If inbreeding is so bad, then how is it that some highly inbred populations of lab mice or dogs or wild animals manage to thrive?
Although highly inbred animal populations exist (mostly created by human intervention), it is questionable to say that any such populations “thrive.” More accurately, they manage to survive for awhile. Inbred laboratory animals (mice, beagles, cavies) exist in protected environments largely free from environmental stress or challenge. Isolated inbred wild populations like the celebrated wolves of Isle Royale or the Cheetah are in reality struggling and vulnerable, ripe for extinction. Very soon (by nature’s timetable) they will no longer exist; nature is in no hurry either to create or to extinguish animal populations. That extremely inbred lab mice exist comfortably even in a protected environment is due largely to the fact that surviving strains have been successfully purged of many deleterious genes; their natural genetic load has been reduced by careful selection. Part of that selection process necessarily involves the fact that many bloodlines have been culled or discarded, or hav