Elephants are important. What about rhinos? Are you talking about lions? If the last large animals are lost, what will happen? Professor of Biology Felisa Smith at the University of New Mexico studied the impact of the loss of megafauna on the environment.
Smith and her team have just published a paper, "Late Pleistocene megafauna extinction leads to missing pieces of ecological space in a North American mammal community." Smith and her team looked at the past to find clues about the future of large mammals, which are declining at a rapid rate.
Large-bodied mammals are in dire need of protection. Their decline has consequences that are unique to them. This type of loss is not new. Smith said that humans entering the Americas around 13,000 years ago caused a widespread extinction of large-bodied mammals then through some of the same activities that endanger mammals today. The fossil record of this earlier extinction shows what happened to the surviving mammals.
The team looked at thousands of fossils at the Texas Memorial Museum in Austin, Texas, which were from the mammal community in Texas. They were able to estimate body size with the help of stable isotopes in fossil bones. After the extinction, they were able to reconstruct the ancient food web.
The community was reorganized after the extinction and there were many vacant niches. The co-author of the paper said that the loss of complexity probably meant a reduction in the resilience of the environment.
The results were striking for the felid guild, which had included two species of saber tooth cats.
After the large cats went extinct, the jaguar became the top predator and shifted its diet to focus on bison, a niche previously filled by the extinct cats. Due to competition, mountain lions who had previously been absent became common.
"We don't see much of a change in the diet of the canids," he said. The wolves, coyotes, and foxes all stayed in the same area. It shows how flexible they are.
The decline of elephants, giraffes, rhinos, and other large-bodied mammals has serious consequences for the environment because of their important functional roles, as well as the structure and composition of plants and biogeochemical cycles.
Smaller mammals don't play the same role as larger mammals. Understanding how the decline or potential extinction of Earth's last remaining large-bodied mammals might change the environment is critically important. We cannot afford to lose these mammals.
"Our research of ancient mammals highlights what might happen if Earth's remaining large-bodied mammals go extinct– animals such as elephants, rhinos, zebra, and lions, and it demonstrates how insights from the past can really inform modern conservancies."
More information: Felisa A. Smith et al, Late Pleistocene megafauna extinction leads to missing pieces of ecological space in a North American mammal community, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2115015119 Journal information: Proceedings of the National Academy of Sciences
All Rights Reserved © 2024
