Numerous studies and researchers have confirmed the rapid extinction of many species on the earth, including mammals, amphibians and 'big cats.' A new study, conducted by a team at the University of California, Berkeley, has put forth a new theory - the absence of newly emerging evolved species may also contribute to the extinction of the existing ones.
"Virtually no biologist thinks about the failure to originate as being a major factor in the long term causes of extinction," co-author of the report and the director of the UC Berkeley Museum of Paleontology and a professor of integrative biology, Charles Marshall, explained. "But we found that a decrease in the origin of new species is just as important as increased extinction rate in driving mammals to extinction."
Though these effects would be more prominently observed following a period of millions of years, these findings may help biologists better understand how the animal and plant life today are under huge stress, and what could be the possible reason behind the extinction of species in the past.
Their study took in an earlier research that involved 19 groups of mammals that were either completely extinct, or on the verge of extinction. They also included the analysis of fossil records based from thousands of years ago.
The study was actually meant to understand if what the Red Queen hypothesis (a presumption by Lewis Caroll in his book Through the Looking-Glass that animals must continually evolve to avoid extinction) was actually true.
Through their findings, the researchers confirmed that the rapid extinction of mammal and other species isn't just dumb luck; there are actually a lot of reasons involved, including a deteriorating environment, competition, predators and the need for constant evolution.
"Each group has either lost, or is losing, to an increasingly difficult environment," Marshall added. "These groups' demise was at least in part due to loss to the Red Queen - that is, a failure to keep pace with a deteriorating environment."
They also found that some animal groups reproduced and increased their numbers to the highest capacity the environment could take, and when the environment started deteriorating, their numbers started decreasing rapidly, leading to their extinction. "In fact, our data suggest that biological systems may never be in equilibrium at all, with groups expanding and contracting under persistent and rather, geologically speaking, rapid change," Marshall concluded.