Homo Sapiens ad Astra and the Butterfly

This is a republication of an article I wrote on my blog a while back. It bears repeating to the Mad Genii, as it is directly related to writing science fiction. We change, on the most fundamental level. We change in an astonishingly short time, and that change is not limited to butterflies. Humans adapt as well as any other creature – arguably better.

I’d promised a follow-up to my post on genetic paucity and the link it has to rapid extinction, as a few readers were interested in the genetic changes that happen in a captive population. Those changes mean that raising the last few members of a species to release back into the wild are very difficult, if not impossible. They are also very interesting as a model for humans, and as a window into adaptation on a global scale. I’m going to be wandering a lot deeper into the weeds of ‘what if?’ than I normally do in my science essays with this one, but bear with me.

First of all, the studies and modeling done on captive populations of different species both confirmed the hypothesis that yes, keeping animals and organisms in cages (so to speak in some cases) changes them. What seems to have shocked the scientists is just how fast that can happen. Domestication of animals is long known to have affected species in odd and wonderful ways – just look at the dog, for instance. There are hundreds of variations on Canis domesticus, which all descend from a now-extinct canid, not the wolf as was commonly believed. Shadowdancer shared an article about the effects on foxes when they are kept and bred in captivity, things like coloration changes, tail configuration changes, things you wouldn’t assume would happen just because they were removed from the pressures of the wild.

The study I had seen on the Cabbage White Butterfly had looked at changes that were potentially fatal in the wild. Butterflies raised in cages grew smaller wings, heavier bodies, and laid more eggs. The net effect of all of those was a butterfly that could fly less, slower, and while more eggs means larger population, it makes the females even more vulnerable to predation due to the added mass slowing them even more. The population was chosen for the study because there was a large extant wild population (the caterpillar of Pieris brassicae is a common pest) to compare with a population that had been raised in captivity for between 100-150 generations. The implications for captive animal populations are clear: being held captive will change you.

Just how long until we see an effect? Well, in studies done on Drosophila, a common model organism, a doubling in fecundity was seen in only eight generations. Eight. In human terms, using the rough rule of thumb of twenty years to a generation (arguably this could be telescoped further, as I’ll discuss shortly), that’s a mere 160 years. Which means, in genetic terms, that the United States of America has existed for more than long enough to affect the genes of those who are born to it. Granted that a fly is not a human, but the model organisms give us ways to look at genetic adaptation over many generations in a way that, say, raising elephants cannot. But elephants are not immune from this, either. It’s simply that it would take longer to see the adaptations as their generational span is vastly longer than a fly or a snail or even a fox.

The implications for successfully re-wilding a captive population are clear: that which we return to nature is not what was there to begin with. As I mentioned in my earlier discussion of this, there is some argument for the pointlessness of attempting it, as extinction is a natural and normal process. However, exploring the concept further, we find wild horses, and humans.

I grew up with mustangs. I read books about wild horses, I dreamed of seeing them running wild and free, and when I was six, my mother ‘adopted’ a mustang from the BLM (which will always mean Bureau of Land Management to me, no matter the modern attempt to co-opt the acronym). That was the first of several mustangs to come live with us, and they only fueled my interest in the wild horses of the west. Pre-Columbian era, there were no horses in the Americas. Or rather, there had been, but they had become extinct. The saying among the peoples of the Americas who joyously adopted the horse as quickly as they could was that ‘the grass remembers the horse.’

The horses who were brought to the Americas, and who quickly re-populated it, were not, of course, quite the horses who were discovered later to have been here, through investigation of the fossil record. But they were close enough that they could walk into the ecological niches and start grazing. They fit in well. Later, much later, the scrubby wild horses that had survived in the centuries between the 1500s and early 1900s were joined by a fresh influx of genes in the form of horses no longer needed on farms who were simply turned out to join the wild ones. Any kid who has read up on Misty of Chincoteague, Dick Francis’s racing mysteries, and other books of that sort, is aware that there are wild herds and tame from coast to coast in the USA, and that they are all different. They have adapted to their environment, from the high-altitude ponies of the Andes to the delicate long-legged thoroughbred of the Kentucky bluegrass.

Horses came back from extinction through the path of captivity. Their passage changed them, formed them into what they are now, so you can trot a Shetland up to a Clydesdale and wonder if they are the same species (they are, although you’d have to use artificial insemination, the draft mare, and some wild-eyed wonder to see what came of it). Humans haven’t varied quite that much. Yes, there are superficial differences, but it’s more the internal I’m interested in.

Remember how the captivity changed the butterfly? There was a conversation among friends a while back, I don’t recall exactly who all was taking part in it, but something that came up caught my imagination and left me wondering. How much does living in our increasingly urban coasts affect the genetics of humans? Does, for instance, the obesity ‘epidemic’ have as much to do with the loss of pressure of hunger and adversity? The butterflies, freed of the need to fly away from predators and hunt for food far and wide, became less fleet, fatter, and able to have more babies. Our genes are shaped much more by our heritage than we once thought – the field of epigenetics is just now starting to unfold. What does this urban lifestyle do to us? I’m not suggesting that we need to flee cities – I’m not fond of them, but they are a useful tool – I’m simply wondering what if we also adapt? What if we change in captivity? What comes next?

What is happening elsewhere in our world? Generation telescoping means that if a baby is born to a mother merely 15 years of age – not unheard of in cultures and countries on this globe of ours – that eight generations can collapse to 120 years. In other words, 1900 to now. That’s… not a lot of time, relative to known history. We are a changing species, but into what?

We no longer have an easy frontier to challenge our adventurers. The genes of pioneers are an interesting quandary: where do the Odd go when there are no more fringes of society reaching out into the unknown? I look upward at the stars, knowing that’s the last hope. Captivity in animal populations is recommended to be ‘fragmented’ or given many different places to breed in, and then those populations to be crossed back in order to foster genetic diversity and slow the adaptations to captivity that would be fatal to a wild population. Humans, right now, don’t have that luxury. We’re very nearly a global population and that last bit of a gap is closing fast. We need to fragment, too. Which means we need to make a giant leap off this mudball and upward to the stars and the potential to change and adapt and reach for the next big thing out there, somewhere.

21 thoughts on “Homo Sapiens ad Astra and the Butterfly

  1. I head about a brilliant plan [waits for groans to subside] that crossed a Shetland pony with a Quarter Horse. The goal was pony size and hardiness, but with the good temperament of that particular line of Quarter Horse. That’s not what they got. They got the foul temper of the pony line with the stamina of the Quarter Horse. She was a real [long string of derogatory adjectives and nouns here] to handle.

    1. Lots of “Let’s make an ideal crossbreed” work out that way — no matter how useful the parents, in the offspring you get the worst and most-intentionally-suppressed traits coming to the fore. Sometimes you can breed around that and insert the desired trait, sometimes not. A few that I know about…

      Sheepdog x flock guardian produced not the dog that can both herd and guard, but stock killers — the sheepdog’s desire to nip stock to make ’em move, plus the flock guardian’s complete lack of reserve when it decides something need killing. (The ones I know about were also dangerous to humans, and were eventually all put down.)

      Poodle x Labrador (first done by the Guide Dogs in pursuit of a hypoallergenic dog for their clients) got not an agreeable working dog, but creatively-useless clowns — the Lab’s deeper intelligence and the Poodle’s desire to evade responsibility. 100% fail rate.

      Pointer x Labrador (covertly, in a major bloodline in 1946 in the U.S., to “add drive” to those stodgy retrievers) did not produce a faster-working retriever that would point, but rather a dog that wants to bolt, at the least stress over the hills and gone (a retriever needs to hunt close to the gun, but a horseback-hunting pointer needs to range wide), and will blink birds (pointing is “Oh that smells lovely but let’s not touch the nasty thing”), ie. will refuse to pick them up, and often can’t swim well either. Since then most of the damage has dissipated into the Lab’s huge gene pool, and only the pointing gene remains, but for 5 or 6 generations, linebreeding on one particularly famous dog (whose great-great granddaddy on both sides was that pointer) would reliably produce bolters, no matter how close the parents liked to work. [This might not have been all bad, since the dog that was cuckoo’d out of the pedigree in 1946 had some other deleterious cross close up, and reliably produced dogs that would not go in the water.]

      As to humans, consider that you’re confirming that culture and genetics are indeed linked, as some of us out here have been observing for a while. City selects for city boy; after six generations of that, what use is he on a frontier?? he might adapt, but chances are he won’t, or not well. Frontiers are explored and initially settled by Odds, for good reason… being largely throwbacks to the wild type, with all its potential for future adaptations.


      Bi-polar: the delusion that you’re Roald Amundsen.

      1. Funny, I was just discussing this with my daughter (a special-ed teacher). I pointed out that, along with the similar ‘look’ in families, other traits bred true:
        – temperament
        – introversion/extroversion
        – types of giftedness
        – ability to focus and use sustained attention on a task (or lack of it)
        – charm/ability to lie convincingly vs. social awkwardness
        – willingness to sacrifice for others vs. selfishness in looking out for self only

        Just to name a few. True in animals – always look for temperament, rather than looks. True for humans, as well.

    2. Somewhere I read about a woman who proclaimed that she wanted a daughter sired by a man famous for his intelligence.

      Her “theory” was that with her beauty and his intelligence, her daughter would “rule the world”.

      Since she said this to the gentleman in question, he gave the following (roughly) response.

      “The child could have my looks and your intelligence.” 😈

      1. I’ve joked before that my husband and I are elf and hobbit.

        One of our daughters got his height and my build; the other got his build and my height. At least as preschoolers.

        This means that they were wearing the same sized clothes, and got really tired of being asked if they were twins. And learned that looking at someone like they’re an idiot and informing them you’re two years older than your sister was rude, and mommy would object.

        1. My sisters and I, and sometimes our mother, were often taken for twins.

          The irony is that my mother IS a twin, and was once introduced to her twin.

  2. — Which means we need to make a giant leap off this mudball and upward to the stars… —

    Yes, the sooner the better, and not just for reasons of genetic differentiation. But how can we the probably Earthbound — I shan’t speak for anyone else, but I’m getting a bit old for adventures in space — do anything to contribute to that end?

    There are serious problems to be solved if the aim is to colonize the Moon or another planet: propulsion, long-term life support, and terraforming are the ones that come most readily to mind. Existing technology is weak in all three areas. (We simply can’t keep using step rockets; they’re far too expensive for what they deliver.) But we can’t ring up Amazon and order brand new and superior technologies. No, not even if you’re a Prime customer.

    We might have an easier time establishing enduring habitats in orbit, perhaps at the Lagrange points. At least that way, terraforming would cease to be a consideration. However, questions concerning long-term residence in very weak or no gravity would have to be addressed.

    Where are the visionaries who will take the critical technologies past the current restrictions and boundaries? How do we tease them forward?

    1. What we really need is another Earth we can colonize. Which means going to other star systems. I wonder if ultimately that would take less time and resources than colonizing and taming the utterly hostile environments that make up the rest of Sol system.

    2. Simple truth is that we live at the bottom of a one G gravity well, and climbing out of it is horribly costly. Currently the only enterprises that justify the costs are the telecommunications industry and Earth observation. Sure, ISS is a useful research tool, but you don’t see anyone much proposing building more of them, at least no one with the wearwithall to actually fund one. And the several proposals for tourist jaunts into space are almost exclusively suborbital for a host of reasons based on physics and orbital mechanics.
      Current rocket technology is at its bleeding edge, requiring vast efforts for the tiniest of improvements in thrust and lift. There really is no where to go there.
      In round numbers a manned space launch will run about a billion dollars. Economy of scale, meaning lots of flights, can cut that back, perhaps as much as in half.
      A reference moon mission should require either one or two launches depending on configuration. Last time I was involved in an analysis of NASA’s reference Mars mission we figured on nine launches for a single mission, seven if they let us use nuclear engines. All for a mission duration of 2.5 years for a visit of a few weeks by between four and six astronauts.
      All this to say that current and potential advances in rocket technology are sufficient to let us touch space, but there is no way for it to allow us to colonize space. For that to happen we need a fundamentally different approach, some motive technology other than riding a Roman candle into the ether. And that quantum leap, if it exists, will be found by some team of lab coated nerds in a research center working under a DARPA grant or some such. Or a group of American educated foreign nationals working in some mysterious lab funded by their government.

  3. They fit in well. Later, much later, the scrubby wild horses that had survived in the centuries between the 1500s and early 1900s were joined by a fresh influx of genes in the form of horses no longer needed on farms who were simply turned out to join the wild ones

    Also via herd management– in the high desert, you went out, shot the head stallion, put your own horse out, and caught the resulting babies. Made sure they had feed during bad winters, upkept the fences, generally did a hands-off but there sort of management but did manage them so the herds didn’t become four-hoofed locusts.

    Basically, free range horse herding.

    There are still people who are red hot pissed about the state/feds stealing those horse herds, too, and you can see the decline in the stock between when it was managed and…well, now.

    I know it was a well established practice 110 years ago, when my Scottish ancestors got over here, because Grandma had a lot to say about it.

  4. When you think of stories like this, and reflect on the changes the environment has wrought upon us I’m always struck by one thing: North America is big. Bigger than those of us who live here often realize and wayyyyy bigger than Europeans seem to realize.

    In Canada if you drive an hour out of most cities you will find nothing. Fields. The curvature of the earth and the terrain itself will hide almost everything else. One hour. Less than a hundred miles (in general, obviously there might be a town or something exactly at the one hour point but the point mostly stands correct).

    Weirdest thing about it though is how few city dwellers seem to realize this. Like New York is full, right? But I’ve heard upstate New York is forests, fields, and empty. Toronto is much the same. Densely packed but Ontario is huge and mostly empty.

    So when people talk about preserving our wilderness I glance at them and wonder what they’re talking about; most of Canada is untrammeled wilderness. The upper half is nearly unfarmable. Sure, we log, and that changes things but we now replant by law.

    It’s as if two different realities exist, the one where cities comprise 1/1000th (or less) of the landmass but due to their relative importance (and feeling of importance) believe they represent 1/2 or 2/3. Not in terms of actual numbers in their head but in their weighting of significance.

    An amusing thing about the wild horse though is that it’s essentially a non-native aggressive intruder into the ecosystem and by their rhetoric and beliefs it should be managed down to non-existence. But they’re cute so they don’t want to do that.

    A wildlife policy that you know is based partly on the attractiveness of the animals in question does not seem like it would stand up to the rigors of science.


    1. If there is a town at that one hour point and it’s farmland, you can walk for half an hour along the road and get the same effect.

      If there’s forested area, ten minutes.

  5. It strikes me that long-term existence on a spaceship, or in a colony habitat on a hostile world is just about as captive as it’s possible to get.
    There may be liberation in the outer dark, but only when attached to very short tethers. (Or the sweet release of death.)

    1. Yes. And on arrival, they’ll be effectively colonial serfs implementing a planned economy (brr!) because there likely isn’t going to be such a surplus of labor and material that random colonists can walk away and do their own thing.

      About the best scenario I can come up with is that the colony is so successful it doesn’t stay totalitarian forever, but if it’s baked in from the beginning, it would be hard to shake off.

      1. Eh, Massachusetts was set up to be a theocracy and failed because of that whole generations thing.

Comments are closed.

Up ↑

%d bloggers like this: