The cause? Human activities, such as the destruction of habitats for crops or infrastructure, as well as overfishing, hunting and so on.
The extinction crisis is as bad as the climate change crisis. It is not recognized
The study is unique because instead of merely examining the loss of a species, it examines the extinction of entire genera.
In the classification of living beings, the genus lies between the rank of species and that of family. For example, dogs are a species belonging to the genus canis -- itself in the canid family.
The researchers relied largely on species listed as extinct by the International Union for Conservation of Nature (IUCN). They focused on vertebrate species (excluding fish), for which more data are available.
most of them in the last two centuries.
"If you take one brick, the wall won't collapse, he said. "You take many more, eventually the wall will collapse. "Our worry is that ... we're losing things so fast, that for us it signals the collapse of civilization."
All experts agree that the current rate of extinction is alarming -- but whether this represents the start of a sixth mass extinction (the last being the asteroid that wiped out the dinosaurs 66 million years ago) remains a matter of debate.
broadly define a mass extinction as the loss of 75 percent of species over a short period of time. Using that "arbitrary" definition, Cowie said, a sixth mass extinction has not yet occurred.
But if we assume that "species will continue to go extinct at the current rate (or faster), then it will happen," he warned. "We can surely say that this is the beginning of a potential sixth mass extinction."
Glasp is a social web highlighter that people can highlight and organize quotes and thoughts from the web, and access other like-minded people’s learning.