Editor's Summary

20 April 2006

How snakes got snake-like

Think 'snake', and a limbless reptile comes to mind. But it wasn't always so. Some fossil snakes with external limbs are known, and enough fossils have been found to show that limb loss in snakes was not a simple, gradual process. A newly discovered fossil from the Cretaceous of Argentina bears not only robust hindlimbs but — never seen before in a snake — a sacral region that allowed the limbs to articulate with the backbone. This is probably the most primitive snake yet known, and its anatomy suggests a terrestrial, burrowing origin for snakes, rather than the marine origin often suggested.

LetterA Cretaceous terrestrial snake with robust hindlimbs and a sacrum

Sebastián Apesteguía and Hussam Zaher


Extra navigation

  • Japanese table of contents