Lemuroid ringtail possums like this one are at risk of extinction from global warming.
Courtesy Mike Trenerry/Wet Tropics Management Authority
Lost: Old Trees
Yosemite National Park lost a quarter of its large trees over the past 60 years, according to a recent study that analyzed the park’s meticulous records. Ecologists suspect warmer temperatures have cut the trees’ water supply and that the trend could be just as bad around the world. Old trees survive forest fires and infection better than younger ones, and thus are critical for maintaining ecosystem health.