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But the result will only reinforce the existing norm: fewer women will die of cardiac events because they’ll recognize their symptoms and go to hospitals sooner than they might otherwise, and the doctors there will treat them with the appropriate level of care.
While most people thought of COVID-19 as a lung disease, many now think it would be better modeled as a cardiovascular disease, given that thousands of tiny blood clots clog up the lungs, each of which triggers yet more local inflammation and cell death, resulting in a particularly horrific bloody cascade toward lung failure.
Lungs, a bit like the brain, are incredibly foldy, containing a surface area equivalent to half a basketball court.
But as time wore on, it became clearer: pregnant women were more susceptible than most people their age to the deadlier forms of COVID-19.
many different lifestyle choices influence one’s overall cancer risk: eating charred and fatty foods, sugar consumption, exposure to toxic chemicals, alcohol, failing to get enough exercise, stress…Simply knocking back one alcoholic drink a day raises an American woman’s risk of breast cancer by 14 percent.
One in two men worldwide will suffer from some form of cancer before they die. For women, it’s one in three.
Cancer occurring in one’s youth is strongly tied to having a Y chromosome, and cancer in old age is slightly less so.
Worldwide, in any given year, for every four boys under age fourteen who are diagnosed with cancer, only three girls will be;
men in their seventies (should they survive that long) are only slightly more likely to receive such a diagnosis than women of the same age.
One central reason most researchers think that may be the case is that the Y chromosome is tiny compared with the X chromosome: The X carries about eight hundred genes, while the Y only carries about a hundred to two hundred, leaving large portions of the X un-partnered in the male cell.
The reason that matters, of course, is that in the womb female embryos shut off or “inactivate” one of their two X chromosomes, presumably so they don’t double code for things and gum up the works.
This turns out to be true except for about fifty of those eight hundred genes, as researchers just discovered in 2017; some of those genes seem particularly important for cellular DNA self-regulation and metabolism—precisely the things a cancer cell tends to screw up, both when tumors form and in determining how fast they’ll grow, reproduce, and eventually metastasize.
We used to think all of a baby’s mitochondria and cytoplasm came from its mother, but recent studies have shown that sometimes sperm manage to get some of its material into the egg (Luo, 2013). It seems to be a kind of breakthrough process, however, with the sperm mitochondrial DNA mostly eaten, jettisoned, or drowned out by the egg’s cellular engines after fertilization
Of those we’re able to easily study, that is—the arctic bowhead whale seems to live two hundred years or longer, but we don’t know enough about their sex lives to establish whether older females are commonly giving birth at two hundred. We only learned they live as long as they do because we’ve found nineteenth-century harpoons in their sides. It’s very hard to study the longevity of whales that live in deep, cold water, particularly when most scientists are only professionally active for forty-odd years.
You do a lot of math when you’re broke.
We live, at all times, both in the present and in the long rivers of evolutionary time.
It’s the unusual way we love one another: our distinctive, complex, often bizarre and overpowering love bonds, and the way we’re able to extend those loving bonds to people we’re not related to.
the evolutionary origins of human marriage can be found in that first moment when some ancient ape traded meat for sex.
How did human beings evolve to love one another, and what role did women have in that evolution?
Is it prostitutes all the way down?
WRITTEN ON THE BODY
Among our fellow primates, there are two physical traits usually tied to polygyny: teeth and body weight. The males have big canines—the eyeteeth, or “fangs”—and their bodies are significantly larger and heavier than the females’.
And while their canines are smaller than those of gorillas or baboons, they’re still far more intimidating than any hominid’s.
Looking scary is generally good enough.
In the biology of sex differences, this is a general principle: the harder it is for males to get a chance to reproduce, the harder they compete with one another for a chance to have sex.
human males are only 15 percent heavier than females on average.
By way of comparison, adult male chimps are 21 percent heavier than females, male bonobos are 23 percent heavier, and silverback gorillas are a whopping 54 percent heavier.
By the time hominins arrived, however, the males were getting smaller and the females were getting larger.
That is, females such as Lucy were only about 15 percent smaller than the males.
And the males were already losing their big canines.
human men still tend to have larger teeth. But the show canines are mostly gone.
That means Solomon and his wives, and any other harems you’ve heard of, represent a very recent innovation in our sex lives.
The trend, if anything, is convergence: men’s bodies getting lighter and less intimidating, and women’s getting bigger.
Likewise, if food was especially scarce, smaller bodies with bigger fat stores made more sense, rather than large bodies with a lot of bone and muscle.
Promiscuous primates have gigantic balls.
In primates, testicle size is so deeply linked to male competition that sometimes their size will even change depending on the social status of their owners.
Human males, as a rule, have medium-size balls. A bit like Goldilocks: not too
Medium balls, runny sperm, short teeth, smaller bodies—that doesn’t sound like King Solomon to me. Doesn’t sound like King Chimp, either. If ancient hominins had a lot of male-to-male competition going on, our bodies are pretty good at hiding the story.
This is one of the more taboo subjects in the science of human sexuality—whether human males evolved to be prolific rapists.
Given that there’s very little rape in chimp society, there was probably even less among ancient hominins.
Aggression, coercion, general harassment, yes, but rape is incredibly rare.
But given enough time—the sort of evolutionary scale that allows some genes to be favored in response to environmental pressure—the female body is likely to produce counterploys. So if ancient hominins were particularly rapey, it’s reasonable to think some trace of that history would be written on our bodies.
So if the human penis and vagina evolved in a rape-fueled competition, our current anatomy doesn’t betray that history.
If anything, our bodies seem to reveal a lot of consensual sex without very much violent male competition, and maybe even a continually reduced competition over time, with our older ancestors being more competitive, and our more recent ancestors getting less and less so.
Thus, the paper concludes, the human penis evolved its particular shape in order to help men with sperm competition.
human males take, on average, more than four times as long to ejaculate during sex as chimpanzees.
In a rape-driven reproductive environment, you’d expect all sorts of signs of violent male competition, both in men’s bodies and in women’s reproductive organs. Human beings don’t have those signs.
So, no matter the prevalence of rape in modern times, our human ancestors probably weren’t very rapey, they probably didn’t have a lot of violent competition for mates, and they were only about as promiscuous as you’d expect from a medium-balled primate.
Monogamy. The most popular argument in the scientific literature is that ancient humans started being monogamous and didn’t have to compete as much for mates.
The females, meanwhile, spend a few million years getting a bit bigger, a bit taller, in part because they’re eating well off their mate’s contributions.
