I did not think any fertilized ovum would be reabsorbed by a female--I thought that applied only to follicles that had not fully developed and been fertilized. Even if the embryo dies very early, wouldn't it still be shelled, and wind up being laid as an 'unfertilized egg'? Not a slug, but a shelled egg that just collapses in the first week.

My snakes lay some of these every year anyhow.

I have spiders, and I have personally never, ever seen a head wobble in a normal spider-sib. Wobble in spiders varies a lot within a clutch, too.

I would suspect the scant few reported cases of head-wobble in normal sibs are actually due to some other problem that caused neurological issues in some of the clutch, such as temperature spiking. Spiders are one of the more religiously out-crossed morphs.

The dominant pinstripe was proven when it sired a bunch of clutches that hatched all pins, if I remember.