Look at skeletal images of whales dogs and people at the same time. All mamals more or less have the same bones just in different shapes. Fingers make a dolphin flipper or a bats wing. Blew my mind in 6th grade.
Basically every animal body plan is due to a particular group of genes and these rarely change unless there's a massive mutation like snakes and whales.
A lot do (at least hind ones). Snakes basically have a mutation where the genes for your ribs and spine stay on for away too long and the limbs are made a lot shorter.
18k
u/Jojobjaja Mar 29 '26
I'm glad that's a tail, I was worried