{"id":11114,"date":"2022-03-31T19:00:25","date_gmt":"2022-03-31T17:00:25","guid":{"rendered":"https:\/\/www.sciencefocus.com\/?p=115963"},"modified":"2022-03-31T19:07:12","modified_gmt":"2022-03-31T17:07:12","slug":"prehistoric-mammals-bulked-up-to-survive-in-the-changing-post-dinosaur-world","status":"publish","type":"rss_feed","link":"https:\/\/c01.purpledshub.com\/bbcsciencefocus\/rss_feed\/prehistoric-mammals-bulked-up-to-survive-in-the-changing-post-dinosaur-world\/","title":{"rendered":"Prehistoric mammals bulked up to survive in the changing post-dinosaur world"},"content":{"rendered":"

<\/p>

By Jason Goodyer\n \t\t<\/p>

Published: Thursday, 31 March 2022 at 12:00 am<\/p>

\n\n

In the first 10 million years after the extinction of the dinosaurs, mammals developed bigger bodies to help cope with the radical changes that were occurring on Earth, researchers at the University of Edinburgh have found.<\/p>\n

To make the discovery, the team CT-scanned a collection of complete skulls and skeletons of mammals that lived immediately after the mass extinction of dinosaurs<\/a> discovered in the badlands of north-western New Mexico.<\/p>\n

It was previously thought that mammals\u2019 relative brain sizes, the size of their brains in relation to their bodies, increased following the catastrophic asteroid impact that ended the reign of dinosaurs 66 million years ago. The theory being that bigger brains would have allowed the prehistoric mammals to take advantage of any new opportunities that opened up as the dinosaurs died out.<\/p>\n

\"""\"<\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/source><\/picture><\/div>
Cranium of Arctocyon<\/em>, a mammal that lived during the Paleocene Ornella Bertrand and Sarah Shelley (left), and Hyrachyus<\/em> , a mammal that lived during the Eocene 55 to 34 million years ago (right) \u00a9 Ornella Bertrand and Sarah Shelley<\/span><\/figcaption><\/div>\n

However, the team\u2019s findings show that the relative brain sizes in fact decreased at first due to early mammals\u2019 rapid increase in body size<\/a>.<\/p>\n

Results of scans also suggest the animals relied heavily on their sense of smell, and that their vision and other senses were far less well developed.<\/p>\n

\u201cLarge brains are expensive to maintain and, if not necessary to acquire resources, would have probably been detrimental for the survival of early placental mammals in the chaos and upheaval after the asteroid impact,\u201d said lead researcher Dr Ornella Bertrand<\/a>.<\/p>\n

It wasn\u2019t until around 10 million years after the extinction of the dinosaurs that early members of modern mammal groups such as primates began to develop larger brains and a more complex range of senses and motor skills.<\/p>\n

\u201cThe mammals that usurped the dinosaurs were fairly dim-witted, and only millions of years later did many types of mammals develop bigger brains as they were competing with each other to form new ecosystems,\u201d added senior author Professor Steve Brusatte<\/a>.<\/p>\n

\n

Read more about dinosaurs:<\/strong><\/p>\n