A University of Alberta palaeontologist has helped discover the existence of a 95 million-year-old snakelike marine animal, a finding that provides not only the earliest example of limbloss in lizards but the first example of limbloss in an aquatic lizard.
"This was unsuspected. It adds to the picture we have of what was happening 100 million years ago. We now know that losing limbs isn't a new thing and that lizards were doing it much earlier than we originally thought. On top of that, this lizard is aquatic. All the examples we have in our modern world are terrestrial, so it's a big deal" - Dr. Michael Caldwell, from the U of A's Faculty of Science.
The evidence offers the earliest record of vestigial limbs—once used in an animal's evolutionary past but that has lost its original function-- in a fossil lizard. The newly named species--Adriosaurus microbrachis--is described in the current issue of the Journal of Vertebrate Palaeontology and offers clues to the evolution of terrestrial lizards as they returned to water. The fossil was originally collected during the 19th Century from a limestone quarry in Slovenia. It then sat at the Natural History Museum in Trieste, Italy for almost 100 years before Caldwell and a colleague found it in 1996 during a trip to Europe. He later connected with Alessandro Palci, then a graduate student in Italy whom he helped supervise, and they worked on the fossil together.
