Still More Lies
These are about the human sex difference, in a book that is literally dumbfounding
[Human identity, in the wake of the Woke academics]
This is just up today at Compact Magazine. Much longer version below, substantial preview for free, the whole thing for paid subs.
It is difficult to know how to respond to books like Agustin Fuentes’ Sex is a Spectrum.1
It was written by someone with an advanced degree and a long publication record, and it was published by a prestigious academic press. Yet it is transparently obvious, just a few pages in, that the author is playing a strange game that seems to have much less to do with trying to get to the truth of the matter than with asserting a predetermined answer no matter what the state of the evidence.
Fuentes, an anthropologist who has extensively studied macaques, begins with a simple primer on the evolution of sexual reproduction in life on the planet. But even here he makes startling critical claims about the mainstream evolutionary biological understanding of sex. He begins his discussion of how “interesting” sex is with an example of a fish species in which females can turn into males in given ecologies. The example, he says, is “not that weird” in biology. He provides no context for making sense of the example.
The reality is that species like this one (the bluehead wrasse) most definitely are weird, not only in the animal kingdom, but even among fish, which are among the most sexually fluid animals. (And this latter fact is perhaps why Fuentes rhetorically begins a book fundamentally about human beings by talking about fish, and an odd outlier among fish at that). Among fish, the number of species that are sexually fluid in this way is perhaps around 500. That sounds like an amazingly high number…unless you know what Fuentes does not tell you, which is that there are perhaps 34,000 known fish species. In other words, even in the most sexually fluid animals, transition between male and female by one individual can happen in only 1.5% of the total species. That is the definition of “weird,” i.e., unusual.
Fuentes spends time early in the book attacking a classic argument in evolutionary biology about how differences in male and female gametes (eggs and sperm) typically provoke many other differences in the two sexes. The argument is as follows, in brief. Female gametes are much costlier to make, as they are much larger than male gametes, and so females will have evolved to invest more energy in the reproductive chances of each gamete compared to males. This means, according to the Bateman-Trivers principle following from anisogamy, the development of different reproductive strategies for the two sexes, with subsequent differing likely effects on their physiologies, behaviors, etc.
Fuentes wants to challenge this logic by changing the involved math. We should not compare one egg to one sperm, he claims, because the number of sperm required to achieve fertilization is very high, given the difficulty and the defects present in a large percentage of them. One egg should be equated to about 15 million sperm, he suggests, and this will undo the argument from anisogamy about the sex difference.
But, again, he does not tell the reader essential context that invalidates his claim. Let us accept his equation of one egg to 15 million sperm. It is still the case that human males can produce that unit of even 15 million sperm much more economically than a female can produce a single egg. A female ovulates perhaps 500 eggs in her reproductive lifetime, while a male who ejaculated every day for sixty years (which is possible for a male of our species) would have had to make about 330 billion sperm. Healthy males can produce hundreds of millions of sperm daily, perhaps 500 billion or more in a lifetime. Even if 95% of those sperm are unviable for reproduction, that still leaves a male with 25 billion theoretical offspring in their gametes, compared to the 500 of females. The argument of anisogamy is wholly unchallenged by Fuentes’ new math.
He goes still further with his case against this central element of evolutionary biology. The Bateman-Trivers principle, he says flatly, is “mostly wrong,” and has been falsified in recent research. He cites a few articles in footnotes dating back a few decades that he claims demonstrate substantial errors in Bateman’s original research on the topic that invalidate the principle. But uncited by Fuentes is a 2023 Evolution article that corrects for all the methodological issues raised in this earlier literature and vindicates the Bateman-Trivers principle of sexual selection. In this 2023 study, unlike in any of the studies Fuentes approvingly cites, the authors empirically observed mating behavior of the organism Bateman studied (the fruit fly) and verified his claims.