Seems that there is broad consensus that the evidence substantiates sexual selection is very important guide to evolution, and sexual selection (in many cases) is a type of intelligent guidance.
My quote, in context, is about divine intelligent guidance. I do not think divine guidance is substantiated. I do not think the evidence substantiates the claim that there was no guidance either.
I would disagree strongly. The organisms doing the selecting donāt know that theyāre selecting the fittest mates (or demonstrating their greater fitness to rivals). Itās not a conscious choice at all.
The whole mate selection topic seems like obfuscation: the notion that animals choose their mates is used as an opening wedge for the notion that selection is sometimes conscious rather than truly random, and then a god is slipped into that (allegedly) newly created gap.
The two things are not the same, the logic doesnāt hold.
There is a huge spectrum of intelligence in the animal kingdom, so I donāt know if this can be said with any certainty. How does sexual selection work among other apes, such as the gorilla or chimp?
Another very interesting example are various bird species that construct very ornately decorated nests to attract mates:
You canāt help but think there is some sort of intelligence in both building the nests and in choosing the best nest for a mate.
Certainly: horse or dog or cattle or chicken of fish breeding for particular characteristics is intelligent guidance. I donāt think anyone is claiming that intelligent selection never occurs. The question is about whether it occurs at every step of the Tree of Life from unicellular organisms forward, well before human beings got involved in selective breeding.
There is a huge range of selection mechanisms. Some relate to either being a better predator or avoiding predators better, some to surviving other environmental conditions and so on.
Even among mate selection, there are beauty strategies by some birds and some fish, song strategies by some birds, sheer volume for the White Bellbird, ornate nest building and decoration for bower birds, building the biggest pile of compost for Australian bush turkeys and so on.
This is by no means an exhaustive list.
We can think about it, but Iām not sure a female tropical fish with a brain the size of a flea who lets the most beautiful male fertilise her eggs is really participating in intelligent selectionā¦
And the point remains: this kind of selection is qualitatively unlike human selective breeding is qualitatively unlike divine intervention.
First off, those arenāt nests. Theyāre bowers, structures made by the males to attract females. The females apparently make their choices depending on some features of the bowers. But in what way is that intelligent guidance? Are plants exercising intelligent guidance when they produce red flowers to attract hummingbirds? How does the action of the plant differ from that of the male bird?
I love this topic, and this comment by @swamidass captures one aspect that is really important. I do understand why others resist the implication of āintelligent guidanceā when discussing sexual selection, but I think itās a reasonable way to think about most sexual selection. One big reason why (and yes this is a bit of a semantic point) is Joshuaās separation of āintelligenceā from consciousness.
Dan Dennettās most recent writing is up for discussion elsewhere on the forum, and while I havenāt read it yet, I suspect it will address these kinds of concepts. A major theme of Dennettās is his claim/observation that systems (not just biological) are typically made of subsystems that exhibit ācompetence without comprehension.ā (Nice old piece by Dennett at the Atlantic on this.)
To me, it is reasonable to talk about āguidanceā in contexts like sexual selection because agents and minds are involved, decisively. An animal might not āknow whyā it likes those kinds of flowers or that kind of mating call, but it āknowsā that it likes those things and it makes decisions on that basis. Animals weigh costs and benefits, make bets, engage in displays and in deception, and they do these things using behavior generated by minds. The topic becomes more baffling when sexual displays and rituals resist (or defy) utility-based explanation.
I get why people donāt want to call it āguidanceā much less āintelligent guidanceā but the alternatives are uninspiring linguistic contortions. Sexual selection makes no sense without minds and decisions and preferences. At least thatās how I see it.
Thanks, yes, I saw and acknowledged (to myself, but should have in the post!) that you made that point explicit.
I guess that really, then, the point you are making is pretty uncontroversial. It has been known pretty much from the start (before Darwin) that there were multipleā¦ I almost called them strategies, but that risks smuggling in intention or telology - letās say āmechanismsā for selection that are natural.
Natural selection has never been understood as meaning that any organism of a species has an exactly equal probability of breeding with every opposite-sex organism of the same species. Indeed, the notion of selection (part of it - the breeding part, not so much the surviving-long-enough-to-breed part) is pretty explicitly about the idea that certain traits increase the probability of successful breeding.
So I guess Iām not sure what the key point being made here isā¦
Yes and no. It is selection on a phenotypic trait (such as body size or butterfat content of milk) but without knowing how the genomics of the trait works. So it is analogous to natural selection which acts on the visible or measurable phenotype, with the gene frequencies changing as a consequence, without our knowing about what those genes do. So it is much more closely analogous to natural selection than to the actions of an ominiscient Designer who knows everything about what alleles at what loci do what.
This comment resonates with an entirely different philosophy that Iāve been reading about, which is Aristotelian philosophy. For Aristotle teleology is present in every natural phenomenon - even in a simple rock falling down to the ground - but it has nothing to do with what we now consider āconscious intentionā (i.e., Aristotle didnāt think rocks had consciousness or anything like that). Rather itās closer to the notion that the unfolding of many natural processes seem to have a certain directed-ness towards some intelligible end goal. Today many people dismiss this perception of an end to be an illusion that our minds impose on our basic sense perception to make sense of it, but Aristotle regarded it as real as all this other ābasic sense dataā we perceive.