Mammals evolved fastest during mid-Jurassic era: Study

London, July 20 (IANS) Mammals underwent a rapid ‘burst’ of evolutionary change that reached its peak around the middle of the Jurassic age around 145-200 million years ago, a study says.

The findings suggest that different body shapes and functions in mammals evolved rapidly during this period.

“What our study suggests is that mammal ‘experimentation’ with different body-plans and tooth types peaked in the mid-Jurassic,” said study lead author Roger Close from Oxford University.

Early mammals lived alongside the dinosaurs during the Mesozoic era (252-66 million years ago).

They were once thought to be exclusively small nocturnal insect-eaters, but fossil discoveries of the past decade – particularly from China and South America – have shown that they developed diverse adaptations for feeding and locomotion, including gliding, digging, and swimming.

To find out when and how rapidly these new body shapes emerged, the researchers did a large-scale analysis of skeletal and dental changes in Mesozoic mammals.

By calculating evolutionary rates across the entire Mesozoic, they showed that mammals were evolving up to ten times faster in the middle of the Jurassic than they were at the end of the period.

“Once high ecological diversity had evolved, the pace of innovation slowed,” Close said.

Multituberculates, for instance, saw radical changes to their skeletons and teeth during the mid-Jurassic. However, by the end of the period they had evolved their rodent-like body shape and distinctive teeth, a form that, despite diversifying into hundreds of different species, they would generally retain until they went extinct around 130 million years later.

“In the Jurassic, we see a profusion of weird and wonderful bodies suddenly appear and these are then ‘winnowed down’ so that only the most successful survive,” Close said.

Leave a Reply

Please enter your comment!

The opinions, views, and thoughts expressed by the readers and those providing comments are theirs alone and do not reflect the opinions of www.mangalorean.com or any employee thereof. www.mangalorean.com is not responsible for the accuracy of any of the information supplied by the readers. Responsibility for the content of comments belongs to the commenter alone.  

We request the readers to refrain from posting defamatory, inflammatory comments and not indulge in personal attacks. However, it is obligatory on the part of www.mangalorean.com to provide the IP address and other details of senders of such comments to the concerned authorities upon their request.

Hence we request all our readers to help us to delete comments that do not follow these guidelines by informing us at  info@mangalorean.com. Lets work together to keep the comments clean and worthful, thereby make a difference in the community.

Please enter your name here