Scientists report the genetic makeup of the platypus

Scientists believe the platypus and humans shared an evolutionary path until about 165 million years ago when the platypus branched off. Unlike other evolving mammals, the platypus retained characteristics of snakes and lizards, Graves said.

By comparing platypus genes to those of humans and other mammals, scientists hope to fill in the gaps about mammals' evolution and better identify species' specific traits.

Unique to Australia, the platypus has confounded observers for centuries. Aboriginal legend explained the notoriously shy animal as the offspring of a duck and an amorous water rat.

When the British Museum received its first specimen in 1798, zoologist George Shaw was so dubious he tried to cut the pelt with scissors to make sure the bill had not been stitched on by a taxidermist.

Platypuses live along most of Australia's east coast and though their numbers are not accurately known they are not considered to be endangered.