All placental animals have belly buttons.
Dolphins are placental mammals. All placental mammals have bellybuttons of some kind.
Cats are placental mammals, and all placental mammals have bellybuttons of some sort.
Mammals, yes.
As a matter of fact, dolphins do have bellybuttons. All mammals have them because that is where their umbilical cord was connected.
No. Only mammals have belly buttons.
No. The belly button is a trait only found in mammals.
Yes, because they are mammals and are born live.
Ponies, like all horses are placental mammals. ANd all placental mammals have bellybuttons of some sort.
Yes, they do eat bellybuttons. It's their favorite food!
Mammals (other than monotremes) have navels. Other animals do not, because they have no use for them.
no
Yes.