There is considerable argument to suggest that the Sucking Lice (Siphunculata) and the Biting Lice (Mallophaga) are part of a single order the 'Anopleura' and you may find that what I have treated as two separate orders here, are classified as two suborders under the common title of 'Anoplura' elsewhere. Unless you are a taxonomist or very seriously studying these insects it is not important to make a decision which form of classification you prefer.
The Mallophaga are described as wingless (Apterous), hemimetabolous (having a simple metamorphosis i.e. no pupa) ectoparsites (living on the outside of their hosts) of mostly birds but also of some mammals, there are about 2 800 species world wide. The range in size from 0.5 to 10 mm long dorsoventrally flattened with reduced compound eyes and no ocelli. The antennae are 3 to 5 segmented and capitate (with a knob on the end) and recessed into the head in the Amblycera but filiform (thin and linear) in the Ischnocera and may be modified as clasping organs in the male. Their mouthparts are designed for biting and they have no cerci, there is some suggestion that they may have evolved from the Psocoptera (Book and Bark Lice).
Most feed on fragments of hair and feathers though some such as Menocanthus spp feed on their hosts blood as well. Some have formed a symbiotic relationship with bacteria which live in special Mycetocytes in the insects fat reserves, these may help with the digestion of blood etc as individuals deprived of their bacteria die in a few days. They are often adapted to live on particular parts of their hosts bodies, on Pigeons for instance Colombicola colombae is found mainly on the remiges (flight feathers) of the wings while Goniocoles bidentatus tends tobe restricted to the feathers around the neck.
They can only survive for a maximum of three days after their host has died and may hitch a ride on a passing fly (phoresis) in the hope of reaching a new host, they may also use phoresis in order to spread to a new host even if the present one is still alive.
Females lay up to 100 eggs which are cemented to the hair or feathers of the host with a clear fast drying glue which is secreted onto the hair or feather by the female immediately before she lays the egg. The eggs take about 3 or 4 days to hatch and the nymphs go through 3 larval instars in about 20 days before they reach maturity.