Computer models revealed how the extinction of large megafauna such as mammoths and saber toothed cats may have significantly changed the way species interacted after the end of the most recent ice age 11,000 years ago.
The recent study is the first to look out how major extinctions influenced the distribution and interaction of the carnivorous species that remained during the Pleistocene, the University of New Mexico reported.
"Whatever the cause of the extinction, humans or climate, we are certain that the disappearance of millions of large mammals resulted in major ecosystem changes," said Melissa Pardi, a doctoral candidate and paleontologist at the University of New Mexico. "What we're trying to do is figure out what those changes were."
The research focuses on canids, including wolves and domestic dogs. These species are important because they interacted with post-ice age animals, but are still alive today. The researchers hoped to gain insight into how these canids responded to the extinction of other major hunters.
"It's tricky to predict," Pardi said. "On the one hand, competition may have decreased. On the other hand, many prey species also went extinct and humans, which were probably hunting similar things, would have also been a significant challenge to contend with."
To make their findings, the researchers looked at the fossil record of several canid species from the past 20,000 years, and built computer models to see which species roamed the same territories following the extinctions of other large carnivores. An increased overlap suggested the species were generally able to inhabit the same areas, while a decreased overlap suggested they were incompatible. They found canid species typically avoided each other after the Pleistocene extinction.
"After the extinction interactions between canids changed dramatically, and not always in the directions we would have predicted. The influx of a novel predator, humans and their dogs, also seems to have impacted distributions," said Felisa Smith, a professor of Biology also at UNM.
The scientists hope their research will help influence conservation efforts looking towards the future of species preservation.
"When we see extinctions in modern ecosystems, we tend to only consider the individual species that go extinct," Pardi said. "What we often don't see are the changes in interactions throughout the rest of the community. We don't just lose species, we lose those connections."
The findings were published in a recent edition of the journal Ecography.
