Tuesday, August 18, 2009

NEW UTM STUDY IDENTIFIES FIRST ANCESTOR WITH A GRASPING HAND



The tree-climbing lifestyle of Suminia getmanovi, a Paleozoic animal that lived 260 million years ago, is particularly important because it gave this small herbivore the first access to new food resources high off the ground and also provided protection from ground-dwelling predators. The evidence for this lifestyle is based on several skulls and more than a dozen complete skeletons from central Russia, as well as from coprolites (fossilized feces) that were found on the same sediments as the skeleton. The findings appear online in the Proceedings of the Royal Society B.

"Independently, this animal appears to have acquired this evolutionary innovation of a grasping hand," said Professor Robert Reisz, chair of biology at U of T Mississauga. "That would have allowed it to climb trees very efficiently and to grasp things. It would have allowed the animal to bring food to its mouth." Reisz, the senior author of the paper, notes that modern animals like chameleons and flying lemurs have similar foreleg structure.

The study also provides the first evidence of "resource partitioning" -- with smaller arboreal animals taking advantage of food and safety from predators in trees while larger herbivores remained on the ground. This was a change from a large numbers of terrestrial plant-eaters supporting a few top predators and even earlier terrestrial vertebrate communities composed of various sized predators and relatively few herbivores.

(Photo: UTM)

University of Toronto Mississauga

0 comentarios:

Post a Comment

Followers

Archive

 

Selected Science News. Copyright 2008 All Rights Reserved Revolution Two Church theme by Brian Gardner Converted into Blogger Template by Bloganol dot com