Australian Snake Fossil Found

The fossil bones of a giant snake that thrived in Australia some 30 million years ago have added a link to the story of reptile evolution, Australian scientists report.

And with a touch of irony, it appears that the reptile’s primitive tribe descended from early lizards, but its later descendants in the snake family ate lizards as a regular part of their diet.

An extraordinarily well-preserved skull of a snake that scientists have named Yurlunggur was excavated recently at a fossil- rich site near the Australian mining town of Mount Isa, deep in the outback more than 1,000 miles northwest of Brisbane, and its features are described Thursday in the British scientific journal Nature.

The strange name is an aboriginal word for the mythological “Great Rainbow Snake” of the native Australians. Yurlunggur, according to aboriginal legend, created Australia’s lakes, rivers and water holes and was also a fertility goddess.

John Scanlon, a paleontologist who reported on the snake’s structure in Nature, said the skull should help scientists “understand the origin and early evolution of snakes from lizards” – a puzzle that has eluded researchers because the skeletons of long- extinct snakes are so fragile and rare.

Scientists have known that ancient varieties of lizards were the ancestors of the snake family, and the new skull and its clearly defined structure add fresh insights into how the reptiles changed as they evolved, Mr. Scanlon said.

Yurlunggur, he said in an e-mail, helps provide “a useful fossil record of extinct primitive snakes, illustrating their transformation from lizards.”

The snake apparently existed during the millions of years when a huge supercontinent that scientists call Gondwanaland existed in a southern ocean called Tethys. It comprised what are now the separate continents of Australia, Antarctica, Africa and South America.

“It seems likely that the snakes like Yurlunggur originated here,” said Mr. Scanlon, a paleontologist at the Riversleigh Fossil Centre and South Australian Museum in Adelaide, “either on land or near the Gondwana coast of the Tethys Sea.”

Mr. Scanlon and his colleagues at the University of Queensland have also reported discovering the badly crushed fossil bones of another primitive snake they named Wonambi – the aboriginal word for a similar mythical “Great Rainbow” serpent. That one, they said, emerged around 100 million years ago – long before Yurlunggur – and might not have become extinct until 50,000 years ago. It “could have overlapped with human history in Australia,” they said.

The first aborigine people are believed to have reached Australia from the Asian continent sometime between 60,000 and 40,000 years ago.