Fraggle Rocker
Staff member
I don't think this is any more true than the average absolute statement. They keep finding populations of animals that have been separated by catastrophe or human settlements whose DNA appears to have descended from a single pair. I remember reading about a colony of big cats several years ago, possibly cheetahs, that were like that.Alpha said:
The problem with inbreeding is that you occasionally double up recessive genes that create unhealthy individuals. That's a huge problem for human royal families, who go to great lengths to keep the unhealthy individuals alive and then deliberately breed them. It's obviously less of a problem in species where the weak will be allowed to die, possibly even eaten by their own kind, and at least never find a mate. The weak genes have a good chance of being selected out before they take over the whole population by chance.
It's even easier with captive breeding. You don't allow the animals to choose their own mates so you control the development of the gene pool.
Pet breeders do it all the time. If they find a trait they like they breed the family members together like crazy. The hard-hearted ones let the weak die, the softies just get them neutered so they're out of the gene pool. The scrupulous ones do this for many generations before they start distributing them outside the kennel community.
The matron of our "virtual kennel" of Lhasa Apso breeders was trying to get longer legs by inbreeding and this one puppy really had them. Unfortunately not only were they a bit too long, but the front legs are noticeably longer than the rear. And his jaw has an overbite worse than Homer Simpson. And his head is shaped like a fox. And his tail is curled so tight it looks like a pig. But after a little dental surgery there was nothing else wrong with him. We owed her a favor so we took him in and diligently neutered him and he's just the sweetest dog in our pack. And very athletic with those long legs.
Many breeds of dogs and cats began that way. Somebody either by mutation, accident or inbreeding got a male and a female in the same litter with the characteristics they wanted, so they bred them to each other. Nowhere else to go for a mate, after all. Himalayan cats, probably also Somalis. Surely the Pharaoh hound -- turns out it just looks like the dog in the ancient Egyptian carvings, DNA shows somebody recreated it about 150 years ago by carefully crossbreeding various other sighthounds.
We've got a blue-eyed Lhasa Apso but the damn breeder quietly gave his sisters away because he knew the AKC wouldn't register them. If we could have gotten one we'd be working on our fourth generation of true-breeding blue eyed ones. AKC be damned, he's gorgeous and we'd have no trouble finding people who wanted one once we got the kinks out of the gene pool.
What's this new stuff about Lucy? When the DNA discovery was first made they were trumpeting the "fact" that we're all descended from a single woman. Has this been disproven?