One article is 20 yrs old by someone named Christopher..with unprofessional venting against inbreeding apologist.
The other quite good.
Inbreeding avoidance behavior can be a boon to the long-term survival of a species.
But it can also be a great hindrance.
With this amount of inbreeding avoidance, the authors looked at computer models to see how long it would take such a population to become extinct solely upon the basis of its inbreeding avoidance behavior. Populations that avoided incestuous breedings between a parent and siblings and between siblings were estimated to become extinct in 63 years. Those that avoided mating with second order relatives were estimated to become extinct within 37 years, and those that avoided third order relatives were estimated to go extinct within 19 years.
With African wild dog existing in such fragmented populations, their extreme inbreeding avoidance behavior may very well spell doom for them.
Inbreeding avoidance has been a very useful for wild dogs as they have evolved. With the exception of the island foxes and domestic dogs, inbreeding is not a frequent occurrence among members of Canidae, and it has contributed to greater genetic diversity in many wild dog populations than might otherwise be assumed.
But there is also a paradox to this inbreeding avoidance.
If animals have such a resistance to doing so, they are unlikely to do so should their numbers drop significantly and the only available mates be close relatives.
And this can kill them off far more rapidly than the effects of an inbreeding depression.
Further, we know that lots of wild Carnivons have survived extreme genetic bottlenecks.
Cheetahs are the textbook example. Their population experienced a massive crash about 10,000 years ago, losing over 90 percent of their genetic variability. Cheetahs were able to survive this bottleneck and were thriving until about a 150 years ago.
Northern elephant seals are another example of a Carnivoran surviving an extreme genetic bottleneck. Whalers would stop by the seals’ breeding beaches to augment their cargo, and by the end of the nineteenth century, there may have been as few as 20 northern elephant seals left. There are now 100,000 of them, and there is no evidence of any deleterious effects of inbreeding on the population, though they may be more susceptible to disease, pollution, and climate change issues. Of course, northern elephant seals harem breed, and only a few males of the species wind up siring the pups at any given time– a kind of natural popular sire effect. It’s very likely that elephant seals within the same populations were always in some way related, and because the animals had evolved this type of breeding system, they may have evolved a certain amount of inbreeding tolerance that hasn’t been observed in any species of dog, which almost universally reproduce within a bonded pair.
Inbreeding avoidance behaviors do keep populations genetically diverse.
But it can be an Achilles’ heel.
If a population is so adverse to inbreeding, it won’t be able to continue on if the only possible mated pairs are relatives.
Inbreeding avoidance behavior can be a boon to the long-term survival of a species.
But it can also be a great hindrance.::