Climate change is messing with nature’s biological clocks

Thanks to thousands of years of evolution, plants and animals have impeccable timing: flowers bloom, bears come out of hibernation, birds poke out of their shells at just the right time to find their places in the complex ecological web. But climate change changes the clock, and causes “phenological mismatches,” which means the timing is off. To hear some examples of these mismatches, the World’s Marco Werman speaks to Richard Primack, plant ecologist at Boston University.