Scientists solve mystery of Scotland's shrinking sheep

[Al-khiyal]

Scientists solve mystery of Scotland's shrinking sheep

July 3, 2009 -- The mysterious shrinking sheep of St Kilda sounds like a job for super-sleuth Sherlock Holmes. The case involves a rare herd of wild sheep on the remote Scottish island - known in Scottish Gaelic as Hirta - that are refusing to bow to conventional evolutionary pressure, which says big is best. Instead, they have steadily decreased in size since the 1980s.

Scientists have now stepped in to solve the conundrum, and fingered the culprit as the new Moriarty of mankind: global warming. The experts say shorter and milder winters mean that lambs do not need to put as much weight on during their first few months of life. Smaller animals that would have perished in harsh winters a few decades ago can now survive to their first birthday. As a result, the average weight of the sheep has dropped by 81g each year.

The difference is too small to see with the naked eye, but it is important because it shows how animal populations can respond to climate change. Tim Coulson, a biologist at Imperial College London who worked on the study, said: "If animals can respond [to climate change] and can respond fairly rapidly, then evolution could play a role in helping them to adapt." The results appear in the journal Science.

Biologists have reported that several species of birds and fish are changing size and shape, which could be down to global warming. Coulson said it was difficult to say what the response of the St Kilda sheep could mean for other species. Their island home, St Kilda, is just "vegetation and sheep" he said. In other cases, predators and competition for food from other animals complicate the picture and make it difficult to tease out the influence of changing climate.

The study looked at a herd of wild Soay sheep on Hirta that biologists have studied since 1985. Dogs are forbidden on the island, so the scientists acted as human sheepdogs to herd the animals, which are expert jumpers, towards areas where they could be weighed. "These aren't fluffy white sheep, these are small and brown and wild animals," Coulson said.

[amalgamate]

subhanallah, the effects of global warming will slowly diminish all species into oblivion!



jk

[Bent_Bladi]

so global warming will make us all lose weight... interesting

jk um hi