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Lizards that lost their legs evolved as the climate got more humid

By Christa Lesté-Lasserre

Brachymeles bicolor has short and blunt legs

Historical collection / Alamy

In the distant past, climate change may have caused limbless lizards to develop legs – after losing them once.

The once four-legged, ancient lizards of the genus Brachymeles first appeared in a dry environment in what is now Southeast Asia. They dropped all four limbs about 62 million years ago, but about 40 million years later some species regrown them, says Philip Bergmann of Clark University in Worcester, Massachusetts.

“Around the time these lizards went from serpentine to newly developing limbs, there was this climate change from an environment that is much drier …