As the planet’s average temperature rises (due in part to humanity’s influence), plant and animal species make their way towards the poles at an average of 3.8 miles per decade. That can work for some species in places like North America and Europe, where most of this sort of research is conducted, but populations relying on unique climate ranges in Australia, South America and New Zealand will have no such luck. As a result, a researcher from the University of Connecticut says that we’re at risk of losing one in six species alive today, and possibly more.
“We can look across all the studies and use the wisdom of many scientists,” says UConn ecology and evolutionary biology professor Mark Urban. “When we put it all together we can account for the uncertainty in each approach, and look for common patterns and understand how the moderators in each type of study affect outcomes.”
Even here in North America, some species are already at risk. The American pika, a sort of hamster-ish animal, is already disappearing from the southern regions of its mountain habitat. Whereas some mountain species can climb higher or migrate northward to escape rising temperatures, the pikas already live at such high altitudes that there isn’t anywhere for them to go.
Urban’s meta analysis predicts a 3% extinction rate under current circumstances. If the earth warms another 3 degrees Celsius, the extinction risk rises to 8.5%. If climate change manages to continue on that trajectory, the world would experience a 4.3 degree rise in temperature by the year 2100. That equates to an extinction rate of 16%, or about one in six.
Though 60% of studies on the subject have examined the effects of climate change in Europe and North America, Urban says its species in South America, Australia and New Zealand that face the greatest risk. Those species either already live closer to the poles and have nowhere to go, or rely on unique temperature and rainfall levels to survive. A species of frog called the nursery frog, for example, lives only in Queensland, Australia’s Wet Tropics region. Given Australia’s isolation, that species would be unable to colonize elsewhere should climate change affect rainfall levels.
Among Urban’s findings was the realization that all species were more or less at equal risk for extinction, with no trends developing by taxonomic group. That, he says, just further cements our responsibility to fight climate change.
It’s hard enough to predict change, but in the end, we have one climate to contend with,” says Urban. “With living things, we are dealing with millions of species, none of which act precisely the same. In fact, we may be surprised, as indirect biologic risks that are not even recognized at present may turn out to have a greater impact than we’ve ever anticipated.”