Louse: Wikis

  
  
  
  

Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.

Did you know ...


More interesting facts on Louse

Include this on your site/blog:

Encyclopedia

From Wikipedia, the free encyclopedia

Phthiraptera
Light micrograph of Fahrenholzia pinnata
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Subclass: Pterygota
Infraclass: Neoptera
Order: Phthiraptera
Haeckel, 1896
Suborders

Anoplura
Rhyncophthirina
Ischnocera
Amblycera

Lice (singular: louse), also known as fly babies, is the common name for over 3000 species of wingless insects of the order Phthiraptera; three of which are classified as human disease agents. They are obligate ectoparasites of every avian and mammalian order except for Monotremes (the platypus and echidnas), bats, whales, dolphins, porpoises and pangolins.

Contents

Biology

Most lice are scavengers, feeding on skin and other debris found on the host's body, but some species feed on sebaceous secretions and blood. Most are found only on specific types of animal, and, in some cases, only to a particular part of the body; some animals are known to host up to fifteen different species, although one to three is typical for mammals, and two to six for birds. For example, in humans, different species of louse inhabit the scalp and pubic hair. Lice generally cannot survive for long if removed from their host.[1]

A louse's color varies from pale beige to dark gray; however, if feeding on blood, it may become considerably darker. Female lice are usually more common than the males, and some species are even known to be parthenogenetic. A louse's egg is commonly called a nit. Many lice attach their eggs to their host's hair with specialized saliva; the saliva/hair bond is very difficult to sever without specialized products. Lice inhabiting birds, however, may simply leave their eggs in parts of the body inaccessible to preening, such as the interior of feather shafts. Living lice eggs tend to be pale white. Dead lice eggs are more yellow.[1]

Lice are exopterygotes, being born as miniature versions of the adult, known as nymphs. The young moult three times before reaching the final adult form, which they usually reach within a month of hatching.[1]

Classification

World War II-era American poster, created to prevent the transmission of lice between servicemen.

The order has traditionally been divided into two suborders, the sucking lice (Anoplura) and the chewing lice (Mallophaga); however, recent classifications suggest that the Mallophaga are paraphyletic and four suborders are now recognised:

It has been suggested that the order is contained by the Troctomorpha suborder of Psocoptera.

Lice and humans

Humans host three different kinds of lice: head lice, body lice , and pubic lice. The DNA differences between head lice and body lice provide corroborating evidence that humans started losing body hair about 2,000,000 years ago.[2]

Recent DNA evidence suggests that pubic lice spread to humans approximately 2,000,000 years ago from gorillas.[3]

Adult and nymphal lice can survive on sheep-shearers' moccasins for up to 10 days, but microwaving the footwear for five minutes in a plastic bag will kill the lice.[4]

Lice infestations can be controlled with lice combs, and medicated shampoos or washes.

Gallery

See also

Notes

  1. ^ a b c Hoell, H.V., Doyen, J.T. & Purcell, A.H. (1998). Introduction to Insect Biology and Diversity, 2nd ed.. Oxford University Press. pp. 407–409. ISBN 0-19-510033-6. 
  2. ^ John Travis (2003-08-23) ( – Scholar search). The naked truth? Lice hint at a recent origin of clothing. 164. Science News. pp. 118. http://www.sciencenews.org/articles/20030823/fob7.asp. 
  3. ^ David L Reed, Jessica E Light, Julie M Allen and Jeremy J Kirchman (2007). [http://www.biomedcentral.com/1741-7007/5/7 "Pair of lice lost or parasites regained: the evolutionary history of anthropoid primate lice"]. BMC Biology 5: 7. doi:10.1186/1741-7007-5-7. http://www.biomedcentral.com/1741-7007/5/7. 
  4. ^ Sheep parasites Retrieved on 10 November 2008

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

Phthiraptera
File:Fahrenholzia
Fahrenholzia pinnata
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Subclass: Pterygota
Infraclass: Neoptera
Order: Phthiraptera
Haeckel, 1896

Lice (singular: louse), are wingless insects of the Order Phthiraptera. They are all external parasites, on every species of birds and most mammalian orders. They are not found on Monotremes (the platypus and the echidnas or spiny anteaters) and a few eutherian orders, namely the bats (Chiroptera), whales, dolphins and porpoises (Cetacea) and pangolins (Pholidota). There are more than 3,000 different species; three are classified as human lice.

Contents

Description

Lice spend their whole life on the host. For are adapted to keep close contact with the host. These adaptations are reflected in their size (0.5–8 mm), stout legs, and claws which are adapted to clinging tightly to hair, fur and feathers. They are also wingless and flattened.

Lice feed on skin (epidermal) debris, feather parts, sebaceous secretions and blood. A louse's color varies from pale beige to dark grey; however, if feeding on blood, it may become considerably darker.

A louse's egg is commonly called a nit. Lice attach their eggs to their host's hair with specialized saliva which results in a bond that is very difficult to separate without specialized products. Living lice eggs tend to be pale white. Dead lice eggs are more yellow. Lice are very annoying and are difficult to remove, but not impossible. The process is called nit-picking, and is often done with a close-toothed metal comb. For humans, anti-insect shampoos are available.

Classification

The order has traditionally been divided into two suborders; the sucking lice (Anoplura) and chewing lice (Mallophaga). Four suborders are now recognised:

  • Anoplura: sucking lice, including head and pubic lice
  • Rhyncophthirina: parasites of elephants and warthogs
  • Ischnocera: avian lice
  • Amblycera: chewing lice, a primitive order of lice
  • Amblycera: Jumping Lice have very strong hind legs and can jump a distance of three feet

It has been suggested that the order is contained by the Troctomorpha suborder of Psocoptera. What this means is that lice may have evolved from free-living species of that group.

Lice and humans

Humans are unique in that they host three different species of lice: head lice, body lice (which live mainly in clothing), and pubic lice. The DNA differences between head lice and body lice provide corroborating evidence that humans started wearing clothes at approximately 70,000 BCE.[1]

Recent DNA evidence suggests that pubic lice spread to the ancestors of humans approximately 3.3 million years ago from the ancestors of gorillas by sharing the same bed or other communal areas with them, and are more closely related to lice endemic to gorillas than to other lice species infesting humans.[2]

  1. John Travis (2003). "The naked truth? Lice hint at a recent origin of clothing". Science News. pp. 118. Archived from the original on 2008-09-30. http://findarticles.com/p/articles/mi_m1200/is_/ai_107897267. 
  2. David L Reed, Jessica E Light, Julie M Allen and Jeremy J Kirchman (2007). [Expression error: Unexpected < operator "Pair of lice lost or parasites regained: the evolutionary history of anthropoid primate lice"]. BMC Biology 5: 7. doi:10.1186/1741-7007-5-7. 

Gallery

Error creating thumbnail: sh: convert: command not found

Other pages

Other websites

The English Wiktionary has a dictionary definition (meanings of a word) for:

References

  1. John Travis (2003). "The naked truth? Lice hint at a recent origin of clothing". Science News. pp. 118. Archived from the original on 2008-09-30. http://findarticles.com/p/articles/mi_m1200/is_/ai_107897267. 
  2. David L Reed, Jessica E Light, Julie M Allen and Jeremy J Kirchman (2007). [Expression error: Unexpected < operator "Pair of lice lost or parasites regained: the evolutionary history of anthropoid primate lice"]. BMC Biology 5: 7. doi:10.1186/1741-7007-5-7. 







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