What dinosaurs have to do with human ageing

Human ageing may have been influenced by millions of years of dinosaur domination according to a new theory from a leading ageing expert.

The ‘longevity bottleneck’ hypothesis has been proposed by Professor João Pedro de Magalhães from the University of Birmingham in a new study in BioEssays. The hypothesis connects the role that dinosaurs played over 100 million years with the ageing process in mammals.

While some reptiles and amphibians show no significant signs of senescence, or biological ageing, all mammals including humans show clear signs of ageing.

Professor de Magalhães’ hypothesis suggests that during the Mesozoic Ero mammals faced persistent pressure for rapid reproduction during the reign of dinosaurs, which over 100 million years, led to the loss or inactivation of genes associated with long life in early mammals.

João Pedro de Magalhães, Professor of Molecular Biogerontology in the Institute of Inflammation and Ageing at the University of Birmingham said:

"The 'longevity bottleneck hypothesis' may shed light on evolutionary forces that have shaped the way that mammals have aged over millions of years. While we see humans among different species that are among the longest living animals, there are many reptiles and other animals that have a much slower ageing process and show minimal signs of senescence over their lives.

“Some of the earliest mammals were forced to live towards the bottom of the food chain, and have likely spent 100 million years during the age of the dinosaurs evolving to survive through rapid reproduction. That long period of evolutionary pressure has, I propose, an impact on the way that we humans age.

“We see examples in the animal world of truly remarkable repair and regeneration. That genetic information would have been unnecessary for early mammals that were lucky to not end up as T Rex food. While we now have a plethora of mammals including humans, whales and elephants that grow big and live long, we and these mammals live with the genetic hangups from the Mesozoic era and we age surprisingly faster than many reptiles.

“While just an hypothesis at the moment, there are lots of intriguing angles to take this, including the prospect that cancer is more frequent in mammals than other species due to the rapid ageing process.”