Quote Originally Posted by LotsaBalls View Post
I need to take a genetics class... All this pheno whoknow idontknow stuff is hard to follow. So, recessive lethal. How do you prove that? Would it be just the fact of no super spider existing?
Taking biology classes is a wonderful idea! I highly encourage it for anyone in the hobby. Heck you don't even really need a class. Wikipedia (longer articles with plenty of references are best) and textbooks get you quite a ways on your own.

As far as proving recessive lethality.. with the jaguar trait in carpet pythons, it's easy. Hatchlings don't fully develop in the egg, and they die off before melanin production occurs. You get all-white baby snakes, dead in their eggs, that ALMOST go full term. It's worked out to be about on average 1/4 of a clutch is dead white snakes from a jag x jag breeding, so it's been inferred that the jaguar trait is homozygous-lethal.

There is less evidence of recessive lethality in spider ball pythons, but there are "guesses". The only real evidence that we have is that there SHOULD have been a homozygous spider produced if it was capable of being produced. On top of that, while we don't understand the exact relation between the presence of the spider trait and the neurological defects known as the "spider wobble", it really wouldn't surprise me that a relation between those defects and homozygous lethality exists.

While there are plenty of holes in the theory that the spider trait is homozygous-lethal (mostly due to lack of concrete evidence, which in itself is a pretty big hole), the lack of a homozygous spider existing poses some serious questions.

We're going to see this issue brought up in the next couple years a bit more I think. With the strong influx of large numbers of bumblebees, I think it's likely that we will see plenty of bumblebee x (spider combo) pairings in the not too distant future. Maybe we'll get more data and be able to form a theory better backed up by actual evidence rather than a lack of evidence.