A wide-ranging study appears to confirm what some scientists have suspected for a while: the world’s sixth mass extinction event is close at hand. What does this mean, and how can we save as many species as possible?
The research, which was carried out by teams from Stanford, Princeton and the Universidad Autónoma de México among others and is published in the journal Science Advances, saw researchers attempt to verify claims that many scientists have made that the Earth is about to enter or is already in fact undergoing its sixth mass extinction event. To do this, the researchers needed to find clear evidence that the extinction rate is substantially above what are considered normal baseline trends for species.
This is more difficult than it sounds because establishing that a species is extinct is actually quite difficult and itself requires robust data. However, the researchers used a recent and widely accepted estimate that suggests we should expect to lose mammal species at a rate of two mammal extinctions per 10,000 species every 100 years. They then compared that to the current rate of extinctions we’re seeing among mammal and vertebrate species, which as mentioned above is always a quite conservative figure.
The researchers found that based on this model the loss of species is profound. In fact, the researchers believe that, over the last century, the loss has been up to 114 times higher than general species die out would predict. Just to give an example of lost species (that is to say those that are functionally extinct in the wild), they include the Yangtze River Dolphin, the Caribbean Monk Seal, the Golden Toad, the Western Black Rhinoceros, and the Pinta Island Tortoise.
These estimates reveal an exceptionally rapid loss of biodiversity over the last few centuries, indicating that a sixth mass extinction is already under way. Averting a dramatic decay of biodiversity and the subsequent loss of ecosystem services is still possible through intensified conservation efforts, but that window of opportunity is rapidly closing.
The following video released by Stanford University explains this research in slightly more detail:
The researchers say that they have been deliberately conservative in their calculations to avoid being alarmist, but they believe that the numbers speak for themselves and the time has come to act before it is too late.
So what has caused this mass extinction? Unfortunately, as you may have heard in the video above, humans seem to play a large part. Our intensive farming and land clearing has damaged ecosystems and undermined others. Other causes can be attributed, at least in part, to our land grabbing as human populations sprawl and our tenements and infrastructure-building push out native species. We have also radically altered our environments and affected climate change at a rate that has left many species who cannot adapt highly vulnerable.
This could lead to population collapses at a rate that we have not seen before in our species history, and if that happens it could start a chain of collapse where whole ecosystems are lost. And, the researchers say, that could threaten human life too.
“If it is allowed to continue, life would take many millions of years to recover, and our species itself would likely disappear early on,” says lead author Gerardo Ceballos of the Universidad Autónoma de México in a release.
Can anything be done about this extinction event? Yes and we already know what that is: we need to take action on all of the environmental problems we’ve been grappling with for some years now: “Avoiding a true sixth mass extinction will require rapid, greatly intensified efforts to conserve already threatened species, and to alleviate pressures on their populations — notably habitat loss, over-exploitation for economic gain and climate change,” write the study’s authors.
This may mean some hard choices for conservation however.
For example, we have known for a long while now that the Giant Panda is all but functionally extinct, and new evidence emerges that its penchant for bamboo isn’t helping matters at all. Now, many say the Giant Panda must be saved and there are some good arguments for that, but other conservationists and, in particular, scientists have called on the wider movement to accept that some species are now past the point of helping–in the wild, that is–and that it would be better to channel our efforts toward keeping alive key species on which many ecosystems hinge, for example our pollinating insects, apex predators and key amphibians, so as to generate the most worth from our efforts. That doesn’t necessarily mean letting animals like the various endangered tiger species and elephant species die out, but it does mean taking an objective look at where our efforts can have the most pay off even as we work to try to undo the climate and environmental damage we have caused that has pushed the world to this point.
What seems clear though is that if we don’t get serious about the extinction threat, the extinction event could seriously threaten our futures, too.
Read more: http://www.care2.com/causes/the-sixth-great-mass-extinction-is-coming-how-do-we-stop-it.html#ixzz3dzdmELMc
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