Click the link to read the article on the National Public Radio website (Jonathan Lambert). Here’s an excerpt:
To consider how climate change could cause some extinctions, imagine a tiny mountain bird that eats the berries of a particular mountain tree. That tree can only grow at a specific elevation around the mountain, where it’s evolved over millennia to thrive in that microclimate. As global temperatures rise, both the tree and the bird will be forced to rise too, tracking their microclimate as it moves uphill. But they can only go so far.
“Eventually, they reach the peak, and then there’s nowhere else to go,” says Mark Urban, a biologist at the University of Connecticut.
Scientists call this mountain phenomenon the “escalator to extinction” and it’s just one way climate change is already squeezing plants and animals from their habitats. Researchers have conducted hundreds of studies projecting how different species might respond to different levels of climate change, finding varied results. In an analysis published Thursday in the journal Science, Urban sought to bring all those studies together…If countries meet the shared goal of limiting warming to 1.5 degrees Celsius, 1.8% of species will be at risk of extinction by the end of the century, Urban reports. But if global warming gets out of hand, warming four or five degrees Celsius, as many as 30% of species could be at risk…He points to confounding complexities in how species might respond to such climate extremes that scientists don’t yet know. More critters may simply not be able to cope, or ecosystems that lose species after species may collapse altogether. Additionally, many rare species are understudied, or not even discovered, and might be especially vulnerable in ways that don’t show up in this analysis…Different species face some different risks. Amphibians, including frogs and salamanders, are more vulnerable, Urban found, perhaps because their habitats are more sensitive to environmental changes. Species that live on islands, mountains and in freshwater could face more challenges, too. Targeted conservation efforts could help slow losses, Urban says, but they’re ultimately no substitute for reducing emissions.