Study decodes how different forms of backbones came into existence

A recent study published in the journal Nature Ecology and Evolution revealed how and when changes in spine happened during the evolution of mammals. Researchers found out how different forms of backbones came into existence in several modern terrestrial animals. The study further found the developmental changes in the extinct ancestors of mammals which laid the groundwork for the diverse forms of backbones. 

According to reports, researchers from Harvard University compared the bone and muscle movement patterns of two modern animals — cat and lizard — and the X-ray scans of fossils belonging to the mammal ancestor, the synapsid, which have gone extinct around 252 million years ago. The researchers further assessed how animals' spinal joints bent in different directions. They revealed that while some spinal regions can function differently, others do not. 

READ: Fireflies Facing Extinction Due To Artificial Lighting Created By Humans: Study

The study cited an example of the backbone of the lizard which comprised several distinct regions, but they all acted in the same way. The researchers believe that the findings have overturned the traditional notion that the gradual accumulation of different regions of the spine alone accounts for its evolving complexity. They noted that the regions like lower back evolved long before new spinal functions, such as bending and twisting. 

Co-author Stephanie Pierce from Harvard University said, “What we were able to show in 2018 was that even though all the vertebrae looked very similar in early mammal ancestors they had subtle differences and those subtle differences created distinct developmental regions,” She further added, What we''re showing with this new study is that those distinct regions were really important as they provided the raw material that facilitated functional differentiation to happen”. 

READ: Melodic Alarm Tunes May Help You Wake Up Better In The Morning: Study

Fundamental evolutionary question

She further explained that without the distinct developmental regions in place, all the backbones may have adapted in the same way under selective pressure. Pierce, in her study, also showed that an evolutionary trigger was also required and in this case the evolution of a highly active lifestyle that put new demands on the backbone. With this study, the researchers tried to explain that if two joints in the spine looked different, then they tended to have different functions. 

Co-author Katrina Jones said, “We're trying to get at something that's quite a fundamental evolutionary question which is: How does a relatively simple structure evolve into a complex one that can do lots of different things? Is that determined by the limitations of development or natural selection related to the behaviour of the animal?”

(With PTI inputs)

READ: Study Shows Black Panther Fur Colour Affects It's Communication

READ: Study Claims Avocados Keep Obesity In Check, Boosts Health