Weird Ways Global Warming is Changing Animal Populations


Fishing could become a pastime of the past if global temperatures continue to rise, according to a recent study. Photo courtesy of Wayne National Forest, via Flickr.

We all know global warming is generally changing the planet for the worse, but the specifics aren't always on our minds.

You'd have to be living under a rock not to know glaciers and ice caps are melting, and water levels are rising, but did you know trees are dying, and the Arctic Sea floor is releasing methane? And what about shrinking sheep? Scientists are discovering the varied ways warmer temperatures are changing the planet's ecosystems, and three recent studies shine a light on the complex ways rising temperatures are changing (or will change) wildlife population levels.The Incredible Shrinking Sheep Mystery
Researchers in London believe the decline in average body weight of Scotland's Soay sheep can be attributed to shorter winters --for which the blame falls squarely on global warming.

The size of the wild breed, which lives on the island Hirta in the St Kilda archipelago, has progressively dropped over the past two decades despite the fact that natural selection should have the reverse effect. So researcher Timothy Coulton adapted a natural selection model to include an environment variable and discovered that smaller sheep, which would normally not have made it through previously longer winters, were surviving.

Mystery solved. But what about the effect of an increasing sheep population on the island's ecosystem? Somehow, I don't think this is altogether a good thing.

No More "Gone Fishing" Days?
Do you whittle away summer days fishing? Good luck, if climate change continues to accelerate. A new study shows warmer temperatures will kick off a chain reaction in lakes that will cause a dramatic drop in fish.

Warmer temperatures, thawing of permafrost and changes in precipitation are expected to cause more colored organic matter to run off into lakes, turning the water brown. Brown water keeps the sunlight from reaching the bottom of the lake. Algae at the bottom of the lake can't survive without sunlight. The organisms that eat algae won't have enough to eat and many will die. The fish that eat those organisms won't have enough to eat and they too will die. So, fewer fish are the end result.

Cockroaches Breathe Easy
It should come as no surprise, but scientists have discovered cockroaches are equipped to deal with global warming. What's the creepy-crawly insect's secret weapon?

Cockroaches can live without breathing for up to 40 minutes. Since roaches lose water as they breathe, holding their breath would allow them to survive in increasingly dry climates. So even as humans are driven out of drought-plagued areas, roaches will continue to thrive.

More On Endangered Animals and Changes From Global Warming
The Frogs Still Need Your Help!
Seven Endangered Species Rulings to be Revised
7 Endangered Animals Cute Enough for Celebrities to Save

Tags: Animals | Biology | Drought | Fish | Global Climate Change | Global Warming Effects | Insects | Scotland

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