The decline of mammals for 130,000 years plunges the entire food chain

Food chains are collapsing, as “more than 50% of the links in the mammalian food web have disappeared”. The phenomenon is accompanied, according to a study, by a loss of ecosystem resilience. Only a few species would be enough to make their stability disappear.

The food chains crumble and break. In question, the disappearance caused by Man of numerous species who played a key role. This is explained by a study published in Sciencein which researchers studied the evolution of food webs worldwide over 130,000 years. These correspond to the assembly of multiple food chains that form a network of prey-predator interactions.

“This approach can tell us who is eating who today with 90% accuracy.explains Lydia Beaudrot, first author of the study and ecologist. This is better than previous approaches have been able to do, and it has allowed us to model predator-prey interactions for extinct species.”

For their research, the team used algorithms frommachine learning based on documentations of prey-predator interactions and traits of each animal. The established model then allowed the simulation on a global scale of “who ate who” for 130,000 years.

Food webs are collapsing, but all is not lost

By mapping this evolution of food webs over time, scientists have realized an alarming fact: they are declining. “While about 6% of mammals terrestrial animals disappeared during this period, we estimate that more than 50% of mammalian food web links disappearedworries Evan Fricke, co-author of the study and ecologist. And which mammals are most likely to decline, both in the past and now, is key to the complexity of the mammalian food web.”

But, according to them, all is not lost. Because it’s not just the extinctions that have caused the decline of food webs: the geographical distribution of species has also changed. “The restoration of these species to their range history offers great potential to reverse these declines”says Evan Fricke.