We should colonize Mars, because it is inimical to human life, and therefore we’ll evolve super-fast!

Now this is high-quality click-bait: Near-Sighted Kids of Martian Colonists Could Find Sex With Earth-Humans Deadly. If only HG Wells had thought of that, his story would have had a more dramatic end as squinty-eyed Martian invaders dropped dead while trying to rape humans. The source for this peculiar claim isn’t that bad, but it’s still bad science. It’s about a guy who makes predictions about the future of human space colonists.

Solomon’s 2016 book, Future Humans: Inside the Science of Our Continuing Evolution, argues that evolution is still a force at play in modern humans. In an awe-inspiring TEDx talk in January 2018 — which inexplicably still has fewer than 1,000 views — Solomon outlined how humans would change — literally — after spending a generation or two living on Mars.

There’s the problem. These ideas are coming out of a TED talk, which is a good source for misinformation. I listened to it, and it was not awe-inspiring at all, but bad: it starts with the Elon-Muskian notion that the human race is doomed if we stay on Earth and we need to colonize other worlds. He lists a few ways we might go extinct, like a meteor strike, or erupting super-volcanoes, or using up all the resources on Earth. But he has a solution! One way to avoid such a fate would be to spread out beyond Earth, venturing out into the galaxy the way our ancestors spread from our birthplace in Africa.

I felt like raising my hand and mentioning that one and a quarter billion people still live in Africa, and that there are a lot of people who might wonder who you’re talking to with that “our ancestors” comment.

I’d also want to mention that changes occurring within two generations are going to be physiological adaptations, not evolutionary changes.

And galaxy? Seriously? He’s talking about a pie-in-the-sky effort to colonize Mars, practically our neighbor yet still almost impossible to reach. If we’ve got our pick of the entire galaxy, surely there are better choices than a cold, arid rock that is uninhabitable by humans.

It gets worse from there.

It’s a weird talk. The first half is all about how awful life on Mars would be for our species: the greatly reduced gravity is going to lead to calcium depletion and brittle bones, and much greater complications in pregnancy. The radiation is going to be a severe, even lethal problem — he points out that a native of Mars would receive 5,000 times the radiation dose of an inhabitant of Earth. Babies born on Mars will bear thousands of times more mutations than Earth babies, so miscarriages will be far more common.

You may be thinking that this sounds like a hell-hole, that the tiny population of humans who make it to Mars will be rapidly eliminated by fierce attrition, and that any colony will be far more doomed than anyone remaining on Earth. Not to this guy! He makes some very positive predictions about what will happen to this remote colony.

Far from waiting thousands of years to witness minuscule changes, Solomon instead believes that humans going to Mars could be on the verge of an evolutionary rollercoaster. He expects, among other things, that their bones will be stronger, their sight shorter, and that they’ll, at some point, have to stop having sex with Earth-humans.

But how? Solomon has an almost religious faith in the power of natural selection. Sure, there’ll be lots more mutations, but that just means evolutionary changes that might require thousands of years on Earth will occur in a few generations on Mars. He sort of sails over the fact that his hypothesis bypasses any opportunity for natural selection to work. He’s relying entirely on wishful thinking, that because brittle bones are a problem, a spontaneous mutation that counters it will arise, and rapidly spread through the colony…in a couple of generations. He doesn’t seem to be aware of the cost of selection. You’ve already got a tiny population, and you’re proposing that rare mutations will displace the majority of the individuals in a few generations? What kind of genetic load is he predicting? What is the effective population size of your colony?

“Evolution is faster or slower depending on how much of an advantage there is to having a certain mutation,” Solomon says. “If a mutation pops up for people living on Mars, and it gives them a 50-percent survival advantage, that’s a huge advantage, right? And that means that those individuals are going to be passing those genes on at a much higher rate than they otherwise would have.”

So we’re expecting an extremely rare advantageous mutation with extremely high adaptive value to “pop up” in a colony, while ignoring the greater likelihood of lethal or sterilizing mutations. We’ve got predictable increases in short-term adapations, like rising near-sightedness rates from living in close spaces, but we’ll pretend the predictable increases in cancer rates are negligible. Further, this population undergoing constant, rapid die-off with a few very rare benign mutations will, among other things, lose immune responses due to living in a sterile environment, which is how they’ll lose the ability to have sex with, or even contact with filthy Earth-humans, preventing the possibility of replacement of losses with new immigrants.

But cool, they might evolve new skin tones to cope with the radiation, because turning orange with more carotenes in your skin will be sufficiently protective to compensate for all the other damages.

He’s at least vaguely aware that they’re going to need a large, rich source of human genetic diversity to get all this “evolution” going.

It also means Musk and others will need to consider genetic diversity, to ensure a good mix throughout the population. Solomon argues for around 100,000 people migrating to Mars over the course of a few years, with the majority from Africa, as that is where humans see the greatest genetic diversity.

“If I were designing a human colony on Mars, I would want a population that would be hundreds of thousands of people, with representatives of every human population here on Earth,” Solomon says.

OK, how? At least this is a good example of a biologist telling physicists to do the impossible, rather than vice versa, but I’m just thinking this is silly. The resources required to ship hundreds of thousands of people to a place where the majority are going to die and fail might be better spent improving the sustainability of life on Earth. At least he did early on acknowledge that resource depletion might be a factor that would limit survivability, it just wasn’t clear that he wanted to engineer a situation to make his prophecy come true.

Finally, the fact that his solution relies entirely on unpredictable, chance mutations occurring so rapidly that natural selection has no time to work means that his fundamental premise, that he can make predictions about the fate of human colonies on other worlds, is absolute rubbish.

I don’t mind a little optimism, but it’s the internal contradictions and neglect of basic facts that gets to me.


  1. robert79 says

    He also seems to assume a mutation shows up in a population, instead of at first in an individual. I see one of two things happening:
    1) The Martian environment is extremely hostile to human life, except those with the new Mars-gene. Everyone dies, except for the one person who got the chance mutation, who now spends the rest of his life alone on Mars.
    2) The Martian environment is hostile to life, but not hostile enough to prevent people from procreating. Assuming our individual with the Mars gene and his ancestors are extremely prolific and prduce 10 offspring each, within two generations the Mars gene will have spread to 100 people, still a tiny fraction of a viable population. Assuming his descendants continue their prolific habits, withint 5 generations the colony starts dying out from inbreeding.

  2. says

    100 thousand people in a few years? The first Mars base will probably have enough problems supporting a couple dozen people for several years. This seems to be another guy who has put little though into logistics.

  3. Howard Brazee says

    It won’t be natural selection which changes us if we colonize Mars, it would be artificial selection. If we decide to direct how we change, we can survive there.

  4. doubtthat says

    Well shit, if we’re living on Mars, why worry about evolution? I assume that we will be able to edit genes in a significant way long before we can live on Mars.
    But also, why would living on a planet with less gravity make our bones stronger? Isn’t the exact opposite true?

  5. chrislawson says

    If a single mutation can give a huge 50% survival advantage, that seems to imply that the population will be completely unsustainable until the magic gene comes along, by which time there might not be enough people to save the colony anyway. Plus, it’s based on the wishful thinking that evolution will provide any mutation we need just when we need it. (If we throw all our infants into volcanoes, we’ll soon evolve volcanic heat resistance!)

    It’ll be Roanoke on Mars.

  6. says

    #5: because weak bones are bad, therefore he assumes a mutation to make stronger bones will naturally appear right away.

  7. lumipuna says

    If Chuck Tingle wrote that, I’d read it.

    Pounded In The Butt By A Traveler From Earth Who’s Wearing A Full Body Condom Because He Cares About My Safety, And Besides I Wouldn’t See Him Very Clearly Without My Glasses Anyway

  8. lanir says

    I see serious sociological problems with the way that’s being described. Going off the blog description, doesn’t seem worth it to watch the video. But let’s say for example you do have a clearly useful mutation. Let’s say it even happens three times in short order. Doesn’t sound likely to me but we’re starting from a place of optimism. So you have 3 people with a great genetic solution to one problem. What exactly is supposed to happen to them that their genes get spread all through the population? Are we imagining human genetic engineering? Are we engaging in a form of eugenics so that only their gametes get used for fertilization? Is that voluntary? Do they get a choice? Do the soon-to-be parents?

    Our relationships don’t work in ways that would be compatible with any of that. Some individuals can make choices that would cause parts of it to be possible but all of it? Society-wide? No. Try that unethical experiment and you’d just see a large group of people die off to natural casues or kill each other over social changes. Hard to say which would get them first.

  9. wzrd1 says

    #7, weak bones in what way? They’d be weak bones compared to those living on earth, but they’d still be strong enough to compensate for Martian gravity.
    The radiation problem is trivially resolvable as well, build a habitat underground, where the martian regolith and rock absorbs the radiation.
    The true threats are the threats that would be also present on the moon or simply in orbit, logistics. Food, medicine, clothing are absolute necessities and despite so many science fiction or science wishing pipedreams, aren’t going to resolve themselves, but need to be planned and prepared in advance.
    What he did was hand wave a few times, just to set up a chain of claims that do little more than illustrate his lack of comprehension of evolution. Evolution doesn’t happen in a planned, desirable outcome adaptation at a genetic level. Most mutations would either be benign or more commonly, lethal to the cell that had an error introduced in its genetic code. Even if a mutated cell survives, it’s even money in animals that the difference would trigger an immune response and that cell gets destroyed by the immune system.
    Evolution is a thoroughly random set of mutations that grant a null or even an advantage that is passed down to succeeding generations. A case in point, the e. coli long term evolution experiment took around 31000 generations to mutate enough to suddenly be able to process citrate, with a plentitude of changes that neither gave advantage nor disadvantage to the mutated cell line.
    In sexually reproducing species, any random mutation that is heritable is what counts, so the mutation has to be giving a significant advantage, which survives a relatively messy sexual reproduction process and manages to propagate slowly among a slowly growing population. That’s why founder effects are so slow in becoming common enough to be able to be detected in small, closely linked populations.

  10. garnetstar says

    Why does Solomon think that skin pigmentation will protect against, (or in any way affect) x-rays, gamma rays, cosmic rays? Is he that ignorant? The solution to the radiation problem is given by wzrd @#11.

    And, I thought that the extinction of species was far more common than successful adaptations (please correct if not)? Why isn’t he considering that?

    Very silly and unlikely.

  11. doubtthat says


    I read the dude as saying when humans, as we are currently constructed and developed on Earth, land on Mars, our bones will become stronger. So, stronger than they are now.
    I know astronauts in orbit have issues with bone density:

    But as PZ points out, this was not based on any reasoned understanding of biological processes, but just some L Ron Hubbard quality Sci-Fi theorizing.

  12. ardipithecus says

    Apparently he thinks there is a single gene for each characteristic. I wonder if his study of genetics ever got beyond looking up the definition in the dictionary.

  13. curbyrdogma says

    An orange race of people? Well, I’m all for the idea of building a colony on Mars. It could be marketed as an exclusive elite resort for all those wealthy enough to afford the ticket there. …You know, those types who aren’t doing our own planet any good, and believe in sci-fi movie scenarios. They’ll think it’s a place to escape threats of war and other problems on Earth that they largely caused. Make sure to include a galaxy-class golf course, of course.

    It could also be marketed to a certain type of people who believe they’ll be taken up into the heavens before Armageddon strikes. You know, those types that literally Believe in literal everything. The space craft could be called The Rapture. Only 144,000 tickets available.

    Later: “Oops! we had to cut the budget for our Martian program! Sorry!”

  14. nomdeplume says

    Sounds as if Lamarck has come back to life and is advising Musk on Mars colonisation.

  15. pipefighter says

    I don’t know… as a kid (and to a much lesser extent as an adult), I found the idea of terraforming fascinating. But it was always in a more hypothetical sense and not really geared toward human colonization. See, the idea that you could somehow make mars and Venus earthlike and give them moons and engineer life to survive and thrive there always seemed (again, from a hypothetical standpoint) pretty neat, but the idea of colonizing as a back up falls apart immediately. It’s a frozen, irradiated dust ball with soil toxic to life as we know it, practically no atmosphere and a fraction of the gravity. In some non anthropogenic doomsday scenario it would be a million times easier to ride it out in sealed habitats on earth and you’d save way more people. It’s almost like their immense wealth and insulation from the experiences of average people has caused them to forget we exist. Afterall, as long as the ubermench survives, why worry about the ants.

  16. nomdeplume says

    #13 That is a very misleading title. She (apparently) misinterpreted an arcane aspect of Victorian British Law, which seems to involve, as best I can tell, a judge sentencing someone ro death and then saying they had executed them as an indirect way of saying they hadn’t executed them but imprisoned them for life (I know, I know, go read it for yourself). So Wold had (again apparently) said someone was executed for sodomy, thus scaring the gay community of the 1850s, when in fact they had only been sentenced to death but not actually killed, thus scaring the gay community of the 1850s. Something of an academic gotcha moment I think.

  17. monad says

    Do carotenoids really protect against radiation? I thought carotenoids were there to scavenge chemical damage, and animals diverting some to their skin is either a way of advertising a good diet or just a handy way of producing colors. Has anyone heard of them being associated with ultraviolet like melanin is?

    Anyway, evolving fast is a pretty good reason not to go someplace. Evolution is a slow process of genes getting replaced within a population or a quick process of the population getting replaced, and nobody sensible wants to be part of the latter. You don’t get to evolve, after all, just survive and breed or not.

  18. nomdeplume says

    Just a thought, is Mr Trump’s coloration the result of him pre-adapting for life on Mars?

  19. chrislawson says

    wzrd1: “They’d be weak bones compared to those living on earth, but they’d still be strong enough to compensate for Martian gravity.”

    Possibly, but we don’t know that. Our studies of long-term bone physiology have taken place on Earth and in orbit, that is, 1g and 0g and nothing in between. While it’s possible that people living on Mars will develop enough bone strength to deal with falling over in Martian gravity, we can’t actually know what will happen until we can do long-term experiments at 0.4g.

  20. chrislawson says


    Read the whole thing and it looks pretty bad for Naomi Wolf’s research. It turns out that the prisoner was paroled after his supposed execution date. Even worse, the prisoner was convicted of sodomising a 6-year-old boy. Which means regardless of the sentence, this case wasn’t an example of the treatment of consensual adult homosexuality.

    Sure I can understand being tripped up by an archaic British legal term that has a completely different meaning to its surface wording. But what it looks like to me is that she only skimmed a summary of sentences rather than do the hard work of reading the details of the cases, which would have immediately cleared up her confusion. A task a radio interviewer achieved for a single interview yet she failed to do for an academic history, albeit one written for a popular market. She claimed in an Observer article “People widely believe that the last executions for sodomy were in 1830. But I read every Old Bailey record throughout the 19th century, so I know that not only did they continue; they got worse.” Clearly she did NOT read every Old Bailey record throughout the 19th century or she would never have made this mistake.

    Even worse, she now claims this error makes no difference to her argument. “I don’t think it takes many reports of a death sentence for a 14-year-old for sodomy, though later commuted, to really scare a 19-year-old gay man. This fear is the focus of my book.” Which of course fails to acknowledge that one of her key examples wasn’t even a case of consensual sodomy between adults, it was a child rape trial.

  21. nomdeplume says

    #25 fair enough, I hadn’t picked up on the 6 year old detail. But there seem to be other cases, and I think her comment about imposing a death sentence, even if later commuted (and what odd terminology to use to desribe this process!), was pretty threatening. Her major thesis is that in Britain public opinion, political and legal activity, against homosexuality worsened after the 1857 Bill, and she has a pretty detailed analysis of why this is so, and the reality of it (eg in censorship etc). I’m only a quarter of the way through the book, but it seems to me well argued, and horrifying, and with considerable implications for what was to happen in the 20th century.

  22. kaleberg says

    I always liked JBS Haldane’s essay, ‘The Last Judgement’, a bleak tale of the far future of mankind and its colonization of Venus. It’s disturbingly modern. I was always fond of the chilling line, “So rapid was our evolution that the crew of the last projectile to reach Venus were incapable of fertile unions with our inhabitants, and they were therefore used for experimental
    purposes. ” It’s online at archive.org.

    To be fair, Haldane wrote this essay in the 1920s when we knew diddly squat about the other planets and a tiny bit more about our own. Still, it is timeless.

  23. Anton Mates says

    He lists a few ways we might go extinct, like a meteor strike, or erupting super-volcanoes

    Um…there have been quite a few meteor strikes and erupting super-volcanoes in the last three billion years, and none of them have made the Earth a shittier place to live than modern Mars. That’s why life on Earth still, y’know, exists.

    If supermutations and zero-point-energy-powered unobtanium-sheathed Terraformitrons will let us live permanently on Mars, you might as well assume they’ll also make us asteroid-proof.

    Solomon argues for around 100,000 people migrating to Mars over the course of a few years, with the majority from Africa, as that is where humans see the greatest genetic diversity.

    Yes, black people will be thrilled to be shipped vast distances into a life of suffering, toil and literal dehumanization. It’ll feel just like old times!

  24. chrislawson says


    We’re way off topic here, and I have only read the very small extract of the book available on Amazon’s “Look Inside”. Even in the introductory material, I found several bad arguments. But if we just look at the data, Wolf is claiming that the Obscene Publications Act 1857 was a key point in the victimisation of homosexuals in the UK. The problem with this is the Old Bailey records show cases going back to 1684, well before the act in question, and although there is a bit of an uptick after the act, it remained an uncommon prosecution until well after 1857.

    The criminal codes against sodomy go back to Henry VIII’s charmingly named Buggery Act of 1533. Many criminal offences, including sexual acts, were revised and combined for the Offences Against the Person Act of 1828. In 1861 the Offences Against the Person Act was revised again and the death penalty for sodomy was repealed. The last execution for sodomy was in 1835. So it seems that rather than heralding a new era of repression for homosexuals, the time around the Obscene Publications Act represented a relaxing of the laws against it (needless to say, the laws were still indefensible from a human rights perspective).

    As for the rate of prosecutions, well the Old Bailey website gives a very simple search tool for generating statistics. And this is the graph of the number of prosecutions for sodomy/buggery in the database:


    1857 is in red. It took another 25-30 years for prosecutions to spike significantly. More importantly, it means that in John Addington Symonds’ lifetime nobody had been executed for sodomy, and by the time he was 20 the death penalty for sodomy had been revoked altogether. This is not to say that homosexuality was open and free at the time — but no historian has argued that.

    I’m interested to hear if Wolf mentions that Symonds famously declined to publish his 1857 book A Problem in Greek Ethics. Does she discuss why he chose to suppress his own book? Because the answer is not as simple as “homosexual literature was criminalised by the Obscene Publications Act.”

  25. unclefrogy says

    I will not take any ideas about colonizing Mars that does not address the problem of a very weak magnetic field first as anything other than a pipe dream fueled by some strong ganga. Any idea of anything other than a research base not unlike Antarctica is simply not serious.
    uncle frogy

  26. cartomancer says

    Pffft! I’ve already become short sighted and unable to have sex with other humans, and I didn’t have to go to Mars at all!

  27. danielrutter says

    This whole mis-argument is like a more complex version of how people think feral cats arise.

    You don’t get feral cats from escaped housecats. Well, you ALMOST never do.

    You know what happens when a domestic cat gets lost in the wild?

    It almost certainly dies, quite quickly. It never learned to hunt properly, and it’s screwed.

    Yes, there are feral cat populations (here in Australia we’ve got shitloads of them, they’re a serious environmental problem), but they are entirely the descendants of the very, very few fertile escapees, over the whole length of time domestic cats have been IN a given country, that made it.

    (This also explains the “GIANT feral cats!” that sometimes hit the news. Yeah, there are some startlingly large feral Felis catus, because the bigger they are the more of a survival advantage they have. Not, like, a hundred kilos, but I can believe twenty.)

    I can understand people wanting to go to Mars as an explicitly one-way trip, to live the rest of their life there in some habitat that provides reasonable safety and an opportunity to do useful work, with no particular need to reproduce. I can not understand people wanting to go to Mars if there’s literally one chance in a million that they will have any surviving offspring, even though that is the point, and they’re probably not going to even LIVE any longer than Fluffy the Siamese does in the outback.

  28. Rob Grigjanis says

    unclefrogy @31: I’ve seen some discussion recently about putting a magnetic field generator at the Sun-Mars L1 Lagrange point (see diagram at top right here). Probably old hat to Mars enthusiasts…

  29. Rich Woods says

    @chrislawson #30:

    Shouldn’t that be “NO, I WAS ONLY CALL’D UPON THAT MORNING”?

  30. chrislawson says

    Rich Woods

    It most definitely should be. This exchange looks particularly good in Pterrian formatting.

    Q. Do you know the prisoner?
    Death. I DO.
    Q. Do you know any thing of Vernham and Jane Porteir being married?
    Q. Where?
    Q. By whom were they married?
    Q. Who gave her away?
    Death. I DID.

  31. KG says

    It won’t be natural selection which changes us if we colonize Mars, it would be artificial selection. If we decide to direct how we change, we can survive there. – Howard Brazee@3

    Hell, if we decide to plan a transition to sustainability, we could even survive on earth!