A new study has found that man’s best friend evolved from small, mongoose-like animals. They went from being typical forest dwellers to being pursuit-pounce predators due to climate change.
The research team reached this conclusion by looking at fossils of North American dogs dating back 40 million years. The fossils resemble modern day mongooses a lot more than they do modern day dogs, and the ancient animals are believed to have had forelimbs that weren’t made for running, but for grappling prey.
The study has made many field experts wonder how the recent human-caused climate change will affect animal species on our planet in the years to come. A recent study has already found that certain types of lizards are switching their gender and moving towards becoming entirely female species.
And the new study has shined a light on how animals that were previously considered prey can evolve into predators.
Christine Janis, study co-author and professor of evolutionary biology and ecology from Brown University, gave a statement saying that the findings are “reinforcing the idea that predators may be as directly sensitive to climate and habitat as herbivores”. She went on to add that “Although this seems logical, it hadn’t been demonstrated before”.
Professor Janis also informed that the study reinforces the theory that dogs (the entire Canidae family) originated from North America. They lived here for a good, long time, and only spread to Africa and Eurasia about 7 million years ago. South America only saw its first dog about 2 million years ago.
However, the co-author did point out that the only the Canidae family got out of North America. The Borophaginae and Hesperocyoninae remained exclusive to the point of origin.
For their study, professor Janis, Borja Figueirido, lead author and professor from the Universidad de Málaga (Spain), and the rest of their colleagues analyzed the teeth and elbows of 32 different species of dogs. Some of them dated back 40 million years, while other only dated back 2 million years.
Professor Janis explained that the elbow is a really great indicator of how carnivores are evolving their forelimbs as it reveals their locomotion repertoire.
And comparing these changes in the animals’ forelimbs to changes in the climate help the research team realize that these evolutionary movements coincided with one another. Once the temperatures became dryer and started to cool down, the grasslands opened up, and the members of the Canidae family went from being ambush predators to being pursuit-pounce predators like modern day coyotes and foxes.
And soon after that, they turned into so-called “dogged, follow-a-caribou-for-a-whole-day pursuers” such as wolves.
Their limbs went from being designed for grappling prey to being designed for running, and their teeth became more durable, perhaps because the animals now had to sink them into prey that lived in the gritty savannahs, rather then into prey that lived in damp forests.
Professor Janis also theorized that members of the Canidae family did not develop the ability to run because prey such as antelope and deer were much faster than what they were used to hunting, but simply because they now had the space to run. During the warmer past, they could not have done so due to the danger of bumping into trees.
The findings were published recently in the journal Nature Communications.