Dogs Evolved as Hunters due to Climate Change

There’s a lot of irony involved, however, because according to researchers at Brown University, several million years ago it was early dogs who evolved to be more like cats – not the other way around.

Christine Janis, a professor of ecology and evolutionary biology at Brown University and co-author of the study, said the study reinforces the idea that predators are as sensitive to climate change as herbivores. “We selected the shape of the elbow because it is an established anatomical indicator of locomotor/predatory behaviour in living carnivores, as it reflects the relative range of forearm motion”, affirmed study’s lead researcher Borja Figueirido of Universidad de Málaga.

Our modern day domesticated dogs do not have the need to hunt for their own food and thus it is arguable if our current climate change will have much of an impact on them. However, after a few million years, the thick forests which covered North America began to disappear and gave way to grasslands when conditions became cooler and drier.

“The elbow is a really good proxy for what carnivores are doing with their forelimbs, which tells their entire locomotion repertoire”, Janis explained.

The authors of the study also pointed out that if predators evolved with climate change, then they are likely to continue to evolve with the climate change that is going on now. South America only saw its first dog about 2 million years ago. Upon examination of the over 32 species of fossils it was determined that the dog’s elbow joints and forelegs evolved to facilitate long-distance running, offering more support and less flexibility.

Aside from better forelimbs for running, the scientists also observed that climate change influenced the teeth of the dogs.

Older canine species tended to have paws that could swivel inwards or down to help them grab and wrestle prey, a similar structure can still be seen in the limbs of modern cats. These animals were well-suited for a warm, heavily wooded climate – which was the climate of North America at the time. “Therefore, long periods of profound climatic change are critical for the emergence of ecological innovations, and could alter the direction of lineage evolution”. After all, it wasn’t advantageous to operate as a pursuit-and-pounce predator until there was room to run. Their findings were recently published in the journal, Nature Communications. And this was occurring at a time our climate was changing the vegetation of the land. If they would have attempted to do so in the forest environment, they would have smacked straight into a tree.