New research explains why surviving lemur species may be in a downward spiral of ecological retreat
New research suggests that the disappearance of one species does not necessarily mean that the remaining competitor species will be able to thrive by filling the empty niches left.
The University of Cincinnati-led research published in the Proceedings of the Royal Society B (by lead author Brooke Crowley) comes to the conclusion that one likely result of changes that lead to species’ extinctions is that remaining species go into “ecological retreat” which can bring about new selective and ecological pressures. This in turn can increase the extinction risk of surviving species even to the possible extreme of generating an “extinction cascade.”
Radiocarbon and isotope analysis from lemur fossils helped to determine the type of habitat in which lemurs used to live as well as their diets, when they died out and whether other still-extant species filled vacated environmental niches.
“The reasons behind the increased reliance on densely forested habitats are uncertain, but it’s likely that low hunting and logging pressures in forest reserves are contributing factors,” explained Professor Crowley.
Since lemur species used to inhabit both drier more open areas as well as dense forests, they are not specifically adapted yet to just inhabiting forest, which puts them at a disadvantage.
“It’s been assumed that lemurs were in the forests because that’s where the resources that best suited them were. Our fossil analysis shows that lemur species once preferred a much wider, more distinctive habitat range, which may mean that modern lemurs prefer the densely forested areas simply because these areas offer greater protection. The forest is more of a refuge,” says Crowley.
Source: Science Daily