..... like can you explain me bat's back legs??? Are they actually backwards?
Simplified answer: yes. Look at the bat below- the bottoms of her feet are facing forwards and her knees pointing backwards.
Longer answer: Compared to other mammals, the legs of bats are rotated 90-180 degrees in the hip socket at rest (depending on the species). However, all bats hold their legs out from their body facing backwards while flying, because their legs are a crucial component of their wing.
They also use the membrane between their legs to scoop up bugs. This would be impossible if their knees bent in the other direction.
Below are a couple of bat embryos which do a good job of demonstrating how whack their legs are (try to imitate this pose, if you dare).
To really see how stupid their pelvises and legs have become, just look at a bat skeleton…
…and compare it to the skeleton of an animal that makes sense, like a shrew.
Some species of bats can pull their legs up alongside their body to crawl, in kind of a frog-pose, though because of their pelvis shape they can’t pull them far enough underneath their body to lift their stomachs off the ground, and are forced to walk using an awkward sideways shuffle, or if their legs are extra pathetic, a sort of breaststroke using their wings to push off the ground.
Vampire bats are among the only bats to have evolved an upright walk, with their feet pointing backwards.
New Zealand short-tailed bats are the other expert walkers, though they evolved a completely different gait than the vampire bat, with their feet positioned more sideways like awkward little ducks.
In summary, bat legs are Goofy As Fuck and I adore them.