The Heat Is On: Evolution in Action

PRODUCERS: Adam Burke

Climate change has always acted as an evolutionary force on the planet. Some researchers even believe that adaptation to pre-historic climate change may have lead to the success of human beings as a species. So what's different about the changes happening now?

Extinction is more ordinary than we think. We're all just species clinging to the edge of a life raft, and climate change has always been one of the major drivers behind evolutionary change.

In the age of rising global temperatures, this episode of The DNA Files raises the curtain on the opera of extinction and survival—looking at who wins and who loses under the shifting fortunes of climate change.

Does Climate Change = Genetic Change?

This is a program about the power and limits of adaptation, and what climate warming means for life on earth. How are plants and animals responding to climate change now? What information can we glean about climate change from the trail of paleo-historical breadcrumbs left behind from past warming cycles? What does genomic and genetic research offer us as we look toward a warmer future?

Host John Hockenberry and producer Adam Burke invite listeners to consider these climate change questions through the lens of evolutionary baseball. Some species seem to be able to hit the climate change pitch, while others are up at bat with two strikes.

We begin with a visit to the lab of Christina Holzapfel and William Bradshaw, researchers at the University of Oregon. They specialize in a tiny insect—the pitcher plant mosquito. A few years ago they realized they had data showing that these insects were genetically adapting to climate change to take advantage of warmer days. Emerging science shows that other insects, animals and plants are also genetically evolving to adapt to warming trends, while others are either on the move to find a new sweet spot or find themselves trapped in ecological niches.

Climate Change in Australia

Climatic ebbing and flowing has left its fingerprints on the genes of species native to the Australian wet tropics. We meet Stephen Williams and Craig Moritz, researchers who use paleo-mapping and population genetics to understand what happened in this sensitive bio-region in pre-history during periods that were warmer and dryer.

We travel deep inside the Australian jungle to find out what is living there. We learn what the past says about how those creatures were affected by warming and cooling trends. Moritz and Williams believe information like this will be essential in anticipating ecological areas and species most at risk to increased warming now.

We move from the tropics to Australia's Great Barrier Reef. When it comes to climate change, coral reefs are among the most brittle, stressed, at-risk ecosystems. Scientists, though, disagree about what is happening to coral and what it means. Researcher Morgan Pratchett tells us that as the oceans grow warmer, the coral begin to die off and the complex ecosystems they support die off, too. Terry Hughes, the director of the ARC Center for Marine Excellence at Australia's James Cook University, thinks coral reefs may be able to survive a certain amount of warming.

But survival at what cost? Ove Hoegh-Guldberg, a coral scientist at the University of Queensland, in Australia (also associated with ARC), says even if coral reefs and their ecosystems do survive warming trends, they will survive on a much more limited scale, supporting a much different set of species than they do today.

Can We Keep Up with Climate Change?

Which bring us to the effect of climate change on humans. Prehistoric climate change forced humans to move across continents and to create new technologies. Anthropologist Rick Potts says that adaptation to waves of successive climate change gave rise to the success of the generalists—the cockroaches, the crows, and us. The question now is whether we'll be able to keep up with the pace of rapid climate change engendered by our success as a species.