185 million year fossils of ancient organisms have 38 children

Fossils discovered in the US help scientists better understand the process of breast evolving brain size.

Scientists discovered fossils of an extinct creature with herds of 185 million years ago, providing evidence that mammals trade off the ability to produce multiple babies with large brains during evolution. , Fox News reported today. This is the only fossil with the offspring of this creature ever discovered, according to researchers at the University of Texas.

Illustrations of fossil creatures with surname with mammals and cubs.(Photo: Eva Hoffman / University of Texas).

"New discoveries are extremely rare and can greatly affect mammalian research," said expert Greg Wilson at the University of Washington.

Fossil creatures called Kayentatherium wellesi, belong to the sub-division of dogs, relatives of mammals and live in Jurassic period. Its number of children is several times that of mammals today, showing that K. wellesi can reproduce similarly to reptiles.

Experts did not find any eggshell at the point. After analysis, they thought that the offspring may be growing inside the egg or just hatching before dying and turning into fossils.

"These babies come from a very important time in evolutionary history. They have many similar characteristics to modern mammals, helping scientists better understand the evolution of mammals , " Eva said. Hoffman, the head of the study, explained.

Kayentatherium wellesi with fertility many times more than mammals today.(Photo: Eva Hoffman / University of Texas).

This ancient fossil was found by Timothy Rowe, a professor at the University of Texas and a member of the research team, in northeastern Arizona, USA, over 18 years ago. At first, Rowe claimed that the excavated rock contained only one specimen.

However, scientist Sebastian Egberts discovered tooth enamel on the fossil in 2009. " It is not like a sharp tooth or small reptilian tooth that looks more like molar teeth. It makes me very excited." , Egberts share.

The scans showed that the rock contained not only a mother's specimen but also the pieces of the skull of the cub. The K. wellesi has small brains and many children show that mammals do not trade off fertility with brain development in the early Jurassic period. This transition took place several million years later.