Coronavirus is killing more men than women. In its first six weeks almost equal numbers of males and females were infected with the disease, but only 1.7% of the women went on to die, compared with 2.8% of the men.
Scientists think they know why: women's immune systems are stronger than men's. They're built that way.
Dr Sharon Moalem, a Canadian-born physician, rare disease specialist and author, has a theory that women are genetically tougher than men. In 2016 Moalem and his wife, Anna, were driving in Toronto.
A car ran through a red light and smashed into them. "We rolled," he recalls. "The cabin, the roof, totally caved in. We were very lucky to be alive. If we hadn't ducked down, we would probably have been decapitated."
They were hospitalised for more than a month with very similar injuries. But here's the strange thing: Anna was released two weeks earlier than Sharon.
"What was really noticeable was the healing time," he says. "The superficial cuts, for example — her healing time was faster. I got more infections than she did, my infections didn't clear as fast and I just didn't get back on my feet to the same degree."
His delayed recovery and the resilience of his wife did not surprise him. To him it was more proof that women are genetically superior to men. After the crash, he decided to write a book about it — The Better Half: On the Genetic Superiority of Women.
The evidence is strong. Women on average live longer than men. More men are born than women — 105 to every 100 — but, by the age of 40, the numbers are equal and, by 100, 80% of the survivors are female.
Women suffer fewer congenital birth abnormalities — tongue-tie, webbed toes and so on — than men. Men are about 20% more likely to get cancer and 40% more likely to die from it. Male children are twice as likely to suffer developmental disabilities such as ADHD, autism, learning problems and stammering.
Women tend to have better colour vision than men and some are tetrachromatic, which means they may see up to 100 million colours, not the one million most men struggle by on.
Ah, you say, but men are physically stronger than women. Well, no, not in terms of survival. When Stalin's policies in Soviet Ukraine starved millions, more women than men survived.
Men are certainly more muscular and better than women at most sports requiring power. No female sprinter is going to beat Usain Bolt, and men still dominate at marathons. But men are not so good when it comes to extreme endurance contests such as ultramarathons.
"The further the race, the more difficult the conditions and that's when men start dropping off," Moalem says.
The point was dramatically made last year when Jasmin Paris, a 35-year-old vet and mother, won the 268-mile Montane Spine Race along the Pennine Way up to Scotland.
"She broke the course record by 12 hours. At the rest stations along the way, she was pumping breast milk for her baby while the men were flat out on the floor."
Moalem also cites the Transcontinental cycle race, a pedal across Europe of about 2500 miles. Last year that was also won by a woman, Fiona Kolbinger, a 24-year-old medical student from Germany. This is happening because, increasingly, women are taking part in events once thought too difficult for them.
In fact, they're easier for women than men. Why?
"We think it is twofold," Moalem says. "One reason is that women have a lower resting metabolic rate, so they don't exhaust themselves as easily. The other piece of this puzzle that I looked at was famine survival, for which women have an immense advantage. I think that's where the ultra-endurance performance comes from."
He does not mention the rigours of pregnancy, once compared to running a marathon daily. Surely this is the ultimate proof of his theory? Moalem is too much of a scientist to go there.
"Suffice to say that a mammalian pregnancy requires a staggering biological response and adaptation. Yet until we manage to get an XY male pregnant, there's really no way for us to make that comparison and know for certain.
But I would say that far more impressive even than a genetic female's capacity to support a pregnancy to term is their ability to make it across the supercentenarian finish line. There's really nothing biologically harder for a human to pull off then making it to 110 years of age and beyond."
Moalem is equally careful not to draw too many conclusions about coronavirus — yet.
"Yes, so far it seems that more men are unfortunately succumbing to Covid-19, [but] we will only know for certain a few years after the pandemic if more males were affected. That being said, Mers, another related coronavirus that we do have more experience with and more epidemiological data, does in fact kill more males."
Somehow, for millennia, science and society have managed to overlook all of this. We have preferred the strong-man myth. "As a physician and scientist, the schooling that I got was that men are stronger" — meaning not just more muscular but all-round more robust — "It took me 20 years to deconstruct that paradigm."
Moalem knows there is going to be resistance to his theory. "I thought a lot about that while I was considering whether to write this book. It's a dangerous idea and it's going to upset a lot of people. It probably has already. Whenever you're swapping paradigms, there's a lot of resistance. But it's such a fundamental rule of biology that ignoring it is to our detriment when it comes to the medical applications. That's what gave me the impetus and the courage to say, you know, it's time now for us to make a change."
One way in which it has been to our detriment is in drug prescriptions. Bizarrely, Moalem says, scientists prefer to use male mice to test drugs. "To this day, preclinical research does not require you to use both female and male mice," he says.
Of course, there are studies that use female mice, but scientists often veer towards using males because they are less hormonal than females, which, they say, makes for clearer data. But there's a drawback, says Moalem: as a result, doctors find that women report more side effects from drugs than men. This is not because they are weaker, but because they are being overdosed on the basis of tests performed on male mice. Women's bodies hold on to drugs, including alcohol, longer, so the effects and the side effects are intensified.
For Moalem, the central truth underlying his thesis is that women are better built. The reason fewer female babies are born than male is that the construction process is more tricky, so slightly more female embryos and foetuses are rejected before birth. "Building a woman is an immensely complicated process. It has to go perfectly. If it doesn't, then everything is lost."
Moalem believes that the reason for all this lies deep within women's cells. Humans normally have 23 pairs of chromosomes — gene-bearing coils of DNA — in each of our cells. But one of these pairs — the sex chromosomes — differs in men and women. In women, it consists of two so-called X chromosomes — one from her mother and one from her father; in men, it consists of an X from the mother and a Y from the father. The Y chromosome's primary function is to produce testes and sperm, and is relatively poor in genetic information compared with the X chromosome.
For years it was believed that one of the two X chromosomes in women was effectively silenced. This fed straight into the "men are stronger" mythology. There was even a set of novels and a TV series — The XYY Man — which suggested having two Ys made you stronger, inclined to criminality. This is nonsense.
In reality, about a quarter of the genes on the "silenced" X chromosome are still active and accessible to female cells. So she has two possible sources of genetic information to fight disease, hunger or exhaustion. Men only have one. So having two Xs is, in Moalem's view, the source of female superiority.
"We now know why it's so important, because so many of the genes that are used to make the brain are on the X chromosome. And so many of the genes that are involved in the immune function are on the X. It's like having 23 volumes of instruction manuals for your house.
"But the one that is the most crucial for humans is the one about the brain and immunity. Without immunity, we're not going to be around much."
Moalem is an energetic polymath. He was born in Montreal and now works and practises in New York, where he has become something of a media star. In 2007 his bestselling book Survival of the Sickest made the case that some diseases helped us live longer. His next bestseller, in 2009, was How Sex Works, which ran through all the latest material on sexuality and why people find each other attractive.
"I'm always driven by very simple questions or just a string of questions that eventually ends up with one question, which I then can't get any satisfactory answer for. And if I get blank stares or laughter, I know I'm onto something interesting."
So he goes for the big, hidden ideas and he sells them with fierce energy. He is 43 and has a taut, slightly corporate air, dressed in a bright blue suit and light brown wingtip shoes. He has an instinct for seeking out what others miss, oddities that point to a deeper, less familiar truth. The resilience of women, for example, was buried not just by mythology but also by misguided theory. He noticed this while still a student.
"Someone would say, well, why were most medical studies done using men? And they'd say, well, they're stronger. We don't want to take the risk of using a woman, who is the weaker sex; we may harm her. Men are made of stronger stuff and they can take it. That's what was implanted in me and my colleagues. For me, everything I was seeing was telling me the opposite. We confused the idea of being able to throw a spear farther than a woman and being able to run faster and lift more things that are heavy with an organismal strength."
Greater female longevity used to be explained by the fact that men behaved badly — they took more risks, went to war, smoked more, drank more, got into fights more and so on. But this did not explain male weaknesses that were clearly inborn.
"Besides the developmental errors that seem to happen more in males, the other thing I kept seeing was a survival advantage in neonatal intensive care units, with very young, very small children," Moalem says.
"When I would speak to the nurses, they were wells of wisdom because they'd been doing this same job for 30 years. They'd say, we've been telling physicians this for the longest time. Whenever we see a boy and a girl in similar circumstances, we're more concerned for the boys. So if we're seeing a survival advantage there, then it's not behavioural."
For women, there is a downside to all this. There's a perceived paradox about female longevity: although they live longer than men, they also tend to suffer more illnesses in their lives. This was a puzzle, but now, Moalem says, we may have solved it.
"It's not that women get more ill, it's that men get ill and die. So the fact is, it's not a paradox. The answer for it is simple — women are just not dying."
There is one type of illness that women suffer from more than men. The second X chromosome gives them the benefit of a more effective immune system, but it may also mean they are more vulnerable to autoimmune diseases in which the body attacks itself.
These include rheumatoid arthritis, coeliac disease, inflammatory bowel disease and more than 100 others. As with cancer, men are more likely to die from such diseases, but, unlike cancer, women are more likely to be afflicted in the first place.
So, will the world change when news of women's genetic superiority sinks in? "When any paradigm changes there are definitely societal changes associated with it. But the resistance that I'm getting when I say that women are biologically stronger than men is telling me that the opposite idea is still dominant right now. So many of the decisions we make in areas such as employment are affected by this. It's like with the ultramarathons.
Women were discouraged from doing these ultra-events because they are so arduous.
They thought there was no way that a woman could even do it. Then they allowed women to compete with men and then the women started beating the men. A woman can't win any race unless she runs it."
He thinks there may be a "reimagination" of what it means to be strong. "In the past, strength meant protecting yourself and your family, your tribe and your group. That relied on physical strength. But we have evolved as a society and now machines and technology provide more strength than a human is able to produce."
There's a danger here of new forms of anti-male prejudice and discrimination. But such attitudes are nowhere to be found in the science. The subtitle of Moalem's book is On the Genetic Superiority of Women. The keyword is "genetic". Genes don't make anybody "better" than anybody else, they just make them different.
Nature has made men and women fit for purpose — the first for physical strength, the second for the resilience to, in Moalem's words, "survive long enough to ensure the survival of our offspring — which in turn means the survival of us all".
We are, in short, all in this survival game together, all essential and all equal.
* The Better Half: On the Genetic Superiority of Women by Sharon Moalem is published on April 7 (Allen Lane £20)
1.7% of women and 2.8% of men who caught coronavirus in the first six weeks died
Men are about 20% more likely to get cancer and are 40% more likely to die from it than women
Written by: Bryan Appleyard
© The Times of London