Wildlife ecologists have seen white-tailed deer expanding their range in North America over many decades. And since the early-2000s these deer have moved north into the boreal forests of western Canada. These forests are full of spruce and pine trees, sandy soil and freezing winters with lots of snow. They can be a harsh winter wonderland. And ecologists haven't known whether a warmer climate in these forests or human land development might be driving the deer north. A recent study tries to disentangle these factors – and finds that a warming climate seems to play the most significant role in the movement of deer.

Read more in the journal Global Change Biology.

Curious about more wildlife news? Email us at shortwave@npr.org.

Nuclear fusion could one day change the world by producing energy at lower costs than we generate it now — without greenhouse gas emissions or long-term nuclear waste.

If we can get it to work.

People have been promising nuclear fusion as a new, clean source of power for decades without much tangible success. But lately, billions of dollars from venture capitalists and tech entrepreneurs have flowed into the field. Science correspondent Geoff Brumfiel shares his reporting on some of the companies racing towards what could be the world's first commercial fusion power plants.