A recent study has revealed that man’s best friend looked very different 40 million years – like small, mongoose-like animals. They lived in forest environments and had stiffer limbs that were not designed for running. What turned them into pursuit-pounce predators you may ask? Climate change.
The researchers came to this conclusion after looking at fossils of 32 different species of dogs from North American. Some of them belonged to animals that lived 40 million years ago, while other belonged to animals that only lived 2 million years ago.
They wide variety helped experts better understand how and why dogs evolved into the animals we know and love today. The fossils informed that the ancient animals resembled present day mongooses much more than they did present day dogs.
The researcher team was especially interested in studying the elbows and the teeth of the fossils. The experts explained that the elbows of predators offer really great clues to how the animals evolved their forelimbs over the decades because it relates to their locomotion repertoire.
After comparing changes in the climate to the changes in the animals’ forelimbs, they saw that the two coincided. Once the temperatures started to cool down, open grasslands were created, and dogs went from having forelimbs that were designed for grappling prey (they used to be ambush predators) to being pursuit-pounce predators that can run at high speeds.
They basically started to resemble modern day foxes and coyotes. Their teeth also underwent chances and became more durable as the animals had to start sinking them into savannah prey, rather than forest prey.
Soon after this they evolved into wolves, or what the research team described as “dogged, follow-a-caribou-for-a-whole-day pursuers”.
The study has made scientists wonder how the recent climate change caused by human activity may affect the animals living on our planet. A study from a couple of months ago has already shown that certain types of lizards are adapting to the warmer climate by changing their sex from male to female. Field experts have speculated that we may end up getting some entirely female species.
And the new study shines a light on how carnivorous predators can evolve to adapt to different climates.
Christine Janis, co-author on the study and professor of ecology and evolutionary biology from Brown University, gave a statement informing that the study is “reinforcing the idea that predators may be as directly sensitive to climate and habitat as herbivores. Although this seems logical, it hadn’t been demonstrated before”.
She went on to say that the findings also reinforce the notion that dogs originated in North America. Researchers have proven that dogs have only had a presence in Eurasia and Africa for about 7 million years. And as far as South America goes, the region has only had dogs for a mere 2 million years.
What’s more, Professor Janis also pointed out that the Canidae family is the only one to get out of North America. The Borophaginae family and the Hesperocyoninae family have not spread to other regions.
The study was published in the journal Nature Communications.
Image Source: animalia-life.com