Armless fossil sheds light on how animals like snakes lost their limbs

By Christa Lest.

Some of their descendants lost their legs again after 100 million years after the first growth of legs. The discovery shows that land animals first evolved into snake-like forms at least 300 million years ago.

Two fossils of an ancient animal, both of which came from rocks in Illinois, were found by Arjan Mann and his colleagues at the National Museum of Natural History in Washington DC.

The animal has been named Nagini mazonense and is a new species in the molgophids. It may have been 10 centimetres long and had no fore limbs. It lacked the structures that support the attachment of forelimbs to the body.