Some more ridiculous but true facts about animals from the book Bats Sing, Mice Giggle:
The tiny black-capped chickadee, a bird widespead in the USA has a warning song: it adds ‘dees’ to its normal cry, and the more it adds, – up to 20 – the more danger it is warning of, not just to its own species but also to the nuthatch and titmouse that it is often found in company with.
When the Australian magpie sees a predator it has two responses, relating to different sides of its brain. It can fix on the predator with its left eye whilst fleeing, this links to the right hemisphere, dealing with novel and threatening sights. Or it can move closer using its right eye which links to the right hemisphere for detailed analysis.
Chameleons change colour more dramatically and precisely for birds rather than snakes as snakes have poor colour perception, so save themselves effort.
Chameleons are also brilliant at regenerating body parts to the extent that you can take out their brains, put them in a blender, then put them back and they will recover. Eaugh!
Squirrels are usually pretty smart, but when grey squirrels run up grey tree trunks to become camouflaged, albinos do the same, so are visible to predators.
Ground squirrels usually signal danger by waving their tails, but one variety has a tail that can become hot, and is waved menacingly at rattlesnakes that are sensitive to infrared, so scares them away.
Ground squirrels also chew snakeskin, and spear themselves with the saliva so making themselves and their homes smell of snake, so repelling predators. Rats often make themselves smell of weasel and hedgehogs smell of toads.
There are also some great stories about migrating birds, but I love the one about the timings of swallows. Those that roost in the abandoned church of San Juan Capistrano to the south west of Los Angeles always arrive on 19 March, St Joseph’s day, and depart on 23 October, San Juan Day. They circle a few times before they depart, as a way of saying goodbye.
I find these dates intriguing as they are totally unrelated to seasons or daily weather. Is there some historical significance in these days? Did the folk of San Juan feed them on their arrival and before their departure? Is this why they continue to stick to these dates, even in the absence of any apparent reason?