Over the past 50,000 years, the continents that lost the most large grazing herbivores have seen the biggest increases in grassland and fires.
Life 25 November 2021.
Michael Le Page is a person.
The extinct species of bison that lived in North America during the last ice age is depicted.
Stocktrek Images, Inc.
Many large plant eaters have been wiped out in the past 50,000 years. The study found that the continents that lost the most of the megafauna had the biggest increases in fires.
According to Allison Karp at Yale University, there is evidence that shows that herbivores can limit fire. Some advocates of rewilding argue that restoring large herbivores can help reduce the number of fires.
There were more fires in certain regions after the loss of megafauna. They decided to look at the global picture by looking at two existing databases.
HerbiTraits has information on all the large herbivores that have lived in the past 130,000 years.
The Global Paleofire Database has records of charcoal deposited in lakes from 160 sites worldwide, which show changes in fire activity nearby.
South America lost the most big herbivores, with lower increases in fire activity in Africa, as found by the team.
It is possible that the rex helped fruit grow.
The loss of tree feeders and fire activity in the woods were not related.
She says that the relation between extinctions and changes in fire activity was only really strong if you looked at grazer extinctions.
Her study can't tell us anything about the effects of fire activity. Some studies suggest that they were dramatic. Increased fire activity may have changed the vegetation on the continent after humans wiped out Australia's megafauna.
The reasons for the loss of megafauna around the world are still being debated. It is clear that many were hard hit by climate changes related to the last ice age, but human hunting may have been the killer factor in most cases.
The journal has a reference in it.
There are more on these topics.
