Tom,



First of all, i think you expressed your question exceptionally well.



Second, I think most breeders would agree that given an alternative, they'd rather not inbreed. Inbreeding/linebreeding can express both strengths and weaknesses. A canary breeder might inbreed to produce a "line" of bigger canaries or canaries with better songs. Conversely, you could linebreed humans to produce children with cystic fibrosis, a fatal inheritable condition. CF is a recessive trait, as is albinism in cal kings, for example. So inbreeding can improve offspring, or weaken them, depending on the genetics of the parent stock. In the case of color morphs, people line breed or inbreed to produce more of the desired color characteristic. Others might line breed for size, or reproductive vigor, or to preserve the genetics of a locale.



Keep in mind that it's easy to construct an example in which a het x albino pairing would be MORE closely related than another pairing of two relatively unrelated albinos. The analyses here require really clear thinking!



Third, I'd ask respondents to this thread to also answer this question:



Have you ever bred two unrelated snakes and gotten any of the following outcomes:

1. One eyed snakes or snakes with no eyes at all.

2. Kinked backs and tails

3. Eggs that go full term only to leave fully formed babies dead in the egg

4. Eggs that come out infertile from day 1, or go bad soon after being deposited



My intent in asking is probably transparent: Yes, breeders get those results from unrelated specimens, too. It would take a huge data pool to determine whether the undesirable results occur more often from inbred pairings than unrelated pairings. I personally suspect they would, but not with much statistical significance. The problem is that when any of those undesirable outcomes occurs people seek an explanation, much as early humans described Thor hurling lightning bolts to explain the consequences of thunderstorms (hope i got that right!). Reports of genetic defects need to be examined with just as much skepticism as reports of divine intervention or paranormal experiences.



good post, tom, i look forward to seeing what develops.



peace

terry

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