ Many parasites may be considered as harmless or even necessary for their hosts.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ We normally define parasites as orgamisms which cannot survive without their host and have special modifications to their body or their life cycle for this association.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ Many significant remnants in the genome of parasites and hosts are left during the co-evolution process of a host-parasite-environment system.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.One particularly remarkable example of co-speciation exists between the simian foamy virus (SFV) and its primate hosts.^ Host and microhabitat specificity, for example, may be affected by the age of host and parasite, presence or absence of other competitive parasite species, and the numbers of parasite individuals present.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Males of both species, which had been deposited in the National Parasite Collection between 1911 and 1967, were examined to determine their prevalence, geographic distribution, and hosts.
  • Bibliography of Parasites of Bison 31 January 2010 13:48 UTC www.montana.edu [Source type: Academic]

^ Bordenstein and Reznikoff 2005 ), horizontally transfer between host species (Werren et al.
  • Parasitism and Mutualism in Wolbachia: What the Phylogenomic Trees Can and Cannot Say -- Bordenstein et al. 26 (1): 231 -- Molecular Biology and Evolution 3 February 2010 17:22 UTC mbe.oxfordjournals.org [Source type: Academic]

.In one study, the phylogenies of SFV polymerase and the mitochondrial cytochrome oxidase subunit II from African and Asian primates were compared.^ Here we employed two mitochondrial genes ( cytochrome c oxidase subunit I, 16S ribosomal RNA ), comprising 1,265 bp, together with 64 morphological characters, to recover the phylogeny of Lasius by Bayesian and Maximum Parsimony inference after exploration of potential causes of phylogenetic distortion.
  • BioMed Central | Full text | A DNA and morphology based phylogenetic framework of the ant genus Lasius with hypotheses for the evolution of social parasitism and fungiculture 3 February 2010 17:22 UTC www.biomedcentral.com [Source type: Academic]

^ In the present study, in order to clarify the phylogenetic relationship with other species of schistosomes, sequences from the second internal transcribed spacer (ITS2) of the ribosomal gene repeat, part of the 28S ribosomal RNA gene (28S), and part of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene from B. nairi were analyzed.

^ Recent molecular systematic studies, however, require us to increase this tally by one for cuckoos and reduce it by one for African finches.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

[6] Surprisingly, the phylogenetic trees were very congruent in branching order and divergence times. .Thus, the simian foamy viruses may have co-speciated with Old World primates for at least 30 million years.^ Nevertheless parasitic remains have been found in paleontological sites, 1,5 million years old as well as in 500,000 years old preserved organic material (Ferreira et al.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ In his final years, King, still on the take, was exposed as a principal in the $30 million Beauharnais Power Co.
  • The World Order a Study in the Hegemony of Parasitism 3 February 2010 17:22 UTC www.scribd.com [Source type: FILTERED WITH BAYES]

^ I am now fifty and for at least 30 years I remember having parasites.
  • Natural Remedies and Holistic Cures to Treat Parasites on Earth Clinic, Your Source for Home Remedies! 18 September 2009 9:27 UTC www.earthclinic.com [Source type: General]

Ecology

Quantitative ecology

.When considering the distribution of a single parasite species, one finds that they exhibit an aggregated distribution among host individuals, which means that most hosts harbour few parasites, while a few hosts carry the vast majority of parasite individuals.^ Parasites are a serious public health threat because so few people are talking about them and even fewer people are listening when they are being discussed.
  • Parasites page: worms protozoa amoeba diseases parasitic animals 31 January 2010 13:48 UTC curezone.com [Source type: FILTERED WITH BAYES]

^ We normally define parasites as orgamisms which cannot survive without their host and have special modifications to their body or their life cycle for this association.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ Although no-one carried out any research in this area, I personally believe that because of the parasitism dies more people than because of any other illness.
  • Parasitism - the philosphy of immorality, stagnation, aggression and unhappiness (in English) 3 February 2010 17:22 UTC www.anzwers.org [Source type: Original source]

.This poses considerable problems for students of parasite ecology: the use of parametric statistics should be avoided.^ Although Natural Balance can be used on its own as an exceptional detox, anyone wanting to use herbs to eliminate parasites should start by using Natural Balance as a primary cleanse.
  • Alternative-Doctor Parasites prevention cure alternative remedies 31 January 2010 13:48 UTC www.alternative-doctor.com [Source type: FILTERED WITH BAYES]

^ It seems people with the urge to constantly eat ( I had that and thought it psychological - but it seems the parasites are doing this to you) and with digestion problems should start the parasite program.
  • Natural Remedies and Holistic Cures to Treat Parasites on Earth Clinic, Your Source for Home Remedies! 18 September 2009 9:27 UTC www.earthclinic.com [Source type: General]

^ We have used the framework to define hypotheses of the evolution of two outstanding traits, social parasitism and fungiculture, the evolution of which continues to pose riddles to evolutionary biology.
  • BioMed Central | Full text | A DNA and morphology based phylogenetic framework of the ant genus Lasius with hypotheses for the evolution of social parasitism and fungiculture 3 February 2010 17:22 UTC www.biomedcentral.com [Source type: Academic]

.Log-transformation of data before the application of parametric test, or the use of non-parametric statistics is recommended by several authors.^ This program was also used to perform tests for the saturation of substitutions [ 88 ] on the cox1 and 16S rRNA data.
  • BioMed Central | Full text | A DNA and morphology based phylogenetic framework of the ant genus Lasius with hypotheses for the evolution of social parasitism and fungiculture 3 February 2010 17:22 UTC www.biomedcentral.com [Source type: Academic]

^ White squares indicate constraints enforced in constraint analyses using our concatenated data set in order to test the subgenus relationships of W55, H98, and J04.
  • BioMed Central | Full text | A DNA and morphology based phylogenetic framework of the ant genus Lasius with hypotheses for the evolution of social parasitism and fungiculture 3 February 2010 17:22 UTC www.biomedcentral.com [Source type: Academic]

^ Statistical Assessment of the Root We tested the significance of topological differences in phylogenetic trees with different rooting positions using the Shimodaira–Hasegawa (SH) test (Shimodaira and Hasegawa 1999 ).
  • Parasitism and Mutualism in Wolbachia: What the Phylogenomic Trees Can and Cannot Say -- Bordenstein et al. 26 (1): 231 -- Molecular Biology and Evolution 3 February 2010 17:22 UTC mbe.oxfordjournals.org [Source type: Academic]

However, these give rise to further problems.[7] Therefore, modern day quantitative parasitology is based on more advanced biostatistical methods.

Diversity ecology

.Hosts represent discrete habitat patches that can be occupied by parasites.^ Experimental test of parasitoid host finding behavior Two habitat patches occupied by both the butterfly and the parasitoid were divided into 144 and 132 quadrants (2 x 2 m) in the spring of 2001.
  • Wasp behavior leads to uniform parasitism of a host available only a few hours per year -- van Nouhuys and Ehrnsten 15 (4): 661 -- Behavioral Ecology 3 February 2010 17:22 UTC beheco.oxfordjournals.org [Source type: Academic]

^ Life-history responses of hosts after exposure to parasites represent reallocations of energy in ways that increase reproductive success relative to non-responses.
  • Asexual Reproduction in Pygospio elegans Claparede (Annelida, Polychaeta) in Relation to Parasitism by Lepocreadium setiferoides (Miller and Northup) (Platyhelminthes, Trematoda) -- MCCurdy 201 (1): 45 -- The Biological Bulletin 3 February 2010 17:22 UTC www.biolbull.org [Source type: Academic]

^ These ancient events represent the first steps towards a host-parasite way of life although still at the level of molecules.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.A hierarchical set of terminology has come into use to describe parasite assemblages at different host scales.^ DNA viruses actually integrate themselves into the host's genetic code, allowing them to stay dormant for a while, then entering into the lytic cycle described above at an unspecified time.
  • Halo Story Page | Story Elements | The Flood 17 January 2010 8:39 UTC halostory.bungie.org [Source type: Original source]

^ This classification really takes all the characteristics we described above, as well as anatomic features and uses them to organize the parasites by their similarities.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ Nucleotide uptake into liposomes loaded with solely 10 mM ADP was set to 100% (unpublished data) and the transport into the differently loaded liposomes was calculated accordingly.
  • PLoS Biology: Enlightening Energy Parasitism by Analysis of an ATP/ADP Transporter from Chlamydiae 3 February 2010 17:22 UTC www.plosbiology.org [Source type: Academic]

Infrapopulation
All the parasites of one species in a single individual host.
Metapopulation
All the parasites of one species in a host population.
Infracommunity
All the parasites of all species in a single individual host.
Component community
All the parasites of all species in a host population.
Compound community
All the parasites of all species in all host species in an ecosystem.
.The diversity ecology of parasites differs markedly from that of free-living organisms.^ Blood parasites in free-living African elephants.

^ The prospects for biological control of the free-living stages of nematode parasites of livestock.
  • Integrated Parasite Management For Livestock 31 January 2010 13:48 UTC attra.ncat.org [Source type: FILTERED WITH BAYES]

^ A human parasite is an organism or animal which lives inside the host human and survives and thrives by either eating the food ingested by the host, or by eating body cells and tissues of the host.

.For free-living organisms, diversity ecology features many strong conceptual frameworks including Robert MacArthur and E. O. Wilson's theory of island biogeography, Jared Diamond's assembly rules and, more recently, null models such as Stephen Hubbell's unified neutral theory of biodiversity and biogeography.^ Pathological outcomes are therefore the result of many features and are always modulated by the responses of a living being confronting to a non-self element (DuBois 1959).
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ There are many examples in nature of two organisms living in close association with each other.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ More recently many Christian climbing groups have attempted to find the remains of the Ark, all so far without positive results.
  • The Flood of Noah 17 January 2010 8:39 UTC www.ldolphin.org [Source type: Original source]

.Frameworks are not so well-developed for parasites and in many ways they do not fit the free-living models.^ There are many parasites that fit this category.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ When they are not on a host we call them 'free-living.'
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ I have learned many more things than I knew before about parasitic life, and how they are heavily affecting human life.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

.For example, island biogeography is predicated on fixed spatial relationships between habitat patches ("sinks"), usually with reference to a mainland ("source").^ For one thing, each relationship is probably slightly different and for another there are probably examples which straddle some of the boundaries between different 'states'.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ An example in nature would be the relationship between a remora and a shark.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

.Parasites inhabit hosts, which represent mobile habitat patches with dynamic spatial relationships.^ Although there is growing evidence that males tend to suffer higher levels of parasitism than females, the implications of this for the population dynamics of the host population are not yet understood.
  • PLoS ONE: The Population Dynamical Implications of Male-Biased Parasitism in Different Mating Systems 3 February 2010 17:22 UTC www.plosone.org [Source type: Academic]

^ The explanation given was that is was a symbiotic relationship in which the parasite gets food and shelter, and the host gets a well-regulated immune system.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ The parasite-host-environment system is dynamic, with several points of equilibrium.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.There is no true "mainland" other than the sum of hosts (host population), so parasite component communities in host populations are metacommunities.^ There are more species of parasite than there are host species.
  • Worms and Parasites in humans and animals: natural herbal treatments 31 January 2010 13:48 UTC www.shirleys-wellness-cafe.com [Source type: FILTERED WITH BAYES]

^ In addition, he detailed the behavioral specializations that permit the parasitic nestling to prosper in the nest of the host, often at the expense of the true offspring of the nest owner.
  • Biographical Memoirs V.62 3 February 2010 17:22 UTC www.nap.edu [Source type: Academic]

^ Rob Robertson, MD - "There is no other product in a nutritional substance, nor a drug, that has this kind of power and ability to affect our immune system.
  • Worms and Parasites in humans and animals: natural herbal treatments 31 January 2010 13:48 UTC www.shirleys-wellness-cafe.com [Source type: FILTERED WITH BAYES]

.Nonetheless, different types of parasite assemblages have been recognised in host individuals and populations, and many of the patterns observed for free-living organisms are also pervasive among parasite assemblages.^ The podcast discusses many different types of parasites.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ HOST: That organism which is necessary for the development of a parasite.
  • PARASITES 31 January 2010 13:48 UTC www.cbu.edu [Source type: Academic]
  • PARASITES 18 September 2009 9:27 UTC www.cbu.edu [Source type: Academic]

^ When they are not on a host we call them 'free-living.'
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

The most prominent of these is the interactive-isolationist continuum. .This proposes that parasite assemblages occur along a cline from interactive communities, where niches are saturated and interspecific competition is high, to isolationist communities, where there are many vacant niches and interspecific interaction is not as important as stochastic factors in providing structure to the community.^ There are many parasites that fit this category.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ Bird-ectoparasite interactions, nest humidity, and ectoparasite communities structure.
  • Bird Blow Fly - Literature List 3 February 2010 17:22 UTC www.birdblowfly.com [Source type: Academic]

^ As a last note, there may some important additional factors to help define criminality.
  • Res_Opp_ideol-5-Parasitism 3 February 2010 17:22 UTC www.amfirstbooks.com [Source type: Original source]

Whether this is so, or whether community patterns simply reflect the sum of underlying species distributions (no real "structure" to the community), has not yet been established.

Adaptation

.Parasites infect hosts that exist within their same geographical area (sympatric) more effectively.^ In its award-winning documentary, The Body Snatchers , National Geographic magazine reported: "In fact, parasites have killed more humans than all the wars in history."

^ He concludes by placing all parasites within a shared evolutionary framework, with the host immune response as a constant and powerful selective factor.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Recombination within and between the A and B Wolbachia supergroups has been reported previously using Max 2 , and the A and B Wolbachia frequently coinfect the same arthropod hosts (Baldo et al.
  • Parasitism and Mutualism in Wolbachia: What the Phylogenomic Trees Can and Cannot Say -- Bordenstein et al. 26 (1): 231 -- Molecular Biology and Evolution 3 February 2010 17:22 UTC mbe.oxfordjournals.org [Source type: Academic]

.This phenomenon supports the "Red Queen hypothesis - which states that interactions between species (such as host an parasites) lead to constant natural selection for adaptation and counter adaptation."^ We normally define parasites as orgamisms which cannot survive without their host and have special modifications to their body or their life cycle for this association.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ He concludes by placing all parasites within a shared evolutionary framework, with the host immune response as a constant and powerful selective factor.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ In nature, we are familiar with all types of relationships between different species.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

[8] .The parasites track the locally common host phenotypes, therefore the parasites are less infective to allopatric (from different geographical region) hosts.^ Males of both species, which had been deposited in the National Parasite Collection between 1911 and 1967, were examined to determine their prevalence, geographic distribution, and hosts.
  • Bibliography of Parasites of Bison 31 January 2010 13:48 UTC www.montana.edu [Source type: Academic]

^ Submitted to natural selection and/or the inherent properties of a system, the parasite-host-environment system reacts to changes in each subsystem with different responses, according to the features of the stimulus.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ For example, have allopatric populations of a parasitic species independently evolved egg or nestling mimicry of the same host species?
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

.Experiments published in 2002 discuss the analysis of two different snail populations from two different sources- Lake Ianthe and Lake Poerua in New Zealand.^ For the purpose presented here, virulence – the ability to multiply and transmit genes – and pathogenicity – the capacity to induce morbility and mortality in a host population – are two different features.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ He also discusses the only fatalities that occurred in Hendrum related to the flood, when two brothers died in an accident while building a new home after the flood.
  • Flood Exhibit Guide 17 January 2010 8:39 UTC www.mnstate.edu [Source type: FILTERED WITH BAYES]

^ Maori (New Zealand): Long ago, there were a great many different tribes, and they quarrelled and made war on each other.
  • Flood Stories from Around the World 17 January 2010 8:39 UTC www.talkorigins.org [Source type: Original source]

.The populations were exposed to two pure parasites (digenetic trematode) taken from the same lakes.^ Modeling population dynamics of a songbird exposed to parasitism and predation and evaluating management options.
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

^ Nearly one-third of the entire human population has been exposed to this nasty parasite that can sometimes infect the brain.

^ On two new digenetic trematodes from amphibians of Sindh, Pakistan .
  • Information Resources on Amphibians. Parasites: Animal Welfare Information Center 31 January 2010 13:48 UTC www.nal.usda.gov [Source type: Academic]

In the experiment, the snails were infected by their sympatric parasites, allopatric parasites and mixed sources of parasites. .The results suggest that the parasites were more highly effective in infecting their sympatric snails than their allopatric snails.^ In its award-winning documentary, The Body Snatchers , National Geographic magazine reported: "In fact, parasites have killed more humans than all the wars in history."

^ I have learned many more things than I knew before about parasitic life, and how they are heavily affecting human life.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ Parasite Deworming Your Horse - Four Common Parasites There are more than a hundred different internal parasites that can infect horses, donkeys, and mules.

.Though the allopatric snails were still infected by the parasites, the infectivity was much less when compared to the sympatric snails.^ Even though you are careful to drink only bottled water, if you order a drink with ice cubes made from the local water you could be infected with the Giardia parasite.

^ Sadly though, even with a much more educated public, I still hear clients tell me that a doctor or nurse has advised them to get rid of their cat during pregnancy.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ Pets Worms and Parasites: natural prevention and treatments An animal with a healthy immune system will be less likely to become infected with dog worms, including heartworm .
  • Worms and Parasites in humans and animals: natural herbal treatments 31 January 2010 13:48 UTC www.shirleys-wellness-cafe.com [Source type: FILTERED WITH BAYES]

.Hence, the parasites were found to have adapted to infecting local populations of snails.^ All the parasites found in wild boars except Gastrodiscoides hominis and Gnathostoma hispidum commonly infect the domestic pig(Soulsby, 1982).

^ Nearly one-third of the entire human population has been exposed to this nasty parasite that can sometimes infect the brain.

^ Ascaris Lumbricoides , a large roundworm, is the most common nematode parasite found in humans, infecting an estimated 1.47 billion individuals world-wide!

[8]

Transmission

Life cycle of Entamoeba histolytica, an anaerobic parasitic protozoan.
.Parasites inhabit living organisms and therefore face problems that free-living organisms do not.^ Therefore, the parasite is free to impose his own World Order, which has no organic relationship to the universe or to form.
  • The World Order a Study in the Hegemony of Parasitism 3 February 2010 17:22 UTC www.scribd.com [Source type: FILTERED WITH BAYES]

^ A human parasite is an organism or animal which lives inside the host human and survives and thrives by either eating the food ingested by the host, or by eating body cells and tissues of the host.

^ According to Brumpt (1913), parasites are all living beings, plants or animals, that during at least part of their lives depend upon another organism.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.Hosts, the only habitats in which parasites can survive, actively try to avoid, repel, and destroy parasites.^ In fact, the host is merely trying to survive by throwing off the parasite.
  • The World Order a Study in the Hegemony of Parasitism 3 February 2010 17:22 UTC www.scribd.com [Source type: FILTERED WITH BAYES]

^ We normally define parasites as orgamisms which cannot survive without their host and have special modifications to their body or their life cycle for this association.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ A human parasite is an organism or animal which lives inside the host human and survives and thrives by either eating the food ingested by the host, or by eating body cells and tissues of the host.

.Parasites employ numerous strategies for getting from one host to another, a process sometimes referred to as parasite transmission or colonization.^ Another law of nature is that the parasite, not only by sucking off the life sustenance of the host, but also by altering its life cycle, will inevitably kill the host.
  • The World Order a Study in the Hegemony of Parasitism 3 February 2010 17:22 UTC www.scribd.com [Source type: FILTERED WITH BAYES]

^ Many significant remnants in the genome of parasites and hosts are left during the co-evolution process of a host-parasite-environment system.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ In eurixene (eclectic) parasites, if virulence and transmission are linked characters, virulence may be considered as a fitness trait even if transmission requires the killing of the infected host.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.Some endoparasites infect their host by penetrating its external surface, while others must be ingested.^ The flood's toxin must need a very highly evolved nervous system to operate (in other words it needs a highly cognitive, sentient host) 5.
  • Halo Story Page | Story Elements | The Flood 17 January 2010 8:39 UTC halostory.bungie.org [Source type: Original source]

^ The trypanosomes must evade host defences that vary from arthropods or other invertebrate vectors to the bloodstream or the intracellular habitat of vertebrate hosts.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Under some circumstances, these malformations may enhance parasite transmission by rendering infected amphibian hosts more susceptible to definitive host predators.
  • Information Resources on Amphibians. Parasites: Animal Welfare Information Center 31 January 2010 13:48 UTC www.nal.usda.gov [Source type: Academic]

.Once inside the host, adult endoparasites need to shed offspring into the external environment in order to infect other hosts.^ When they enter the favorable environment of the mammalian or human body, the cysts transform into the parasitic trophozoite form of the protozoa and infect the body of the host.

^ The model of Koella and Doebeli [34] instead assumes that a small proportion of hosts are infected at the beginning of each cohort due to vertical transmission to offspring.
  • PLoS ONE: The Population Dynamical Implications of Male-Biased Parasitism in Different Mating Systems 3 February 2010 17:22 UTC www.plosone.org [Source type: Academic]

^ The flood's toxin must need a very highly evolved nervous system to operate (in other words it needs a highly cognitive, sentient host) 5.
  • Halo Story Page | Story Elements | The Flood 17 January 2010 8:39 UTC halostory.bungie.org [Source type: Original source]

Many adult endoparasites reside in the host’s gastrointestinal tract, where offspring can be shed along with host excreta. .Adult stages of tapeworms, thorny-headed worms and most flukes use this method.^ The term is used to group certain parasites together and includes the Nematodes, which are long, cylindrical worms, tapeworms, and flukes.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ Threats to Endangered Species: Brown-headed cowbird parasitism is one of the variables used in a scoring method to determined species prioritization for songbird conservation [ 28 ].
  • Molothrus ater 3 February 2010 17:22 UTC www.fs.fed.us [Source type: Academic]

.Among protozoan endoparasites, such as the malarial parasites and trypanosomes, infective stages in the host’s blood are transported to new hosts by biting-insects, or vectors.^ An external parasite is an insect that lives off the blood supply of the host.

^ It does not discuss the biting and blood-sucking parasites like mosquitos, horseflies, leeches and vampire bats which temporarily feed on a human host from outside, or those insect vampires like ticks, fleas, lice and bedbugs which attach themselves to the outer skin.

^ William W. Cort's School of Hygiene at Johns Hopkins supplied the developing network with many new students who continued to work on host parasite interactions.
  • Development of parasite immmunology 3 February 2010 17:22 UTC www.priory.com [Source type: Academic]

.Larval stages of endoparasites often infect sites in the host other than the blood or gastrointestinal tract.^ Parasite-Induced Change in Host Behavior: Intermediate stages will induce qualitative changes in the intermediate host such that the infected intermediate host is more likely to be captured by a predator which is the definitive host.
  • PARASITES 31 January 2010 13:48 UTC www.cbu.edu [Source type: Academic]
  • PARASITES 18 September 2009 9:27 UTC www.cbu.edu [Source type: Academic]

^ Often brutal authoritarian intriguers hate each other more than they are hated by libertarians.
  • Res_Opp_ideol-5-Parasitism 3 February 2010 17:22 UTC www.amfirstbooks.com [Source type: Original source]

.In many such cases, larval endoparasites require their host to be consumed by the next host in the parasite’s life cycle in order to survive and reproduce.^ We normally define parasites as orgamisms which cannot survive without their host and have special modifications to their body or their life cycle for this association.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ Another law of nature is that the parasite, not only by sucking off the life sustenance of the host, but also by altering its life cycle, will inevitably kill the host.
  • The World Order a Study in the Hegemony of Parasitism 3 February 2010 17:22 UTC www.scribd.com [Source type: FILTERED WITH BAYES]

^ I have learned many more things than I knew before about parasitic life, and how they are heavily affecting human life.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

.Alternatively, larval endoparasites may shed free-living transmission stages that migrate through the host’s tissue into the external environment, where they actively search for or await ingestion by other hosts.^ They cannot live and reproduce free in the environment.
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

^ Endoparasites live in the host’s interior (They may be intra- or extracellular).
  • Ecology, epidemiology, and evolution of parasitism in Daphnia by Dieter Ebert 3 February 2010 17:22 UTC www.evolution.unibas.ch [Source type: Academic]

^ When they are not on a host we call them 'free-living.'
  • Dog Parasites: Types, Transmission & Life Cycles 31 January 2010 13:48 UTC www.peteducation.com [Source type: FILTERED WITH BAYES]

.The foregoing strategies are used, variously, by larval stages of tapeworms, thorny-headed worms, flukes and parasitic roundworms.^ Typical medical lab tests for the presence of tapeworms and other flukes and worms usually involve examining stool samples to see if the adult parasites or their tiny eggs are present, but such tests do not detect the presence of Taenia solium larval cysts ( cysticerci ) hidden inside an organ or tissue.

^ Most nematode species are not parasitic, but some common types of parasitic intestinal worm are the pinworm, whipworm, hookworm, and roundworm.

^ The Radiolab podcast spent an episode examining parasites, and attempted to determine whether they are “evil or awesome,” by telling stories of the various lives and uses of parasites.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

.Some ectoparasites, such as monogenean worms, rely on direct contact between hosts.^ Some times the contact between mush and new sill is gradational, but if the sill is 90% solidified it may be quite abrupt.
  • Continental Flood Basalts 17 January 2010 8:39 UTC www.geokem.com [Source type: FILTERED WITH BAYES]

^ Pigs may also be infected, so contact with pig manure containing the worm eggs, or vegetables grown in contaminated pig manure, can transmit the Ascaris eggs to the mouth of a new human host.

^ Some species which infect animals such as dogs and cats, C. canis and C. felis , can also infect humans, and are transmitted by contact with dog or cat feces.

.Ectoparasitic arthropods may rely on host-host contact (e.g.^ Pigs may also be infected, so contact with pig manure containing the worm eggs, or vegetables grown in contaminated pig manure, can transmit the Ascaris eggs to the mouth of a new human host.

many .lice), shed eggs that survive off the host (e.g.^ Baylisascaris procyonis does not harm the raccoon host, which may continue to shed millions of roundworm eggs in its feces every day.

^ In fact, the host is merely trying to survive by throwing off the parasite.
  • The World Order a Study in the Hegemony of Parasitism 3 February 2010 17:22 UTC www.scribd.com [Source type: FILTERED WITH BAYES]

fleas), or wait in the external environment for an encounter with a host (e.g. ticks). .Some aquatic leeches locate hosts by sensing movement and only attach when certain temperature and chemical cues are present.^ Scaleworms are known for being commensals; some will only attach to a single species while others can live on a variety of other creatures.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ One which flows only at certain times of the year when it receives water from springs or from some surface source such as melting snow in mountainous areas.
  • Science in Your Watershed - General Introduction and Hydrologic Definitions 17 January 2010 8:39 UTC water.usgs.gov [Source type: Academic]

.Some parasites modify host behaviour to make transmission to other hosts more likely.^ Modification of intermediate host behaviour by parasites.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ HUMAN PARASITES Myself and a handful of others, like Dr. Hulda Clark, have spent years trying to bring the parasite issue to the forefront of preventative & curative medicine.
  • A Herbal Healer Academy - Parasites 31 January 2010 13:48 UTC www.herbalhealer.com [Source type: FILTERED WITH BAYES]

^ Evolutionarily speaking, this makes more sense, as the grazing times of cattle and sheep (also an occasional host) dictate a greater amount of grazing during daylight hours.
  • Damn Interesting • A Fluke of Nature 31 January 2010 13:48 UTC www.damninteresting.com [Source type: FILTERED WITH BAYES]

For example, in California salt marshes the fluke Euhaplorchis californiensis reduces the ability of its killifish host to avoid predators.[9] .This parasite matures in egrets, which are more likely to feed on infected killifish than on uninfected fish.^ In its award-winning documentary, The Body Snatchers , National Geographic magazine reported: "In fact, parasites have killed more humans than all the wars in history."

^ I have learned many more things than I knew before about parasitic life, and how they are heavily affecting human life.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ Although no-one carried out any research in this area, I personally believe that because of the parasitism dies more people than because of any other illness.
  • Parasitism - the philosphy of immorality, stagnation, aggression and unhappiness (in English) 3 February 2010 17:22 UTC www.anzwers.org [Source type: Original source]

.Another example is the protozoan Toxoplasma gondii, a parasite that matures in cats but can be carried by many other mammals.^ An infection by the Toxoplasma gondii protozoan parasite is known as Toxoplasmosis .

^ Facts: 1.Toxoplasma gondii affects most animals (most notably sheep, cats, and humans), but even insects, fish, and earthworms may be carriers.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ Lastly, the podcast talks about toxoplasma which is another type of parasite.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

.Uninfected rats avoid cat odours, but rats infected with T. gondii are drawn to this scent, a change which may increase transmission to feline hosts.^ Preferred definitive host: Rats, mice, hamsters, dogs and cats .
  • PARASITES 31 January 2010 13:48 UTC www.cbu.edu [Source type: Academic]
  • PARASITES 18 September 2009 9:27 UTC www.cbu.edu [Source type: Academic]

^ If a rat becomes infected with it, the parasite “rewires” the rat’s brain to be attracted to cats.
  • WNYC - Radiolab » Parasites 31 January 2010 13:48 UTC blogs.wnyc.org [Source type: General]

^ Yet on the other hand, both parasite and host will be exterminated if this increase of virulence occurs at the expense of the host before the parasite reaches transmission.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

[10]

Roles in ecosystems

.Modifying the behaviour of infected hosts to make transmission to other hosts more likely is one way parasites can affect the structure of ecosystems.^ Modification of intermediate host behaviour by parasites.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ It is not likely that other species will be affected.
  • Dog Parasites 31 January 2010 13:48 UTC www.vetinfo.com [Source type: FILTERED WITH BAYES]

^ Internal parasites can also make a pet more susceptible to other diseases.
  • Internal Parasites (Worms) 31 January 2010 13:48 UTC www.lbah.com [Source type: FILTERED WITH BAYES]

.For example, in the case of Euhaplorchis californiensis (discussed above) it is plausible that the abundance of local predator and prey species would be different if this parasite were absent from the system.^ Host and microhabitat specificity, for example, may be affected by the age of host and parasite, presence or absence of other competitive parasite species, and the numbers of parasite individuals present.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Submitted to natural selection and/or the inherent properties of a system, the parasite-host-environment system reacts to changes in each subsystem with different responses, according to the features of the stimulus.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ For example, I have read that in certain tropical rain forest jungles, parasites comprise approximately half the animal species.
  • Res_Opp_ideol-5-Parasitism 3 February 2010 17:22 UTC www.amfirstbooks.com [Source type: Original source]

.Although parasites are often omitted in depictions of food webs, they usually occupy the top position.^ The shepherd and his six children gathered all the food and sheep they could and took them to the top of the very tall mountain Ancasmarca.
  • Flood Stories from Around the World 17 January 2010 8:39 UTC www.talkorigins.org [Source type: Original source]

^ I don't think they fit your specifications, although there are interesting thoughts that plant plastids are in fact obligate parasite or commensal protozoa in plants.
  • The Sea Slug Forum - Symbiosis, commensalism, mutualism and parasitism 3 February 2010 17:22 UTC www.seaslugforum.net [Source type: General]

^ As one can gether from these web pages, our planet is just secretly occupied by these "evil parasites" from space.
  • Parasitism - the philosphy of immorality, stagnation, aggression and unhappiness (in English) 3 February 2010 17:22 UTC www.anzwers.org [Source type: Original source]

.Parasites can function like keystone species, reducing the dominance of superior competitors and allowing competing species to co-exist.^ For example, does brood parasitism typically originate with the parasitism of closely related hosts species that are more likely to provide appropriate parental care for parasitic chicks?
  • Molecular Genetic Perspectives on Avian Brood Parasitism -- Sorenson and Payne 42 (2): 388 -- Integrative and Comparative Biology 3 February 2010 17:22 UTC icb.oxfordjournals.org [Source type: Academic]

^ Life emerged as a consequence of parasitism at the molecular level, and intracellular parasitism created evolutive events that allowed species to diversify.
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

^ Parasites are found in every organism of all existing species on earth (Poulin & Morand 2000).
  • Mem�rias do Instituto Oswaldo Cruz - Parasitism, the diversity of life, and paleoparasitology 3 February 2010 17:22 UTC www.scielo.br [Source type: Academic]

.Many parasites require multiple hosts of different species to complete their life cycles and rely on predator-prey or other stable ecological interactions to get from one host to another.^ Like many another arthropod parasite, it causes its hosts to itch.
  • Parasites and Parasitology – FREE Parasites and Parasitology information | Encyclopedia.com: Find Parasites and Parasitology research 18 September 2009 9:27 UTC www.encyclopedia.com [Source type: FILTERED WITH BAYES]

^ Parasite survives predation on its host.
  • PLoS ONE: Parasitoid Increases Survival of Its Pupae by Inducing Hosts to Fight Predators 3 February 2010 17:22 UTC www.plosone.org [Source type: Academic]

^ Each species has different grazing behavior that complements one another.
  • Sheep 201: Internal parasite (worm) control 31 January 2010 13:48 UTC www.sheep101.info [Source type: FILTERED WITH BAYES]

.In this sense, the parasites in an ecosystem reflect the "health" of that system.^ Now, in perfect health and with a strong immune system , I don't have to worry about parasites of infections anymore.
  • Worms and Parasites in humans and animals: natural herbal treatments 31 January 2010 13:48 UTC www.shirleys-wellness-cafe.com [Source type: FILTERED WITH BAYES]

^ When I was a child I was in poor health and my weak immune system could not protect me against all sorts of infections and parasites.
  • Worms and Parasites in humans and animals: natural herbal treatments 31 January 2010 13:48 UTC www.shirleys-wellness-cafe.com [Source type: FILTERED WITH BAYES]

See also

References

  1. ^ H. Charles & J. Godfray (2004). "Parasitoids". Current Biology Magazine 14 (12): R456. doi:10.1016/j.cub.2004.06.004.  [1]
  2. ^ "Bullies of the Bird World - National Wildlife Magazine." Aug/Sep 1997, Vol. 35 No. 5[2]
  3. ^ a b Price, P.W. 1980. Evolutionary Biology of Parasites. Princeton University Press, Princeton
  4. ^ http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0007288;jsessionid=46F0A1EFB5E7F840BE2194BA7F0AEC02
  5. ^ Rook, G.A.W. (2007). "The hygiene hypothesis and the increasing prevalence of chronic inflammatory disorders". Transactions of the Royal Society of Tropical Medicine and Hygiene 101: 1072–4. doi:10.1016/j.trstmh.2007.05.014. 
  6. ^ SwitzerWM, Salemi M, Shanmugam V, Gao F, Cong ME, Kuiken C, Bhullar V, Beer BE, Vallet D, Gautier-Hion A, Tooze Z, Villinger F, Holmes EC, Heneine W. Ancient co-speciation of simian foamy viruses and primates. Nature. 2005 Mar 17; 434(7031):376-80.
  7. ^ Rózsa L, Reiczigel J, Majoros G 2000. Quantifying parasites in samples of hosts. Journal of Parasitology, 86, 228-232.
  8. ^ a b Lively, Curtis M. and Dybdahl, Mark F. "Parasite adaptation to locally common host genotypes." Nature. Vol. 405. 8 June 2000.
  9. ^ Lafferty, K. D. and A. K. Morris. 1996. Altered behavior of parasitized killifish increases susceptibility to predation by bird final hosts. Ecology 77:
  10. ^ Berdoy M, Webster JP, Macdonald DW (2000). "Fatal attraction in rats infected with Toxoplasma gondii". Proc. Biol. Sci. 267 (1452): 1591–4. doi:10.1098/rspb.2000.1182. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=. 

Further reading

  • Zimmer, Carl (2001). Parasite Rex. Free Press. pp. 320. ISBN 074320011X. 
  • Combes, Claude (2005). The Art of Being a Parasite. .The University of Chicago Press.^ The Gilgamesh Epic and Old Testament Parallels , University of Chicago Press, 1949.
    • Flood Stories from Around the World 17 January 2010 8:39 UTC www.talkorigins.org [Source type: Original source]

    pp. 280. ISBN 0226114384.
     
  • Desowitz, Robert (1998). Who Gave Pinta to the Santa Maria?. Harvest Books. pp. 264. ISBN 0156005859. 

External links


1911 encyclopedia

Up to date as of January 14, 2010
(Redirected to Database error article)

From LoveToKnow 1911

(There is currently no text in this page)


Simple English

Parasitism is a form of symbiosis. It means that a parasite is any organism or living thing that benefits from another creature's harm. In other words, the parasites harm the host organism while the parasite benefits. A parasitic relationship is the opposite of a mutualistic relationship.[1] Examples of parasites in humans include tapeworms and leeches. World-wide, the most serious cause of human death by a parasite is malaria. A definition:

  • A parasite is an organism living in or on another living organism, obtaining from it part or all of its food. It usually shows some degree of adaptive modification, and causes some degree of damage to its host.[2]

Contents

Biological context

When the above definition is applied, many organisms which eat plants can be seen as parasites, because they feed largely or wholly on one individual plant. Examples would include many herbivorous insects: the Homoptera (leafhoppers, froghoppers, aphids, scale insects and whiteflies). The larvae of Lepidoptera usually feed and mature on a single individual of the host plant species, and what they eat accounts for most of the food for their complete life span. Moreover, caterpillars can and often do serious damage to the host's foliage. Other orders also have many parasitic herbivores: Thysanoptera (thrips). Hemiptera (true bugs), Coleoptera (beetles), Diptera (flies). s parasitising a harvestman]]

Parasites of larger animals account for much research done for veterinarian and medical purposes. These parasites include viruses, bacteria, protozoa, flatworms (flukes and tapeworms), nematodes (roundworms), arthropods (crustacea, insects, mites). Parasitic wasps and flies are of great interest to the entomologist, and may be used in biological control.

On the other hand, many blood-sucking insects (such as mosquitos) have only brief contact with a host, and so perhaps should not be regarded as parasites.[3]

A huge number of species are parasitic. A survey of the feeding habits of British insects showed that about 35% were parasites on plants, and slightly more were parasites on animals.[4] That means that nearly 71% of insects in Britain are parasitic. Since British insects are better known than those elsewhere (because of the length of time they have been studied), this means that the majority of insect species throughout the world are parasitic. Also, there are several other invertebrate phyla which are wholly or largely parasitic. Flatworms and roundworms are found in virtually every wild species of vertebrate. Protozoan parasites are also ubiquitous. Hence parasitism is almost certainly the most common feeding method on Earth.[3]

Terminology of parasitism

  • Ectoparasites live on the outside of a plant or animal.
  • Endoparasites live inside a plant or animal. Intracellular parasites live inside cells; Intercellular parasites live in the spaces between cells.
  • Parasitoids are organisms whose larval development takes place within another organism's body, resulting in the death of the host. There are twelve Superfamilies of wasps which are entirely or mainly parasitoid, such as the ichneumon wasps, whose species number over 80,000. The interaction between the parasitoid and the host is fundamentally different from true parasites and their host, and shares some characteristics with predation.
  • A vector is a third party that carries the parasite to the host. Thus, with malaria, the mosquito is the vector, the sporozoite protozoan is the parasite, and the mammal is the host.
  • An epiparasite is one that feeds on another parasite.
  • Kleptoparasites steal food from other species.
  • Brood parasites (such as the Cuckoo) induce other species to raise their young. The Cowbird is another brood parasite.
  • Social parasites take advantage of interactions between members of social organisms such as ants or termites.

Ecology

Dispersal and reproduction

Parasites are adapted to small, separated habitats. For a parasite, each host is an island surrounded by a hostile environment.[5] For a small organism, the distances between hosts, or groups of hosts, is a hazard. Adaptations to bridge this hazard are:

  • Mass production of spores or eggs.
  • Dispersal of fertile females.
  • Dispersal by attaching to a larger organism (many ectoparasites).
  • Extreme longevity of resting stages (spores or cysts). For example, plant parasitic nematodes may remain quiescent for 23 years.[6]
  • Parthenogenesis, and inbreeding among offspring of a single female, are common in parasites.

So parasites exist in small, genetically similar groups with little flow of genes between them. In consequence, they have adaptations to solve their problems of dispersal and reproduction.[3]

Parasites are highly specialised

Parasites face an environment which varies in time and space. Consequently, both local (geographic) races and polymorphism occur. Both may occur in the same species. Parasites are very specialised feeders: many species have only one host; and only a minority use more than two host species.[3]

Complex life cycles

Many parasites have complex life-cycles. Tremadodes, the flukes, are a parasitic class of flatworms (Platyhelminths), with over 20,000 species. Most of them infect molluscs in the first part of the life-cycle, and vertebrates in the second part. The biology of scrub typhus is even more complex. It involves these factors:[7]

1. The pathogen bacterium Rickettsia.
2. Chiggers, which are ectoparasitic mites.
3. Small mammals, especially rats.
4. Scrubby vegetation with moist conditions
5. Humans passing through patches where the above are present.

The occurrence of all these factors together would be limited in space, and brief in time. This is typical of the ecology of parasitic infections.

Evolution

Rapid speciation

Both evolutionary rates and speciation rates can be high. Sibling species are very common in the bug Erythroneura, in which about 150 transfers from one host to another has resulted in about 500 species in the genus.[8]

The clearest evidence comes from the large size of many parasitic families.

"Even though some parasitic taxa evolved much later than predatory taxa, families of parasites on plants are on average almost eight times larger than those of predators, and families of parasites on animals are over ten times larger." Price p26.[3]

Sometimes there is good evidence of the speed of speciation. For example, five or more species of the moth Hedylepta must have evolved within 1000 years in Hawaii, because they are specific to banana, which was only introduced then.[9]

Adaptive radiation

Adaptive radiation in parasites is extensive. Its development in each taxon (group) depends on:

The diversity of the hosts. How many species there are in the group being parastised, and how different they are from each other.
The size of the host target: body size, population, geographical distribution.
The evolutionary time available for colonisation of hosts.
The selective pressure for evolutionary modification.

Diversity of hosts is a big factor. If many related species of host are available, then many related species of parasite will evolve. Mites on Lepidoptera families or fleas on mammals and birds are good examples. Eichler's rule goes as follows:

"When a large group of hosts consisting of a wide variety of species is compared with an equivalent group consisting of few representatives, the larger group has the greater diversity of parasitic fauna".[10]

The two British oaks support some 439 specieas of parasite directly, and indirectly many hundred more which parasitise these parasites. "It would certainly be an underestimate to say that the two British species of oak are the primary products for a thousand species of parasite".[3] p28 Obviously, the large size of these trees is a factor in the number of parasite species. In general, this holds whether the host is a plant or an animal. A larger bird will harbour more species of ectoparasite than a small bird.

More time, more species

One of the reasons large trees have so many parasites is that they may have lived a long time in a particular area compared with other types of plant. They have had longer to accumulate parasites.

Parasites can be most useful in sorting out the phylogenetic relationships of their hosts. Sibling host species have been discovered when their parasites diverged. Common ancestors of present-day parasites were themselves parasites of the common ancestors of present-day hosts.

Selection for co-evolution

As the host evolves defences, so the parasite evolves to cope with this. Compare two families of host plants, the Umbellifers (fennel, cumin, parsley, hemlock) and the Graminae (grasses). The umbellifers have many aromatic species, and are chemically diverse and pharmaceutically interesting. Their resins and oils are defences againt herbivory and parasitism. On the other hand, grasses have one big defence to herbivores: their stony inclusions in their cells wear down the teeth of herbivorous mammals, but they have few chemical defences. Both families are attacked by leaf-miner flies. There are four times as many grass species as there are umbellifers, but there are twice as many leaf-miner species on the umbellifers.

"This is apparently because the chemical diversity of potential hosts within the Umbelliferae has forced specialisation of the parasites. Eighty-two percent of the species of leaf-miner attack only one genus each".[3]

Sympatric speciation

This is speciation which does not require geographical isolation. Ernst Mayr, the chief exponent of geographical speciation, admitted that host races of phytophagous animals "constitute the only known case indicating the possible occurrence of incipient sympatric speciation".[11]

References

  1. A relationship between two different organisms where both benefit.
  2. Webster's Third International Dictionary, slightly adapted; similar is the Oxford English Dictionary.
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Price P.W. 1980. Evolutionary biology of parasites. Princeton N.J.
  4. Kloet G.S. and Hincks W.D. 1945. A check list of British insects. Stockport.
  5. Williams G.C. 1975. Sex and evolution. Princeton.
  6. Cooper A.F. Jr and Van Gundy S.D. 1971. Senescence, quiescence and cryptobiosis. In Zuckerman et al (eds) Plant parasitic nematodes. Academic Press N.Y.
  7. Traub R. and Wisseman C.L. Jr 1974. The ecology of chigger-bourne rikettsiosis (scrub typhus). J. Medical Entomology 11, 237–303.
  8. Ross H.H. 1962. A synthesis of evolutionary theory. Prentice-Hall N.J.
  9. Zimmerman E.C. 1960. Possible evidence of rapid evolution in Hawaiian moths. Evolution 14, 137–138.
  10. Noble E.R. and Noble G.A. 1976. Parasitology: the biology of animal parasites. Lea & Febiger, Philadelphia. p504
  11. Mayr, Ernst 1963. Animal species and evolution. Harvard, Cambridge Mass. p460


Citable sentences

Up to date as of December 20, 2010

Here are sentences from other pages on Parasitism, which are similar to those in the above article.








Got something to say? Make a comment.
Your name
Your email address
Message