UCSB Researcher Examines ‘Sixth Extinction Wave’
The phrase “sixth extinction wave” alone is quite frightening. But its destructive implications on species populations could be much worse. The brutal consequences of what is dubbed Anthropocene defaunation, or the “recent pulse of animal loss,” was the focus of an article published in Science last week. UCSB researcher Hillary Young contributed to the report, which called for action to mitigate animal overexploitation and land-use change in order to buy time to address anthropogenic climate disruption.
“It is pretty grim,” said Young, who has spent her career studying what it means for humans when communities disassemble. “I think a lot of the reason we tried to write this paper was an alarm call.”
According to the study, overexploitation and human destruction of habitat are the key drivers of wildlife population decline and extinction. Notably, the study notes Anthropogenic Climate Disruption will likely soon go head-to-head with habitat loss as the most important driver of defaunation, or a decline of an ecosystem from human impact.
The article in Science runs through a number of startling statistics. Of the roughly 5 to 9 million species on the planet, the report states Earth is likely losing 11,000 to 58,000 species each year. And this does not even reflect “local extinction” — species dying off in a certain area — or declines in species population sizes. Further, between 16 and 33 percent of all species are globally threatened or endangered. (Debate about exactly when humans started to impact ecosystems around the globe still exists, the article notes.)
The article also discusses invertebrate biodiversity — worms and insects — which receives considerably less attention in the conservation realm. “We motivate conservation by putting panda bears on our products,” Young explained. “Those are creatures people want to know what is happening to. But they are often pretty low density creatures, and they don’t drive ecosystems that drive and change pollination.” Insect pollination, on the other hand, contributes to 10 percent of the world’s food supply. And pollinators appear to be disappearing in both abundance and diversity, the study states, which have been linked to steep declines in relative abundance of plant species reliant on those pollinators.
So what does Young do to stay upbeat and do her part to mitigate widespread disaster? “We can all try to drive our hybrid cars and address carbon dioxide emission…. Don’t buy animal products when you don’t have to,” she said. “And eat lower on the food chain.” Overconsumption is probably the biggest issue, she added. Though it’s such a large scale problem, anything you can do to affect those drivers will help, Young said.
