1
3

[–] ChristoDeFetus 1 point 3 points (+4|-1) ago 

They don't know not to. That's one of the problems in trying to preserve critically endangered species. You gotta relocate horny dudes to create viable offspring.

1
0

[–] AnmanIndustries 1 point 0 points (+1|-1) ago 

Someone already said it. They dont know. There are a group of animals that DO know, such as some birds, but for the most part they dont. In live stock and I would imagine in the wild, father/mother to child is actually ok and the genetics are diverse enough to not cause any problems. Sibling to sibling is crossing the line. We have to remove the young males from all new births for our animals, pigs, sheep, rabbits and birds. Although, we mainly do it with the birds because they the older males usually attack the younger ones. Genetics with birds is even more forgiving.

0
0

[–] littul_kitton ago 

Genetic diversity does not help at all. If the species has 200 broken genes per individual, then father-daughter mating produces offspring who average 50 genes with both copies nonfunctional. That's 50 simultaneous severe generic diseases per offspring. You know those weird-looking retards who have a single genetic disease? Imagine an individual with 50 such diseases at the same time. That's inbreeding for you.

A species either has to avoid this, or has to have so many offspring that it doesn't matter. There is a good chance that the lower animals have such a good sense of smell because it helps them avoid incest.

0
0

[–] AnmanIndustries ago 

With small to medium sized live stock we do not bother with this as long as we are able to breed in the genes that we do want. That being said, over time we always introduce new genes. You are right though, we would never breed parent to child indefinitely. Id do sheep maybe 2-3 times, rabbits twice the amount and I dont keep parent birds long enough to really know when I should stop.

A lot of animals genes normalise out in the wild into a mix of average. Like mixing all the different colours into brown. I know this happens to horses and rabbits predominantly.

2
-1

[–] SpectralForces 2 points -1 points (+1|-2) ago 

Pheromones I suspect. Humans are no different in that regard.