The biome lent itself to predators that were smaller and could ambush by surprising their prey while they were passing by, which describes the wild dogs native to that period.
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Scientists studying dogs that lived in North America millions of years ago found that climate change seems to have been a key factor in their evolution.
Forty million years ago, much of the Central Plains of the United States had dense, extensive forest with a warmer and wetter climate.
The change led to a transformation in dogs, turning them into animals that no longer surprised their prey but chased them down.
During the study, the experts involved the analysis of the elbows and teeth of as many as 32 species of dogs that were alive about 40 million years ago. But the predators evolved with this shift in habitat too, as study determined from close inspection of the fossil records.
Eventually, the middle part of North America dried out such that we got the grassy plains we know today. The lead author of the study is Borja Figueirido, a former Brown Fulbright postdoctoral researcher. A lot of the main evolution points of these animals occurred in tandem with major shifts in the climate.
To determine whether there was a correlation between the evolution of canids and the overall cooling in climate, researchers examined fossils of both living and extinct canids from over the past 37 million years.
Two species of early dog, Hesperocyon and Sunkahetank, were examples of the forerunners of dogs, or canids, that Janis and the other researchers from Brown University based their findings on, according to an article in Forbes. As the environment became less icy and more open, pounce-pursuit predators became the norm. What they found was a change in the structure of the dogs’ elbows. The scientists measured the durability of fossil teeth by shooting light through the specimens and examining the different patterns of enamel.
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Janis explained, “The elbow is a really good proxy for what carnivores are doing with their forelimbs, which tells their entire locomotion repertoire”. It wouldn’t have made sense, they say, to evolve more cat-like physiology until the terrain allowed for such a strategy. The team a.so suggested that the presence of humans also may have altered the way the animals developed over time, but little research was done on that topic. Since carnivores once adapted to climate change in the past, it’s likely that they will continue to adapt as Earth continues to change.
