World Biodiversity is Not Shrinking, It's "Turning Over"
Scientists are arguing that the biodiversity of the world's species has not been facing annihilation, it has simply been facing a change in whose on top.
For years and years we have heard that the world's incredible and diverse species are dying off faster than we can save them. In-part, this must be true. We see many species slowly disappearing as they are no longer fit for their environments. Even just last week scientists discovered a new species of Indian dancing frogs just as they approach extinction because of irreparable changes occurring to their natural habitat.
However, according to researchers, even as a great multitude of diverse species face terrible decline, an equally diverse number of species are lining up to take their place.
A study published in the peer-reviewed journal Science details how the world's species are actually simply undergoing a massive "turnover."
To determine this, researchers carefully selected 100 studies that contained a total of six million observations on more than 35,000 different species. The majority of the studies made observations on species and variety change over the last 40 years, but some stretched back as far as 1874, according to a University of Vermont press release.
The researchers predicted that they would find a drop in variety of species, even if the numbers were being filled in by the aggressive expansion competitors. However, this was not the case.
Instead, they just saw change. Nearly 80 percent of the regions the team examined showed substantial changes in species composition - changing about 10 percent per decade - but not resulting in any declines in total population or variety.
Nick Gotelli, an ecologist from the University of Vermont (UVM) and member of the study's research team explained that diversity may not drop because even as habitats change, they become available for some other new species.
"We move species around," Gotelli said in a statement. "There is a huge ant diversity in Florida, and about 30 percent of the ant species are non-natives. They have been accidentally introduced, mostly from the Old World tropics, and they are now a part of the local assemblage."
According to Gotelli, the study's results don't mean to claim that harm isn't being done to the world through pollution and climate change. They simply show that measuring this harm and change through numbers or diversity-per-region alone is not enough. Mother nature will always adapt.
"Right under our noses, in the same place that a team might have looked a decade earlier, or even just a year earlier, a new assemblage of plants and animals may be taking hold," Gotelli said.
The study was published in Science on April 18.
The UVM press release was published on May 7.