SYDNEY: With a bill like a duck, a tail and fur like a beaver and snake-like venom hidden in heel spurs, the platypus could be the result of some strange genetic experiment.

It is: evolution.

Scientists on Thursday published the genetic makeup of the Australian animal in the scientific journal Nature, confirming that its multifaceted features are reflected all the way down to its DNA.

The research could help explain how mammals, including humans, evolved from reptiles millions of years ago, they said.

“At first glance, the platypus appears as if it was the result of an evolutionary accident,” said Francis S. Collins, director of the US National Human Genome Research Institute, which funded the study.

“But as weird as this animal looks, its genome sequence is priceless for understanding how mammalian biological processes evolved,” Collins said in a statement.

The platypus is classed as a mammal because it has fur and feeds its young with milk. It flaps a beaver-like tail. But it also has bird and reptile features it lays eggs, has a duck-like bill and webbed feet. Males have spurs on their heels that inject pain-causing venom to ward off mating rivals.

More than 100 scientists from the United States, Australia, Japan and other nations took part in mapping the genome, using DNA collected from a female platypus named Glennie from a farm in central New South Wales state.

Jenny Graves, an Australian National University genomics expert who co-wrote the paper, said the gene sequencing showed the platypus has a mix that crosses different classifications of animals.

“What we found was the genome, just like the animal, is an amazing amalgam of reptilian and mammal characteristics with quite a few unique platypus characteristics as well,” she told the Australian Broadcasting Corp.

The genetic links between platypuses and mammals that the scientists found include lactation and fur, while laying eggs and venom production tie the animals to reptiles.

Scientists believe mammals evolved from reptiles, and the animals that became platypuses and those that became 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.With Australia’s echidna, platypuses form the biological classification monotreme, or egg-laying mammals.The research adds the platypus to the growing list of animals whose genetic makeup has been unravelled.

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

Des Cooper, an evolutionary biologist at the University of New South Wales who did not take part in the research, said it represented a big step forward in the world’s knowledge of mammals.

“Platypuses are often thought of as primitive because they lay eggs,” Cooper said. “This paper demonstrates there is a mixture of characters which they share with other mammals and of highly specialized attributes.”

Graves said the research contained some surprises, such as the conclusion that genes that determine sex in a platypus are similar to those of a bird, not a mammal. Researchers also found genes that indicate platypuses which rely on electro-sensory receptors in their bills to navigate as they rummage with closed eyes in waterways may also be able to smell underwater.

Unique to Australia, the platypus has confounded observers for centuries. Aboriginal legend explained it 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 in the wild along most of Australia’s east coast. Their numbers are not accurately known because they are notoriously shy. Hunted for years for their pelts, they have been protected since the early 1900s and are not considered to be endangered, though scientists say their habitat is vulnerable to human development. —AP