The Meat of Man the Hunter
Men and Women have been shaped by their respective subsistence strategies.
"The gods Ninurta and Nergal, who love my priesthood, gave me the wild animals of the plains, commanding me to hunt” - Ashurnasirpal II, 865 BC.
How Extensive is male specialization in hunting? In 98.4% (861/875) of cultures in the ethnographic atlas and in 87.3% (138/158) of cultures in the Standard cross-cultural sample, males make the sole contribution to hunting, in the rest, males make the lioness share of the contribution.1
In the 20 cultures in the Standard cross-cultural sample in which females contribute to hunting, males still supply the overall majority of calories from hunting.
Why are Men from across all cultures specialized in hunting? Like anything else in human behavior, the answer lies in the forces of natural selection. In 22 Societies from across the world, especially good hunters are reported to have more wives.2
Where quantitive evidence exists, looking into the reproductive success of ‘good’ and ‘poor’ hunters, and of ‘Hunters’ and ‘non-hunters’. We see that good hunters in Ache and !Kung communities have 1.5 times as many kids as poor hunters and that hunters have twice as many kids as non-hunters among Lamalera islanders and Merian turtle hunters.3
In two more hunter-gatherers groups, the Hazda and Siberian fishermen4, hunting skill is positively correlated with fertility, among the Hadza being a good hunter is the single most valued trait in a potential husband.5
For the Meriam turtle hunters, we even have a sibling study showing that the large differences in reproductive success remain when looking at siblings within the same family6 (one hunt the other doesn’t), indicating that it is the activity of hunting that is casual in the reproductive differential between hunters and non-hunters rather than some familial confound.
So male hunting specialization and the selective forces that shaped it are cross-cultural meaning they go back to our common ancestor or older. Hunting is old, the oldest spears discovered are the 380,000-400,000 Schöningen spears from the German bogs. Those spears weren’t used by homo sapiens ( we weren’t out of Africa yet) but by one of our relatives, maybe Neanderthals, if so, spear hunting possibly goes back even further to our common ancestor with Neanderthals and Denisovans. Perhaps Homo- Ergaster was spear hunting, looking at the physiology of the skeleton of the 1.6 million years old Turkana Boy, with his long forearms and fully upright posture he was certainly capable of doing so, and the Acheulian hand-axes he was manufacturing were just as complicated to make as a pointy stick.
Those long eons of selection for hunting in Men had their effect on the physiology and cognitive abilities of Men. One such effect should be selection for upper-bodied strength, In Hazda hunting reputation is correlated with greater upper-body strength7, so it’s no surprise that male athletes can lift 30% more weight than Female athletes.8
We also naturally see large sex differences in throwing ability, from the earliest ages there is a 1.5 S.D sex difference in throwing ability, which grows to a 3.5 S.D in adulthood, this is a larger sex difference than the more well-known male-female difference in hand grip strength.
Those throwing ability differences are so large that 70-74 Male athletes in throwing sports still outperformed the youngest Female athletes.9
Since evolution doesn’t stop below the neck, selection for the physiology that prompts hunting success also means selection for the cognitive abilities that would do the same, that is why Men are better at visualizing the motion of objects through space. There is an early arising sex difference in spatial perception and spatial visualization that reaches a 2/3 standard deviation difference in adulthood10.
A review of several hundred cross-cultural studies showed that both Preubescent and adult Men are better at spatial reasoning, that Men are better at maze navigation, map reading, and route memorization, that Men engage in more exploratory behavior and have better mental rotation ability and outperform Women on Pigat’s water task11
The Fruits of Women the Gatherer
As Men were shaped by their subsistence strategy so were Women. Male Hazda cited foraging ability as the most important trait in a spouse12 but what sort of traits contribute to foraging success? a clue is found by looking at the sort of traits that have been under relaxed selection in groups as they moved from a diet based on foraging to one based on agriculture.
Those traits are related to color, smell, and taste perceptions, they are important because they help foragers distinguish between the enormous variety of potentially forageable food. For olfactory-related genes (which overlap with genes related to taste perception), we have genetic studies13 showing relaxed selection since the dawn of agriculture:
In humans, approximately 60-70% of olfactory genes are pseudogenes; this probably reflects a decreasing need for olfactory perception in great apes and especially in humans (Gilad, et al. 2003a; Rouquier, et al. 1998). Indeed, relaxed selection has been described for most human olfactory genes (Gilad, et al. 2003a; Somel, et al. 2013) leading to fast accumulation of mutations in these genes (Gilad, et al. 2003b; Miyata and Hayashida 1981). According to our results, this process has also been taking place during recent human microevolution.
On top of this evidence, we know groups like westerners and the swidden-horticulturalists Semelai display poor odor naming ability but in comparison their hunter-gatherer’s neighbor, the Semaq Beri, find odor naming as easy as color naming.
For color vision the story is the same, in a review of the rate of red-green color blindness among populations long settled, not-long settled (or of mixed heritage), and hunter-gatherers, hunter-gatherers had 2.5 times lower rates of color blindness than the long-settled populations.14
The rate of red-green color blindness was universally higher for Men than Women, Here are the results for hunter-gatherers in which for many groups the rate of color blindness among women was zero or close to zero.
Reviewing 95 cross-cultural studies, Women were found to be better at visual discrimination and color discrimination, to be better at identifying colors and odors, have higher olfactory sensitivity and acuity, and to have better taste acuity/sensitivity15.
All of the classical skills in which foragers are more skilled at.
Ethnographic atlas: https://d-place.org/parameters/EA051#0/0/0, SCCS: https://d-place.org/parameters/SCCS824#2/14.3/151.2
SCCS: https://d-place.org/parameters/SCCS867#2/14.3/151.2
In footnote 3, the first study.
ibid
Jumping and throwing performance in the World Masters’ Athletic Championships 1975-2016 , different weights are used for male and female athletes and for different age categories, but it just so happens males aged 70-74 use the same weights as the youngest female athletes except for the javelin throw in which the youngest female category throw 100g heavier javelins than males aged 70-74.
“Sex Differences: Summarizing More Than a Century of Scientific Research”, Tables in the image.
“Adaptation and Human Behavior - An Anthropological Perspective" - Figure 7.4
“Sex Differences: Summarizing More Than a Century of Scientific Research”, Tables at the image, plus table 4.1.3.1 for taste acuity.