A group of scientists who analyzed the North American dog fossils as old as 40 million years found that the evolutionary path of prehistoric dogs was a result of climate change. In fact, the evolution of whole groups of predators was a direct consequence of climate change, according to a new study published in the journal Nature Communications.
North America’s climate was warm and wooded 40m years ago
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. The climate was warm and wooded in North America’s heartland about 40 million years ago. That means a dense, extensive forest in what we now know as the Central Plains of the United States.
At the time, the species were small animals, unlike any dogs alive today. The native dogs were ambush predators about 40 million years ago. Their forelimbs were not suited for running. But things began to change a few million years later. The global climate change made the area more cool and dry. The dense forests thinned out, giving way to open grasslands.
Climate change affects both predators and their prey
As the climate change was opening up the vegetation, herbivores evolved and long-legged animals like deer proliferated. The dogs also evolved from ambushers to pursuit-pounce predators like foxes and coyotes, and eventually into wolves. After all, it made no sense to operate as a pursuit-and-pounce predator until there was sufficient room to run.
Scientists said that the wild dogs’ evolution tracked in time directly with the climatic changes in the habitat rather than the anatomy of their prey species. The dogs’ forelegs became specialized for long-distance running, and their teeth became more durable.
Scientists examined fossils of 32 species of dogs from 40 million years ago to 2 million years ago. The study suggests that climate change has a dramatic impact on both predators and their prey.