Sunday, May 03, 2009

Ancient selective breeding reveals intelligent design?


The headline for an article in New Science really caught my eye - "Ancient Breeders Show Intelligent Design". With all of the excitement over the 200th anniversary of the publication of the "Origin of Species" and after watching a program on PBS about the recent legal battle between proponents of Intelligent Design and biology teachers in New Jersey, I couldn't help but do a double take, fearing a political coup at the headquarters of this online scholarly publication. As it turns out it was just a writer's effort to garner attention, as the piece was quite scientific.

Researchers have shown that, in the case of horses, DNA evidence points to coat coloration manipulation through breeding practices after the horse was domesticated about 5500 years ago. The study involved 89 equine fossils ranging in age from 42,000 years ago to medieval times and in location from Spain to China.

A similar study of ancient sheep fossils by researchers at the University of Glasgow showed that ancient sheepherders in Iraq and Iran began selecting sheep who shed their coats less often and developed shorter horns about 6,000 years ago.

When I was in high school my science project focused on genetic coloration in mice so I always find this kind of thing fascinating.

[Image: The Gute sheep originate from the horned sheep that have been kept in open pasture on the island of Gotland from ancient times. The population was almost extinct in the beginning of the 1940´s, after which the remaining horned sheep were collected and the flock started to increase in numbers. The sheep are hardy and well adapted to the island climate. Traditional use is for production of both meat and wool. The colour varies from light grey to nearly black. Both the rams and ewes are horned with short tails. The wool is double coated with underwool and guard hair and is mostly used for making carpets and souvenirs. The average live weight of rams is 75 kg and of ewes 50 kg. The mean litter size is 1.4 lambs at birth. The present population size is around 5,500 sheep and is increasing (year 2000).
See also Breeds of Livestock, sheep breeds.

Local name: Gutefår
References:
Sven Jeppsson, Jordbruksverket, 551 82, Jönköping, Sweden.
Photographs:
Jordbruksverket, 551 82, Jönköping, Sweden.

Courtesy of North Shed website]