Some dinosaurs became warm-blooded to survive climate change

Long considered cold-blooded behemoths, new research challenges the conventional wisdom about dinosaurs. The study suggests that some of these ancient creatures may have been warm-blooded, a revelation that could rewrite our understanding of their evolutionary history and physiology.

Climate impact on dinosaurs’ warm-blooded traits

Picture this: It’s the Early Jurassic period. Intense volcanic activity triggers a global warming event known as the Jenkyns event. This dramatic climate shift leads to the extinction of various plant species. It paves the way for the emergence of many new dinosaur groups.

But what’s truly remarkable is the impact of this environmental crisis. It may have been the catalyst for endothermy, which is the ability to internally generate heat. This trait is a defining characteristic of mammals and birds.

Endothermy allowed certain dinosaurs to thrive in changing climates. This adaptation enabled them to maintain high activity levels and survive in colder environments. The evolution of endothermy marks a significant turning point in dinosaur physiology. It highlights their incredible ability to adapt to environmental challenges.

“Our analyses show that different climate preferences emerged among the main dinosaur groups around the time of the Jenkyns event 183 million years ago,” explained study lead author Dr. Alfio Alessandro Chiarenza of UCL Earth Sciences.

“The adoption of endothermy, perhaps a result of this environmental crisis, may have enabled theropods and ornithischians to thrive in colder environments.”

Theropods and ornithischians

Theropods, the group that includes the iconic T. rex and Velociraptor, and ornithischians, which include relatives of the plant-eating Stegosaurus and Triceratops, were the first to embrace this newfound ability to regulate their body temperature.

This allowed the dinosaurs to venture into colder climates, where they could remain active for longer periods, grow faster, and produce more offspring.

“Theropods also include birds and our study suggests that birds’ unique temperature regulation may have had its origin in this Early Jurassic epoch,” noted co-author Dr. Sara Varela of the Universidade de Vigo.

But what about the other major dinosaur group, the sauropods? These gentle giants, including the Brontosaurus and Diplodocus, opted to stick to warmer climates. They achieved this by growing to enormous sizes, which helped them retain heat due to their smaller surface area to volume ratio.

“Sauropods, on the other hand, which stayed in warmer climates, grew to a gigantic size at around this time – another possible adaptation due to environmental pressure,” said Dr. Varela. “Their smaller surface area to volume ratio would have meant these larger creatures would lose heat at a reduced rate, allowing them to stay active for longer.”

Dinosaur revolution from cold to warm-blooded

This study fundamentally challenges the long-held notion that all dinosaurs were cold-blooded. It reveals a more complex picture of their physiology. Dinosaurs were not uniform in thermoregulation. They showcased diverse adaptations to their environments.

The evolution of endothermy, or warm-bloodedness, occurred in theropods and ornithischians during the Early Jurassic period. This development was potentially triggered by environmental pressures like the Jenkyns event. It gave them a significant edge over their cold-blooded counterparts.

This adaptation allowed dinosaurs to thrive in colder climates. It drove their diversification and success. The ability to internally regulate body temperature was pivotal in dinosaur evolution. This trait potentially contributed to the rise of birds – the only surviving dinosaur lineage.

This new understanding of dinosaur physiology opens up intriguing research avenues. It prompts scientists to re-evaluate long-held assumptions about their biology, behavior, and evolutionary trajectories.

Warm-blooded dinosaur evolution

While this study offers fascinating insights into the evolution of warm-blooded traits in dinosaurs, many questions remain unanswered. For instance, researchers are still unsure exactly how this adaptation occurred and what other factors may have contributed to its emergence.

“This research suggests a close connection between climate and how dinosaurs evolved,” said co-author Dr. Juan L. Cantalapiedra of the Museo Nacional de Ciencias Naturales. “It sheds new light on how birds might have inherited a unique biological trait from dinosaur ancestors and the different ways dinosaurs adapted to complex and long-term environmental changes.”

As researchers continue to delve into the mysteries of dinosaur evolution, one thing is certain. These ancient creatures were far more complex and fascinating than we ever imagined. Their ability to adapt to diverse environments showcases their evolutionary ingenuity.

Each new discovery adds layers to our understanding of dinosaur biology and behavior. Fossil evidence continues to surprise scientists with unexpected traits and adaptations. Advances in technology and methods allow for deeper exploration of their physiology.

And who knows what other surprises they might have in store for us? The world of dinosaurs remains full of undiscovered secrets waiting to be unveiled.

The study is published in the journal Current Biology.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–