Monday, November 28, 2016

How Warming Is Threatening The Genetic Diversity of Species

The meltwater stonefly has adapted to a very specific and extreme niche — the cold, clear water that pours off of the melting ice and snow from the glaciers in Glacier National Park in Montana. This bug is on the leading edge of climate change because its frigid mountain habitat is rapidly disappearing. Since 1850, 85 percent of the ice in Glacier has disappeared, and all of it is forecast to vanish completely by 2020. In a study published this year, researchers found the cold-loving insect in trouble. “Their physiology requires really, really cold water, and they can’t survive once the water gets above an average of 9 degrees Centigrade during August,” said Joe Giersch, a biologist with the U.S. Geological Survey (USGS), who has studied this and a similar insect, the western glacier stonefly. Meltwater stoneflies and western glacier stoneflies move upstream to find cold water as things warm, and because of steeper mountain topography, populations become separated. This has interrupted gene flow, causing some genetics to disappear. As genes dwindle, the species is losing genetic variation and likely “adaptive capacity” — the genetics that give species the ability to evolve needed traits as habitat conditions change. It’s a big part of why the meltwater stonefly (Lednia tumana) is being considered for listing as threatened under the federal Endangered Species Act. And many of its fellow high-altitude insects are in trouble too. This stonefly, Giersch and his co-authors wrote, “likely represent a guild of species facing similar threats in alpine headwaters worldwide.”...more

 I've been worried and grieving over those high-altitude insects for quite awhile...

1 comment:

Anonymous said...

If the environmentalists want to slow down global warming let them keep their refrigerator doors open 24/7. Then at least they will not suffer in their own homes and they will be already acclimated as the world cools down.