A FOSSIL snake with well-developed rear limbs has fired the debate over
whether snakes’ ancestors lived on land or in the sea.
The 95-million-year-old Haasiophis terrasanctus was found in marine
deposits north of Jerusalem. In 1996, researchers who studied a similar legged
snake called Pachyrhachis decided that it was an ancestral snake that
had never lost its rear legs. As Pachyrhachis was a sea predator, they
concluded that it—and all snakes—had evolved from marine lizards
called mosasaurs
(New Scientist, 30 November 1996, p 17).
But Olivier Rieppel of the Field Museum in Chicago thinks they got it…
