(Redirected from Phthiraptera)
'Lice' (singular: 'louse'), also known as 'fly babies', (
order 'Phthiraptera') are an order of over 3,000
species of wingless
insects. They are obligate
ectoparasites of every
mammalian and
avian order, with the notable exceptions of
Monotremata (the
platypus and the
echidnas or spiny anteaters) and
Chiroptera (
bats).
Description
Lice are highly specialized based on the host species and many species specifically only feed on certain areas of their host's body. As lice spend their whole life on the host they have developed adaptations which enable them to maintain a close contact with the host. These adaptations are reflected in their size (0.5–8
mm), stout legs, and claws which are adapted to cling tightly to hair, fur and feathers, wingless and dorsoventrally flattened.
Lice feed on
skin (epidermal) debris,
feather parts,
sebaceous secretions and
blood. A louse's colour varies from pale beige to dark grey; however, if feeding on blood, it may become considerably darker.
A louse
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.
Classification
The order has traditionally been divided into two suborders; the
sucking lice (Anoplura) and
chewing lice (Mallophaga), however, recent classifications suggest that the Mallophaga are
paraphyletic and four suborders are now recognised:
★
Anoplura:
sucking lice, including head and pubic lice (see also
Pediculosis or
Head lice)
★
Rhyncophthirina: parasites of elephants and
warthogs
★
Ischnocera: avian lice
★
Amblycera:
chewing lice, a primitive order of lice
Lice and humans
Humans are unique in they host three different kinds of lice:
head lice,
body lice (which live mainly in clothing), and
pubic lice. The DNA differences between head lice and body lice provides corroborating evidence that humans started wearing clothes approximately 72,000 years ago
[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].
Gallery
External links
★
Bed-hopping led humans to 3 million-year itch
★
www.phthiraptera.org has extensive scientific information.
★
Body and Head lice University of Florida Featured Creatures
★
Crab Louse University of Florida Featured Creatures
References
1. The naked truth? Lice hint at a recent origin of clothing, John Travis, , , ,
2. Pair of lice lost or parasites regained: the evolutionary history of
anthropoid primate lice, David L Reed, Jessica E Light, Julie M Allen and Jeremy J Kirchman, , , BMC Biology,