I don't see how you arrived at this conclusion, this logic seems to be flawed.
Of course it can be an explanation for a trait. If you are genetically predisposed to high cholesterol, is that advantageous or disadvantageous? There's simply too little pressure to do anything about it.
Phenotypes aren't required to change in the smallest imaginable step. It's not implausible that nature decided "hey this next bee gets some furry yellow stripes, but also barbs" and here we are.
Not everything is optimal in the extreme. For all we know there have been many, many bees without barbs, but the bar to pass that on as an advantage is very high. The odds of a bee reproducing aren't even that high to begin with.
If barbed stingers were a variation that occurred in some individual bees, but many other bees didn't have them, like predisposition to cholesterol in humans, then I'd agree.
But a trait can't be universal in a species, and even in many related species, unless there is explicit selective pressure for that trait, or if it's a remnant from a common ancestor that had it. Your high cholesterol predisposition example is actually perfect, it shows what happens with traits that don't have significant pressure for or against them: they remain confined to a subset of the population.
> Phenotypes aren't required to change in the smallest imaginable step. It's not implausible that nature decided "hey this next bee gets some furry yellow stripes, but also barbs" and here we are.
They generally are. The likelihood of a random mutation that produces several phenotypal changes but leaves the organism still viable is extremely low.
What makes you believe they are not a "variation" in individual bees? Colony genetics are fascinating and can facilitate some pretty extreme variation.
Could a single queen's mutation be responsible for all barbs? You have some hidden constraints here that I don't think we agree on.
> They generally are. The likelihood of a random mutation that produces several phenotypal changes but leaves the organism still viable is extremely low.
This is simply wrong. There are always plenty of potential mutations that cripple viability, sure. But pleiotropy in general is relatively common. In some species more than others.
Your reasoning here is heavily flawed. You firmly believe evolution and genetics work in a particular way that simply does not reflect reality. You are putting your belief in "survival of the fittest" first. I encourage you to broaden your horizons.
Why not? Honest question.
Intuitively, I'd say that there are plenty of traits that propagate as long as they aren't expensive in terms of genetic survival. It's the nature of random genetic mutation, random traits will develop and some of them won't really affect survival and may propagate.
I don’t know where you got that. It seems perfectly plausible that the stingers evolved in the superorganism, and that the selective pressure was something like “drones protect the hive via stingers which kill them” versus “drones can’t sting at all”.
I'm not at all sure this is true - I don't know the evolutionary history of bees, but it seems unlikely that some kind of solitary proto-bees would have died after a sting. And even if this were true, we should still wonder why that proto-bee evolved to have this suicide stinger in the first place.
"It's not a big disadvantage to survival" can't be the explanation for a trait, unless that trait is a remnant from an ancestor where it brought an advantage (like the hip bones in whales - hip bones are obviously useful in land-based mammals, and whales are descendants of those).
Sp the question is: why did some organism ever evolve a stinger that kills it, how was that ever something that made some organism survive better than its brethren that didn't have this trait?