It’s a relatively common idea that sexual selection works in exactly one way: males develop exaggerated traits (peacock feathers and stag’s antlers) to compete for female attention, because males want to spread their sperm everywhere while females want to only mate with the best. Unfortunately, it turns out that the real situation is more complicated.
A replication of the initial sexual selection study showed that, if one counted fruit flies that died before hatching and not just fruit flies that lived, the mathematics work out completely differently. More adults mate multiple times than previously predicted, fewer don’t mate at all, and there are more mothers than supposed. In short, there is very little evidence for picky mothers and promiscuous fathers– at least in that species of fruit fly.
Some reporting explained this as “sexual selection has been disproven forever!”, which is of course not true. There are lots of species that do follow the males-compete-for-female-attention model. It’s just not the only possible model and shouldn’t be the default assumption. Animal species’s sexualities are incredibly diverse: even in the great apes family, we have chimpanzees (alpha male/beta male structure), bonobos (let’s have sex with everyone!), orangutans (solitary except when occasionally they meet up for sex), and gorillas (lady gorillas hit on the the gentleman gorillas). A lot depends on the environment, the life cycle of the species, and sheer bloody random chance.
Of course, the natural question here is “what about humans?” Humans are and have always been an intensely cultural species; therefore, I think it’s fallacious to explain most complex behaviors with a simplistic “because evolution.” (Or, for that matter, with a simplistic “because culture.” Most behaviors have both a cultural and a biological component. We might like sweets because that helped us survive in hunter-gatherer times, but Skittles are clearly a cultural artifact.)
I am not sure that the science is in to say any more than the broadest generalities about how humans as a species work. People of all genders try to be attractive to the people that they are attracted to, sometimes doing dangerous or ludicrous things to make this happen. (If they aren’t attracted to anyone, then fortunately they don’t have to worry about that shit.) In some cultures, being attractive is more important for one gender than for another: for instance, if you’re a 19th century middle-class British girl and choosing a good husband is the difference between poverty and wealth, you’re going to be far more concerned about your attractiveness than the average middle-class British guy of the period. (Note that this is the exact opposite of what sexual selection theory would predict.) What counts as attractive is incredibly culturally influenced– otherwise, explain to me how the Victorians had a fetish for girls with TB and why a billion Chinese women had their feet bound– although I’m not ruling out the idea that there are biological aspects.
Basically, you cannot say that “men compete for women and women choose whom they want to date.” That’s not even true for animals, and the evidence is far from in that it’s true for humans, and really those dudes on Reddit need to stop feeling sorry for themselves about how women have all the power in dating. Dating sucks for people of all genders.
And here I thought all this was common knowledge. Oy. I’m stupid. One addition: “although I’m not ruling out the idea that there are biological aspects” Sure there are (there can actually NOT be biol. aspects in behaviour, because behaviour IS something biological xD) You might not like that direction. I don’t, but evolution didn’t ask my flat-heeled opinion xD Handicap theory. It’s the whole peacock tail thing again: If you can endure a handicap and still be healthy and fertile, you’re more attractive. There’s a theory that this is why humans have those giant permanent breasts no other species… Read more »
“A replication of the initial sexual selection study showed that, if one count…”…
A replication of the initial sexual selection study showed that, if one counted fruit flies that died before hatching and not just fruit flies that lived, the mathematics work out completely differently. More adults mate multiple times than previously …
As sex ratio goes down in humans (fewer males to females), there’s a greater chance males will “display,” possibly because fewer stable males are there to “stop” them, and possibly because the females have to accept behavior that’s un-mensch-like to get a man at all. Rock singers benefit from a great choice of females (analogous to low sex-ratio,) and lead an r-type lifestyle pretty often.
More lesbiehaviour, too. Just like homosexual lovin’ occurs more in all-male societies, I expect that in all-female societies. And toys exist..::D Displaying only works if the display pleases the viewer and chooser, of course a display might also warn other men. (Guys with roaring cars built to be louder? Ha. THAT signal is NOT for the ladies.) To me it’s obvious that all genders do display in humans. (I can now only use stereotyps and mainstream culture for examples, sorry about that!) Look at male clothing and uniforms over time and culture and you will find a lot of stuff… Read more »
“really those dudes on Reddit need to stop feeling sorry for themselves about how women have all the power in dating. Dating sucks for people of all genders.” As you pointed out in your male privilige piece something sucking for everyone doesn’t mean that one group isn’t privilige. Given all the arguments that have been made that women are priviliged in this area I think you’ll have to have some actual arguments if you want to convince people otherwise. I also don’t see why you post this: “Basically, you cannot say that “men compete for women and women choose whom… Read more »
I have heard that the dominant view amongst women is that there is a shortage of attractive men, so women have to compete really hard, or settle for douche-bags….
…When was the opposite of attractive “douchebag”. Most of the douchebags I meet tend to lean towards the physically attractive side.
Well, it’s always been rather clear that different species behave different so the pressures of their specific sexual selection of course varies as well. Some species aren’t very picky about their mates, some are, and in some species the male is the picky one. Using other species as a model for humans just doesn’t work. Humans also have a lot of individual and cultural variation in their behavior. (As do some other animals, but not to as great extent.) Evolutionary psychology in general is pretty much completely Speculation. there might be some good ideas here and there, but even those… Read more »
I found Ozy’s post sort of random. So I tried to inject a little humor. I think God is usually laughing at us (in a nice way,) and this is another example. Another proof of this is the wave-particle contradiction in terms of light.
Speaking as a zoology undergrad, this isn’t really news in the field. Any decent evolution class will teach that, while female choice and male-male competition are general trends across species, they are not so common or without exception that they can just be assumed about any given species. Seahorses have females competing over males, k-selected species often adopt a social parenting strategy which has an entirely different set of evolutionary incentives, hermaphroditic species exist and also follow somewhat different rules, learned behavior exists and is much less predictable than genetics… If there is one constant in biology, it’s diversity, which… Read more »
Hear, hear
To add onto that, you can make almost anything sound sensible with evolutionary biology language. The real answer can only be derived from experiment, and experiments on human sexual choice are really really hard.
So we can’t know the answer.
Eeyup! Ethology/Zoology undergrad here to agree. And let’s be honest – Peacock sexual selection is SO unlike cervid (deer) sexual selection. Deer don’t flaunt their antlers for attention – they’re tools and weapons. This stuff might have been news in 1910, but not in 2012. Human sexual selection is incredibly complex – though we can see some hints of it, but it’s largely impossible to detangle from human culture. We don’t even know why human penises are so unlike any other ape penis (being enormous comparatively and lacking any kind of baculum). Boobs are also largely a mystery. I think… Read more »
Huh. While interesting, Hank, I kind of missed the point you seem to be about to make. Is it that, biologically (for a loose interpretation of biologically) humans are between monogamous and polygamous animals, so we should see a tendency towards both? Anyway, I also wanted to bring up my own two cents about sexual selection. I had always thought (and feel free to correct me here) that sexual selection of certain decorative traits appeared in the sex of the animal that had multiple mates. That is to say, in polygynous animals, the males were more visually impressive (or had… Read more »
Human testacle and penis size ratios to body weight are right at the dividing line between monogamous and polgynous species.
peacock feathers and dear antlers; male guppies have nice tails!
And yet female guppies will show preference to guppies that other females show preference for. “If she thinks he’s good, he must be good”. And peacock lekking systems are nuts and it’s often based on where you are in the lekking grounds (more toward the middle is better) in addition to showing the handicap-style fitness going on. (Or possibly sexy sons hypothesis, it’s not clear for peacocks whether this is “I survived this massive handicap” or “your sons will have more babies because I’m sexy and they’ll be sexy too”.) Take it from an ethology student, there is SO much… Read more »
Doh!
How silly of modern men not to realise they’re living in the 19th Century after all. I’ll just pop down t’mill and see what sort of dowry old ‘Ardcastle is giving away with young Ethel.