Re: Do animals have navels?

All placental mammals have navels, which are simply scars left at the site where the umbilical cord was attached to the body. While the point is subject to much debate, there is evidence that several other amniotes hatch from their eggs still attached to their egg blood vessels through an allantoic stalk homologous to the umbilical cord. Hence, birds and reptiles may be considered to have "navels" (or at least something homologous to a navel) as well.

For more on this, check out these previous answers:

Do elephants have navel?
feline and canine belly buttons
Re: Feline/canine bellybuttons
What exactly flows through the umbilical cord?
When the umbilical cord enters the foetus, which vein does it enter?
How does a baby chick know to peck it's way out of an egg?

Placenta

A large, vascular structure, through which the embryo gets nutrients and exchanges gases with the mother's uterus.

Mammal

Any of a class of warm-blooded vertebrates with hair and mammary glands.

Umbilical cord

The flexible cordlike structure connecting an embryo at the navel with the placenta and containing two umbilical arteries and one vein that transport nourishment to the embryo and remove its wastes.

Amniote

Any of a group of land vertebrates that develop extensive, vascular membrane systems outside of the embryo during gestation; includes reptiles, birds, and mammals.

Allantois

A vascular, membranous structure similar to and arising after the yolk sac, used for waste disposal and gas exchange in amniotic eggs.