Newborn red kangaroos are less than an inch long
Darren Orf – A baby red kangaroo (Macropus rufus) is about the size of a jelly bean. Born after about 34 days of gestation, it’s less than an inch long — or 100,000 times smaller than its adult height (roughly 4 feet).
This newborn kangaroo, called a joey, isn’t quite ready for prime time, however. Unlike most mammals, joeys are born while they’re still embryos, which means they lack sight, hearing, and hair. They spend the next six months in their mother’s pouch, or marsupium, where they suckle from a teat and continue to develop before finally taking their first steps into the world.