This story appears in the November 2015 issue of National Geographic magazine.
Climates change. That’s a fact of nature. But Earth’s climate today is changing so dramatically that it’s transforming land and sea, affecting all forms of life.
“There will always be a minority that manage to thrive in relatively sudden new conditions,” says Thomas Lovejoy, a George Mason University conservation biologist and a National Geographic fellow. “But the vast majority will be terribly battered,” if not crushed.
Higher temperatures caused by greenhouse gases are just the beginning of this ride. Next come extreme weather (including extensive drought), shifting breeding and migration seasons, and changing food availability, new disease patterns, rapid ice melt, and rising seas. Each change begets a host of others: Effects run far and wide.
Change can be good for some—a longer spring with more food, a comfortable niche to call home, a stressful migration avoided. But as the layers build and warming continues, winners may hit new limits and lose their edge.
This isn’t the stuff of the future. The effects of an altered climate are evident now.
“There’s no going back,” says the University of Queensland’s James Watson, who directs the Global Climate Change Program of the Wildlife Conservation Society. “Everything is changing.” Wildlife that’s enjoyed a relatively stable climate for the past 10,000 years is being pushed and tested like never before.
And our predictions of “winners” and “losers” haven’t always been spot-on, he says: “We’ve rarely gotten right how bad it will be. The degree of melting at the Poles and its ripple effects [on wildlife] have been staggering,” for example. The sensitivity of many coral ecosystems to temperature and storms is another. “There’s a lot to grapple with.”
But experience and models and what we know of biology can give us a solid near-term picture. What species adapt well to rapid change? Generalists that tolerate a range of climates. Those with diverse genes and speedy reproduction (which lets helpful traits enter the gene pool fast). Those that can travel to a suitable new habitat—and that have somewhere to go. Competitive, often invasive species. Weeds.
Which do poorly? Specialists with narrow climate needs. Those already battling for survival. Small and fragmented populations, or those hemmed in by unsupportive landscapes. Animals competing with humans. Groups lacking genetic diversity. High-elevation species, island dwellers, and many coral-dependent animals. Those needing ice to survive.
We can’t stop this train. But we can slow its destructive run. Restoring landscapes should be a big part of the game plan, says National Geographic Fellow Lovejoy, who adds that longtime degradation of ecosystems has created a lot of the excess carbon dioxide. “A massive restoration effort could actually remove half a degree worth of potential climate change from the atmosphere before it happens.”
Heading off more damage and caring for what’s left must be dual priorities. “The best we can do now,” says the Wildlife Conservation Society’s Watson, is to identify and protect key populations, “then try to stop humanity from getting in the way of their functioning.”
Joel Sartore founded the National Geographic Photo Ark in an effort to slow, or stop, the world’s extinction crisis. Learn more about the project at natgeophotoark.org.