Eve, by Cat Bohannon

This book is a romp! Science and a woman’s take on how to think of anatomy, physiology, and evolution as they all play out on a deep discussion of the the female body and how/why it came to be.

The hook: she points out in the introduction, that the business and process of getting drugs to market requires thorough testing to consider dosing, side effects, and benefits—-and all those studies, until recently were done only on men. She understands that studying drugs in patients are much more reliable and hence easier in men (no hormone fluctuating, no early onset menopause, or pregnancies to mess with), but points out that not studying women lends itself to problems in the clinical setting: women metabolize drugs differently and sometimes in a manner affected by changing hormone levels. “That it is harder does not mean you should not look…..”

She makes a stand at the end of the introduction: biological outward genitalia are  set and a developed finding 99% of the time, reflecting our evolution as a species.  Gender association is a feeling  and is 100% mediated in the brain (also hard to study)—and is a different more complicated if not nuanced thing.

Bohanon does a, “quantum leap” of thinking when discussing milk and its evolution. This is material I have never touched on before. For example: Milk is not just food for the human infant. Some of the sugars in milk are not digestible by humans but are digested by gut bacteria, suggesting a co-evolution—“commensurate hosts.” A newborn infant needs to have its colon colonized by the right bacteria in order to have a functional bowel and it has to be done quickly. Oh, and don’t forget the antibody absorption!

She sites studies suggesting that infants imbibing milk high in cortisol (suggesting the mother is stressed) are less likely to take risks and are less social as they develop. Low cortisol in milk is associated with an infant more social and interested in exploration. I would love to see if that is a reproducible finding.....Antibodies are found in milk aiding an infant to fight infection and she raises the point that the act of suckling finds “back spit” being injected into the milk ducts of the mother.  She suggests that there are feedback loops to modify the subsequent milk’s consituents based on this process.

Whoa.

The onset of menstruation occurs earlier in western / industrial societies. She attributes this to diet: hormones in food we eat and the tendency for children in these societies to be fatter than children raised rural/third world.

Perception is different between men and women: She starts with a wonderful anecdote about posing in a life drawing class to make money when in college. Men tended to draw her breasts larger than they actually are. This changed only with practice and attention to mechanics of accurate drawing being acquired. She also notes that as vulnerable as one might feel in her position, she in fact, “owned the room.”

Hearing: apparently women cue in high frequency sounds better than men and the usual evolutionary thinking on this revolves around a baby’s cry (higher frequencies). She notes with aging, men are not annoyed by high frequency sounds as much as their females peers. For me, this discussion feels like a brain process that is complicated enough with distraction and, “other focus” playing a role.  Also, I don’t hear so well. Kernie hears everything.

Smell: she states that there are sex differences with respect to demonstrating a refined sense of smell. Supporting this claim: Female mice can differentiate smells better than males  but this disappears when they are castrated. Male mice, once castrated appear to improve on their “smell scores.” Neuroanatomy studies show that women pack more neurons in the olfactory foci…..A crude measure, to be sure—smaller brains function as well as larger ones--but wow! We DO percieve the world differently.

Vision: Random fact: New world monkeys are color blind and African monkeys, linked to our ancestry, share our X linked gene for color blindness which affects 10% of the population, mostly males.

Legs: Exercise physiology clearly demonstrates that male humans have denser muscle mass and generally are stronger. Short bursts of exercise (running, climbing a tree in an emergency, boxing, wrestling, and so on ) all find males demonstrating dominance. There is on exception: super marathons whose records and dominance are held by women. (Wikkipedia data suggests men do in fact outperform in Ultramarathons). Endurance is her key concept for suggesting women made the change from living in a forest canopy to walking in savannas actually work. Corollary: combat teams do better when in-shape women are on board.

Reproduction: We suck at this when compared to other primates-our gestational time frames and length of labor are much much longer than those of our nearest primate relatives. Our babies have these huge heads……and the pelvic opening is not much larger than other primates. It gets worse: we have to nurture our babies much longer (before they are independent) than other primates. How in the world did we survive?  Evolutionary thinking finds us raising children in groups. Mothers giving birth are assisted—-something not seen in other primates and facilitated by community.

Biology of Intelligence—this topic is a minefield; economic status usually can normalize differences in outcomes when measuring success in a college application or completing a degree. When comparing male and female IQ testing, most differences are subtle and depend on testing circumstances and structure. Females often out perform males in math and reading — at least until puberty and then that reverses. She has a lot to say about that process.

Language: virtually all of us learn to speak from a mother. The cuing and foundations start in utero where the mother can be heard. Languages often have a terminal “pitch” of sound at the end of a sentence when spoken (French goes up and German goes down). The cry of a baby will mimic this at two months!  There are critical time periods that set one’s cadence of speech marking it as your original language. This is taught by example with mothers. Lastly, she discusses “motherese” a pitch and tones mothers across all cultures use when talking to babies and pets…….

Having mothered, advanced the species by teaching speech, and working with tools, we come to an evolutionary enigma: human primates go through menopause, and assuming they did not die in childbirth or from trauma, often live a long time after menopause. Why is that an advantage, evolutionarily? Orcas are one of a handful of mammals with this pattern. Our lives are very different from Orcas, so, what gives?  The most common theory is that our advancement as a species hinges on our social lives—we function in groups, communicating with language. Non family and even strangers can coordinate activities and be extremely effective with survival in mind and few species can touch that. So a woman, no longer wearing her body out carrying pregnancies to term has a lot to offer a group (child rearing, memory, problem solving something new to the young people) improved survivability. Once more, she claims women have a better expiration date….

The longest chapter is on love. Try plugging that into an evolutionary framework. Well, consider monogamy. Or not! After all, there are harems and polygamy in many human societies. She looks at primates which have societies with a lead male who would kill babies he thought were not his own. She notes that many species see this behavior and an adaptation (evolution?) Is to have “sneaky sex” ie be pregnant but have relations with the new head of the tribe and keep the baby safe as the head will assume paternity…..  She argues that the evolution of cooperative societies of humans as a net benefit had to happen before monogamy could really function safely—and with it, sentiment and love.

She identifies matriarchal primate societies (bonobos and baboons) noting there is not competition with males but influence and group activities for strength reflected by females. Of interest, she states that rape is rare in all primates other than homo sapiens.

Societies with structure and cooperation occur with many primates but with humans, where official status of monogamy (think of the queen even though we all know the king has other mates) leads to leadership being inherited. This only occurs with us humans; all other primates have to fight to gain their status as leaders.

She casts her gaze on female attitudes and notes that while women don’t like that men are not monogamous, really, their emotional attention is heightened dramatically over the question of a woman who consorts with a married man voluntarily. She concludes, women can be sexists! I think there is more to that.

With love and loyalty and social standing, she points out what is obvious: going through history (and not clearly evolutionary change) as a species, we are incredible adaptable: monogamy, polygamy, hierarchical placement of people by status, sex, and race, and equal opportunity as  guiding principles. Male dominant vs Female Dominant. Violence as taken for granted vs violence as not acceptable. It is not clear what this adaptabilty means with the scope of a hundred thousand years coming up. That makes me the optimist!

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