LSU helps decode DNA: Platypus is mammal, bird, reptile

• By JORDAN BLUM
• Advocate Capitol News Bureau
• Published: May 8, 2008 - Page: 1B - UPDATED: 12:05 a.m.

• Print
• Email
• Save
• Reprints
• Twitter
• Share

• Del.icio.us
• Digg
• Facebook
• Reddit
• 

When the platypus was first observed by Europeans about 200 years ago, many considered the bizarre animal a hoax.

But now an international research team — including LSU — has decoded the unusual animal’s DNA, highlighted on the cover of this week’s issue of the scientific journal Nature.

The platypus is a mammal that also is part bird and part reptile. It combines a furry mammal body with a duck bill, beaver tail, webbed feet, lactating glands and even venom strong enough to kill a dog.

To top off the list of oddities, the platypus also is one of the rare egg-laying mammals.

Mark Batzer, LSU professor of biological sciences, said the “fine-feathered or furry friend” was a fascinating “patchwork” animal to study.

“It’s kind of like the last car built on a Friday,” Batzer said. “When you take parts from three models and piece them all together.”

The platypus represents one of the few surviving links to early mammalian evolution, he said, and thus tells scientists a lot about what genetically makes up a mammal.

“It (the platypus) is in a unique position in the tree of life,” Batzer said.

Very little is known about the animal because it is relatively endangered, mostly lives in Australia and Tasmania and does not like to breed in captivity.

“It’s fairly rare to see them out in the wild because they’re relatively shy and there’s not many of them,” Batzer said.

Batzer was one of the primary researchers in a large international team led by Washington University in St. Louis.

Among the unusual occurrences noted in the Nature article are the platypus’ snakelike venom DNA, its milk-producing glands without nipples that developed more than 150 million years ago and a chickenlike yolk in its eggs.

Deoxyribonucleic acid, or DNA, is a nucleic acid molecule that contains genetic instructions.