I wrote earlier this week about science fiction, adaptation, and the human species over on my blog. in a nutshell, I’d written earlier about genes and how animals raised in captivity adapt to being in close quarters so quickly that it’s not really a viable option to raise an endangered population up to replace wild populations that are in danger of extinction. So what does this have to do with humans? Well, the conversation went something like ‘people who like to live in cities are weird’ (I’m shortening and paraphrasing) during a discussion about the coasts of the US, and how they have a tendency to vote a certain way. But, if you think about it, and I do, urbaniztion of a population does indeed do things to it. Similar things, I think, to the effects felt on a captive population of, say, butterflies. The butterflies get smaller wings, heavier bodies, and the ability to lay more eggs. So in effect they are going to do well in a cage where they can’t fly far, and would be easy prey for predators if they were put out of their nice safe cage.
Scientists are studying the effect that urban areas (generally defined as >300,000 people) have on plant and animal species. It’s no real stretch to imagine that living in a metroplex would affect humans as well, especially the poorer, less mobile parts of the population. And this is without even moving into the realm of science fiction. These studies have seen the effects of adaptation in as little as two generations – in my original article I was working off the premise that large effects of captivity were seen in Drosophila in eight generations: in human terms, 150 years. But two? A mere 30-40 years? (yes, thirty. Look at average primapara age for the inner-city populations).
All this is native to our design for adaptation and evolution of the genome, the in-built system to keep a species thriving in changing environments. If you don’t adapt quickly, you die – which was a larger part of what led to the passenger pigeon extinction than human predation on that species. Now, how about human tinkering with our own genes? We can do it – we’ve known that for a while, gentle readers. But a new paper on Crispr tells the tale of genes switched on inside an adult allowing that model organism (a mouse, in this case) to express genes they had been unable to do before, which led to the self-treatment of diabetes, kidney disease, and muscular dystrophy. This is exciting on so many levels, one of which is that this was done without having to completely break the DNA (a double-strand break) which means that the inadvertent introduction of mutations is not a concern.
Now, leap off this mudball and into the realm of science fiction. We see that if we do not maintain genetic diversity and gene flow between populations, we risk extinction. The ability to quickly adapt and overcome has long been a human realm. But what, as our populations grow larger and our urban areas soak up the majority of the humans on this planet, will happen to that diversity? What if we became like the passenger pigeon, and when sudden catastrophe came (a pandemic, an alien invasion, what-have-you) we were unable to adapt? The answer lies in the stars. But to get there, we’re going to have to adapt again and again, and our populations, like the urban rats of New York, will evolve and differentiate. Not enough to become separate species, unless we really start tinkering with Crispr… although as writers and speculators, we know that’s going to happen, don’t we? Humans will experiment, and they will experiment on themselves. I mean, it’s only a matter of a few years since the theorist about Heliobacter pylori decided to prove his hypothesis by drinking a beaker of that pathogen and giving himself ulcers. And another one ingested internal parasites on purpose to prove that they would put his autoimmune disease into remission. We’re crazy, we humans.
Which means that to write science fiction we have to think crazy, like a fox. To imagine the weirdest thing we can, and then take it a step weirder. There’s a whole field of stories that suddenly seems prophetic as we begin to truly understand the tools we have now, and the reality of epigenetics. Lamarck, who proposed the giraffe’s neck had become so long because it was necessary to reach the higher leaves (the ones out of reach of the eland and the gnu, which makes me think of Kipling’s stories), was laughed out of science when Darwin’s theory was all the rage, but in the long run it turns out that he was more right – and our genes more complex – than scientists at the time could possibly have imagined. Now, keep in mind that although we are now able to manipulate our own genome, and we have begun to grasp that natural selection is not always the random pattern once theorized with the epigenetic understanding that we are shaped by our ancestral diet and environment, we still do not fully understand what genes do. there are a few genes we can point out and say x does y. However, the vast number of them interact in complex and mysterious ways. We can’t just say, snip that gene out and cure cancer! because that’s not how it works.
Which means that in terms of story and speculation, we have worlds of room to draw conclusions and create plots that could be possible, or utterly wrong, but it’s so much fun to take the bleeding edge of science and play it out into what might be. What’s next?