The common protein found in all animals is collagen.
They are all animals
All animals have to go throw pregnancy first which is common in all female animals.
Deserts occur on all seven continents and there are no animals common to all.
2 common animals are the raccoon and the bear
Teeth because all animals need to chew their food.
All animals in antarctica have fat deposit under their skin.
they all have brains
they are animals and that's it
Genitals
they are all animals
Cell walls !