Humans have learnt a lot about themselves from lice. Genetic studies of the human pubic louse, Pthirus pubis, show that it is very closely related to the gorilla louse, Pthirus gorillae. Gorillas and humans shared the same lice for two million years after they had themselves diverged, so we can conclude that our hominid ancestors used to sleep either with gorillas or in their abandoned nests.
Genetic analysis of head lice tells us that we split from chimpanzees 5.5 million years ago, and that we caught a second species from the heads of our now extinct cousins, Homo erectus, three million years later. Body lice (P. humanus humanus) live only in clothing and evolved from head lice about 70,000 years ago, thus telling us when humans first started getting dressed.
The ‘nits’ that children catch are the eggs of the lice, which they stick to the base of the hair using special cement. It’s so strong that some females end up sticking themselves to a strand of hair and starving to death. Lice lay six eggs a day, and the optimum population (from their point of view) is about 100 lice per head.
I used to always be putting my hat on children being photographed and then getting home and discovering I was riddled with lice.
Analysis of the remains of Napoleon’s soldiers who died in the retreat from Moscow confirms that lice killed more men than the Russians did.
Lice are very small, wingless insects related to aphids and cicadas. They live as parasites in the fur or feathers of mammals and birds, feeding on blood, dead skin or feather parts. Almost all species that carry lice support one or two different lice species in different parts of their body. Notable exceptions are bats, platypuses and echidnas, which are lice-free.
The major downside to being a louse is you that can only survive for a day or two if you are separated from your host. This is why, since the passenger pigeon had became extinct in 1914, it was presumed that the passenger pigeon louse - described for the first time in 1937 - was also extinct. It was therefore named Columbicola extinctus. Only in 1999 was it rediscovered, happily living on Band-tailed Pigeons. It now has the odd distinction of having its name mean 'extinct', despite the fact that it still exists.
The attempt to breed Californian condors in captivity inadvertently destroyed the condor-chewing louse (Colpocephalum californici) when the last few remaining birds were fumigated.
It isn’t true that head lice prefer clean hair. They’re indifferent to cleanliness as long as there’s a suitable blood supply.
Each species of whale has its own species of louse, which makes these lice as endangered as their hosts.
Only one species of louse is officially classified by the International Union for Conservation of Nature as ‘critically endangered’: Haematopinus oliveri, or the pygmy hog sucking louse, which lives on the dwindling pygmy hog population of northern India. The louse depends for its existence on a host that is itself endangered, so is described as ‘co-endangered’.
As few as 150 pygmy hogs (Porcula salvanius) survive in the wild, faced as they are with hunting, pythons, habitat destruction and the aggressive incursions of wild boars into their territory. Pygmy hogs are not much bigger than a terrier when fully grown and are important because recent genetic evidence has shown they are the only species in a distinct genus of the pig family: Porcula. It had previously been assumed that they were a member of the main branch of the pig family: Sus. They live on roots, insects, small animals and reptiles. To shelter from the sun, they build high dome-like nests that they line with vegetation.
Human body lice can only live in clothing.
‘All that we caught, we left behind, and carry away all that we did not catch. What am I talking about?’ The answer to this riddle is ‘lice’ and - according to an anonymous account of his life, Of the Origin of Homer and Hesiod, and of Their Contest – it was the riddle that killed Homer. The lice that you catch, you throw away – the ones you don’t catch stay on your body.
The oracle at Delphi told Homer he would die on the island of Ios, and that he should ‘beware of the riddles of young children’. Later, travelling round the Greek islands as a minstrel, Homer visited Ios where he encountered a group of fisher-boys and asked them what they had caught. They gave him their riddle, he remembered the oracle and, realising his fate, he composed his own epitaph. He then slipped and died.
Woodlice have 14 legs.
Waxing and shaving of pubic hair is killing off the population of crab lice.
The louse Columbicola extinctus is not extinct.
Adult lice look like tiny crabs, hence their nickname. They have powerful pincers on their front legs, which they use to anchor themselves close to their host’s skin, by grabbing hair or feather barbs. The shape of some bird lice has evolved to fit exactly in between the barbs so they can't be removed by preening (which is why birds have dust baths).
Lice can't jump
A nab-nanny is on old word for a louse. The Norfolk phrase refers to the fact that nannies would have to catch the bugs.
Biddies is one of the traditional names for lice - from Durham. They're also known as bobos (in Orkney).
No rats are free from fleas; 67% have mites and 38% have lice.