Dimorphism came from natural selection, which resulted in a species that made it to the top of the food chain, and we've kept that status ever since.

It didn't happen because we were the biggest and baddest. It happened because of our social ability, our intelligence - and, including but not limited to, features of brain cells in our limbic system that would shut down when facing danger, allowing our crowning evolutionary achievement of executive function to don the day. The fact we're philosophizing and intellectualizing our own existence is evidence of our uniqueness that put us on top.

We're all human animals, female, male, androgynous alike, whether we like it or not. But we're unique enough it's really a waste of time to engage in comparing us to other species at such fundamental levels, especially those species at the bottom of the food chain. However, we still suffer heuristic, cognitive and social biases, and thinking errors from the animal within.

Dimorphism was essential to survival and our social nature survival during the Stone Age. The problem is although we're out of the Stone Age, it is still within us. Even our dimorphism is obsolete.

Expand full comment

(Sorry for taking so long to reply-- I could have sworn that your reply disappeared for at least a few days after it first appeared, and I haven't been back to it since.)

I was wrong about the term 'natural philosophy'. What I meant was the idea -- whose name I cannot find -- that things in nature were designed for human convenience and pleasure.

Your 'take on why males exist':1) So that women can pick and choose mates (which helps the species because women are very wise when it comes to evaluating genes).2) Men are useful (to other human beings) because they are stronger.3) Women like their company.

You seem to be laboring under some very serious misconceptions of how evolution works. I don't mean to sound unkind, but if you want to understand this subject, you will have to endure getting a lot of your biological (and perhaps political) ideas knocked down.

Expand full comment

Sexual dimorphism lowers extinction risk:


Expand full comment

I've read Dawkins.

Is this what you mean by "Natural Philosophy"? (quoting John Herschel's wikipedia entry here): John Herschel's "preliminary discourse on the study of natural philosophy, published early in 1831 as part of Dionysius Lardner's Cabinet cyclopædia, set out methods of scientific investigation with an orderly relationship between observation and theorising. He described nature as being governed by laws which were difficult to discern or to state mathematically, and the highest aim of natural philosophy was understanding these laws through inductive reasoning, finding a single unifying explanation for a phenomenon."

If so, I don't see how that would be a problem for either science in general or the ideas I was presenting, but feel free to elaborate as I may well be missing your point.

Expand full comment

"Natural Philosophy": All 3 points or which one of them?

Expand full comment

If you're actually interested in the subject of this discussion, I recommend The Selfish Gene, by Richard Dawkins. I think the idea you're presenting used to be called "natural philosophy", and Darwin and Wallace pretty much demolished it.

Expand full comment

Sorry to be late to the discussion, I only just discovered this blog. As a female, I must say it is unexpected but rather refreshing to find a discussion taking place largely amongst men, which is pondering the utility of men's very existence.

However, I don't think the answer to the question is very difficult to find. My take on why males exist:

1. Diversity: if women get to choose which men to mate with (believe me it's not a given that the woman always gets her choice!), they can choose the best available genes to produce offspring. The choice can be adjusted for the environment/circumstances they find themselves in, so it allows the species to adapt more quickly. Diversity of selection strengthens the survival chances of the species.

2. Usefulness: Having husbands/fathers around can be very useful. On average, men are larger, stronger and faster. If they act in the interest of the family as a whole, they can contribute great value for many practical matters. This is clearly an aid to survival of the species.

(Note: best providers of genes and best husbands/fathers are not necessarily the same group, thus we see some men nurturing other men's genetic offspring).

3. Women like men and enjoy their company: despite what men may think, women do actually like men when they are behaving like reasonable human beings. Women place great value on the love, affection, romance, empathy, understanding etc to be found in a good partner. Whilst I'm not sure how to quantify this in terms of how it aids the survival of the species, it is one of the things that makes that survival worthwhile. Perhaps we can say it gives the species the will to live, because it makes life enjoyable. (The question of whether there is any point in surviving simply for the sake of survival itself could perhaps be debated elsewhere....)

Expand full comment

«After reading a dozen or so papers, I can report: we just have no idea what that advantage is.»

After a long time wondering the same I think that I came up with a very plausible explanation whose implications are unfortunately politically incorrect:

* Suppose there is an expensive gestation period/effort.* Suppose each individual is driven by genes to maximize their progeny.* Suppose that there are 10 hermaphrodites, and 1 of them is the most "attractive" and uses their male organs to impregnate the other 9.

That is, if impregnating another hermaphrodite is much cheaper than gestation, behaving as "just-a-male" is a huge advantage for outbreeding other hermaphrodites. Now of course if all hermaphrodites evolves into "just-a-male" bodies the species disappears, so eventually there is a stable dynamic balance.

An implication is that human mothers are sort-of hermaphrodites where their male sons are their male reproductive organs...

Expand full comment

That's anisogamy, no? It's about why there are male and female gametes. That seems like a rather different issue to me. Hermaphrodites have male and female gametes too.

Expand full comment

I'm with it Robin. Glad you continue to you put your thoughts and observations out there.

Expand full comment

"We men might feel a bit better about our place in the world if we could better understood our positive contributions."

Thanks for the opportunity to explain the naturalistic fallacy. (Commenter Jim Balter below saw this already.) The "purpose" or contribution of a person cannot be assumed to be identical to their evolutionary "purpose." To think it is is to run afoul of Kant's is/ought distinction: To know that something or someone 'is' a certain way is not to know that it 'ought' to be that way. So, for example, knowing that the evolutionary "purpose" of every organism is to reproduce its genes successfully tells me nothing about my purpose as a person—it tells me nothing about what I ought to do. Robin Hanson agrees with this intuitively, because there is no way that writing this blog is helping him reproduce his genes, yet he keeps doing it.

If knowing our non-sexed, generic, human evolutionary purpose does not help us understand our "contributions" as humans, knowing the specific evolutionary purpose of our sex won't help us understand the contribution of ourselves as men.

Expand full comment

Why take time to extinction as a negative metric? If "we" evolve quick "we" out compete in many niches even though it turns out "we" doesn't mean our species . Isn't this just another example of the selfish gene? And doesn't memetics and (if it happens) self modifying AI show how it isn't just the gene that's selfish, but the thing that is imperfectly copied? And that faster wins over slower in the sense that slower tends to be food for the faster?

Expand full comment

> I don't follow ...

Sorry to hear that. It's a pretty basic point about fitness.

"Anyway, via Tim Tyler's essay, which TGGP kindly linked below"

I've read the other comments and links; there's no need to repeat and summarize them.

Expand full comment

"I'm less sure what the advantage of being female over being a hermaphrodite could be"If you had two sets of genitals instead of one, there would obviously be increased mortality risks.

I don't follow ...

Anyway, via Tim Tyler's essay, which TGGP kindly linked below, I found another reason to specialize in being female rather than hermaphroditic, that I hadn't seen elsewhere, from Matt Ridley's The Red Queen: non-nuclear DNA (mitochondria and plastids). This is only passed to offspring from the mother (well, usually), so from a non-nuclear gene's perspective, it is better to suppress the male function of a hermaphrodite and promote the female function, and indeed, this is found in some plants:

Hermaphrodites are in a state of constant battle against rebellious organelle genes trying to destroy their male parts. Male killer genes have been found in more than 140 species of plant. They grow flowers but the male anthers are stunted or withered. Seed but no pollen is produced. Invariably of the cause of this sterility is a gene that lies inside an organelle, not a nuclear gene.

Fascinating! Dunno if there's any evidence that this is what caused the evolution of pure female specialization in animals, but it's plausible.

Expand full comment

"I'm less sure what the advantage of being female over being a hermaphrodite could be"If you had two sets of genitals instead of one, there would obviously be increased mortality risks.

"There could also be path-dependency at work here"

Well of course. This is why it's ridiculous to talk about one strategy among several extant strategies "winning" ... sexual reproduction, asexual reproduction, parthenogenesis, hermaphodites, various degrees of sexual dimorphism ... all of these strategies exist in different species and even in different populations of the same species that exist in different niches, different circumstances, and different histories.

Expand full comment

" a lack of mating opportunities can certainly happen for mobile organisms too"

This is the wrong way around. Lots of things *can* happen, but it's what predominately *does* happen that's the driving factor:

The costs of roving inseminators are balanced by the benefit of increased diversity. The benefit is greatly reduced in sessile organisms, so it's better not to pay the costs.

"Maybe the risk to males of being locked out of mating opportunities is offset by the rewards that accrue to the most successful males"

These things need to be measured on genes, not individuals.

"the risk to mobile female organisms of being unable to find a mate "

The very essence of female vs. male is mate selection vs. mate seeking, so yes, the risk you mention is minimal and discountable.

Expand full comment