Infozoic is a blog of research, analysis and explanation on subjects like science, technology, history, and others.
They are said to have evolved as a group so as not to compete with the other large group of flying vertebrates: the birds, which largely dominate the daytime sky;
Being nocturnal, the smaller species also avoid being preyed upon by predatory birds such as eagles and hawks.
But it is also, and perhaps mainly because of their anatomy, that they must rest on the head. They couldn't take off and flap their wings off the ground like birds (yes they can, but they don't normally do it that way because it's a huge waste of energy and very uncomfortable and their wings aren't as strong as birds). ') but gain speed in short runs because their legs are not configured as in other mammals. Bats prefer high places to perch and rest because they only fall to fly. Species such as the New Zealand shorttail are exceptions because they always live and hunt close to the ground.
The bats' hind legs rotate 90 degrees from the hips and when the knees are bent, they point backwards or to the side. Many insectivorous bats hunt by forming a web-like trap using their legs and the skin membrane between them and the tail.
Horseshoe bats hang by one leg and turn around to see what is going on around them.
A bat hanging or sleeping with its legs (claws) upside down does not make any effort to stay upright, its muscles are relaxed in this position (if it hangs with the fingers, after a while you have to make an effort, we begin to have spasms muscles and we have to let go).
They don't have opposable thumbs, so to minimize the effort needed to bring them together, their fingers are all the same length, some tendons are tense, holding their claws in place (the same mechanism birds use to grab onto a branch when they sleep). ). ) and it is such an effective mechanism that when the bat has to fly to another place, for example to look for food, it has to make an effort to free itself. Researchers who catch bats in nets must also pick them up first, because when they are pulled down, their legs automatically close.
And because the blood doesn't rise to their head or they get dizzy and faint because, unlike us, they have adapted to that position (just like South American sloths and some species of parrots that Asians call bats). parrots sleeping upside down) their size speaks for them we are too big and bulky with too much blood in our stream, all that amount creates pressure and makes us dizzy. In a bat, gravity doesn't affect this fluid in the same way, and hanging doesn't harm it.
© 2022 Rayner Davin