Posted on 07/02/2009 4:12:57 PM PDT by NormsRevenge
PARIS (AFP) Climate change has caused a flock of wild sheep on a remote northern Scottish island to become smaller, according to an unusual investigation published on Thursday.
The study explains a mystery that has bedevilled scientists for the past two years.
The wild Soay sheep live on Hirta, in the St. Kilda archipelago in the storm-battered Outer Hebrides, and have been closely studied for nearly a quarter of a century.
The law of evolutionary theory says the brown, thick-coated ungulates should have got progressively bigger.
Tough winters mean that bigger sheep have a better chance of survival and of reproducing than smaller ones, and eventually they would dominate in the flock's numbers.
But in 2007, stunned researchers realised that the average size of the Hirta sheep, instead of rising, had been progressively falling.
The answer, British biologists said on Thursday, lies in climate change.
A team led by Tim Coulson, a professor at Imperial College London, pored over data for the animals' body size and life history over 24 years.
They found that the sheep were not growing as fast as they once did and smaller sheep were likelier to survive into adulthood instead of perishing as lambs.
This gives smaller sheep a shot at reproduction, which means that the average sheep size has fallen -- by 81 grammes per year (2.85 ounce) per year on average.
Coulson believes that shorter, milder winters mean that lambs do not need to put on as much weight in the first months of life in order to survive to their first birthday, as they did when winters were colder.
"In the past, only the big, healthy sheep and large lambs that had piled on weight in their first summer could survive the harsh winters on Hirta," he said.
Can it shrink a goiter too?
Ewe never know what baaaaaad science the global warming crowd is going to come up with next.
Breeding advantage favors larger males. Smaller animals can thrive on less food. Predation can introduce a number of factors, but is probably not important in this situation.
This sounds likes a situation where the food supply was impacted in some way. This could have been from a (sheep) population increase, reduced habitat, or just a more fragmented habitat (which could have been caused by something like an increase in fencing).
There are many possibilities.
Would this not be good news for those, who after legalizing gay marriage, would want to marry a sheep? I mean I wouldn’t know, but I’m just saying...
Would this not be good news for those, who after legalizing gay marriage, would want to marry a sheep? I mean I wouldn’t know, but I’m just saying...
At the same time a large size may be equally important ~ hence the large Columbians, the Neanderthals, the polar bears (a variation of the common brown bear that's able to survive in the far North), and various kinds of sealife.
This goes both ways ~ simultaneously. Ordinarily the "dwarfism" found in the far North will be described as "island dwarfism", but in many instances the affected creatures are not on islands - just land chopped up into small ranges by glaciers.
The wild Soay sheep that live on Hirta may simply be suffering from "island dwarfism", or "polar dwarfism", or maybe this is little more than a short rest between surges of polar gigantism.
We'll never know.
Mitch Daniels is certainly doomed.
Oh, no....Not the dreaded.....”shrinkage”
It must have been a tough place to live but the population at one time was maybe a couple of hundred or more which is a fair number for a small island.
Several migrations and a few diseases for which they had no immunity had reduced the number to around 28 when they finally left for the mainland.
Although they grew a few vegetable crops and had sheep and small cattle their diet consisted largely of birds and eggs of which the island had a lot.
It is now deserted except for a small military outpost.
Oops, can't have that now, must be global warming. Never mind that the earth hasn't warmed in the last decade. Now we not only have to defend global warming, but also evolution.
Shrinkage.....
If you watch the show “Smallville”, St. Kilda was the location of the Luther ancestral castle. Of course there never was a castle on such a remote, hard to get to place with only a handfull of people on it.
Also the song “Birks of St. Kilda” in the show was actually the tune of “Loch Lomond” and there was only grass on the island, no birks or birches as we call them.
The last 10 years have seen longer and harsher winters and they keep getting longer and harsher. How do they explain that? Actually, harsh, cold winters would cause smaller animals because the big ones require more food and therefore would die off quicker. These people are shameless and will say anything to promote global warming(some of them keep forgetting to use climate change).
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