For many years after the discovery of DNA a lot of what's found in that big double-helix was looked on as "junk." Scientists knew that genes code for the expression of specific proteins, but those genes only account for a small amount of the billions of "letters" in the recipe for humans. In fact, genes account for less than 2% of the DNA found in the nucleus of your cells. The rest of the DNA? Big shrug.
But if that other DNA was really just junk -- cast off bits of genes and sequences spliced from incomplete transcriptions of the 2% "good" DNA -- it would have a fairly random structure. It doesn't.
More recently, it's become clear that far from being useless, those other parts of the genome are vital in allowing the genes to do their work. There are some genes that contain regulatory sequences, and some genes that create proteins that affect the behavior of still other genes. But for the most part, the regulation of genes doesn't appear to happen in the genes themselves. It happens out there in the "non-coding DNA." In a way, the genes are like the keys of the instrument. It's not clear how much influence the non-coding DNA has over the genes, but in some cases that's where those notes in the genetic machine get instructions on when to turn on, when to turn off. It holds the sheet music of your biology.
This has a lot of implications. For one thing, it shows that the complexity of DNA in humans (or any organism) isn't just measured by the number of genes (a comforting pat on the head for those upset that humans have fewer genes than a potato). It also means that disorders that have their root in a DNA anomaly might not be easily pinned down to the presence or structure of a specific gene or even a group of genes. The problem can lay out there in that largely unexplored 98%. The keys on the genetic piano might be fine -- it's just the music that's changed.
When it comes to the broad group of "autism spectrum disorders," there are millions of adults and millions more children listening to some different version of the genetic tune. Some people with autism are very severely impacted. Others may have behavior that non-autistics simply view as "quirky," but are otherwise able to operate quite well in society. Temple Grandin is probably the best-known adult with autism, and we're fortunate that her particular form allows her to communicate the differences between how she thinks and responds and what we think of as normal. She's able to explain that her internal operations take place mostly using concrete images rather than abstract concepts, and that her emotional reactions to many actions is strikingly different.
But what if the autism isn't really so much a disorder as a preview? What if autism is what's next for humanity?
This isn't to suggest that there's a driving arrow behind evolution. There's nothing "pushing" for change, no anthropomorphic nature selecting for a goal. Instead there's just success and failure, specifically success and failure not on the battlefield, but the bedroom.
If it's true that autism spectrum disorders are particularly common in Silicon Valley and other high tech centers, maybe it's because the genes that are successful in these areas are genes that code for this disorder. Maybe it's the things that can sometimes be crippling -- the ability to concentrate fiercely, an obsession with detail, an insistence on order -- that also spell success. Maybe they are what a world that's increasingly tech-dependent demands. Maybe in a few generations it will be today's "normals" who are regarded as disabled -- clingy, flighty, crippled by a distracting need for emotional attachments. Relics in a world that's left them behind.
Or maybe not.
In any case, for this week's SEGO, here are some films and books that make some forecasts about the future of human evolution.
Darwin's Radio by Greg Bear
All that junk DNA plays a big role in this novel as the birth of an increasing number of unusual children causes uproar around the world. These births are associated with infection by the strange "Herod's flu," and women who have the flu are doomed to give birth to children that many people view as monsters. As public pressure grows, politicians begin a program to stamp out the flu -- and the children that result from it. But at the same time evidence is emerging that this isn't the first time something like this has happened. Evidence from both the genes of these children, and from an Ice Age cave, indicates that humanity may stand at the brink of a sudden "punctuation" in evolution. I'll warn you, this isn't my favorite Greg Bear book. Bear is a fine writer, but the characters here can sometimes be more than a little talky and passive. Though they are at the center of the action, they are more observers than drivers of the plot. Still, there are some terrific ideas here that make this book well worth reading.
Gattaca directed by Andrew Niccol
There are a lot of disturbing visions of the future out there in film land. You can turn to old faithfuls like 1984 or the post-apocalyptic horrors of The Road. But for my money, nothing terrifies like Gattaca. Why? Because not only do I believe this world is coming, I don't know how to stop it. When the doctor asks you if you'd like to make your child a little smarter, a little stronger, a little healthier and more attractive -- are you going to say no? Are you still going to say no when he tells you that all your neighbors are saying yes? Are you going to say no when he warns that your child will be at a disadvantage in school, in a career, in finding love? I'm not sure I could say no. This is a genie already thumping against the stopper, and once it's out of the bottle there's no going back.
Last and First Men by Olaf Stapledon
It's hard to think of a book that looks at human evolution across a broader sweep than Last and First Men. Late in the book, we've seen more than a dozen species of humanity branching into such diverse forms as humans with wings. And I'll give another warning -- if you read a book looking for sparkling characters and close interpersonal relationships, this isn't your book. This is a book written at a broad scale. Humanity is the central character, and the story can sometimes seem more appropriate to a documentary than a novel. It's also a bit dated scientifically (it was originally written in 1930), but most of what Stapledon wrote holds up surprisingly well. I have to admit that, I never got around to this book until a month ago -- specifically because it came up several times in comments here. If you can tolerate the unusual structure, you'll find an imagination set loose and story of immense sweep.
Maps by John Sladek
In the immortal words of Monty Python, "And now for something completely different." Sladek's brand of bottled insanity would be worth reading even if this uncollected collection didn't contain the story "Stop Evolution in It's Tracks!" Which is, actually, a story of an extremely colorful creationist. I can't do better than give you a short excerpt.
"Evolutionists will tell you how some little old amoeba evolved itself into some bigger bug, and how that evolved itself into a fish, and so on, right up the scale until the ape evolved itself into a man. But there's two things wrong with that cockeyed story.
"In the first place, the amoebas never evolved at all. They're still here! Speaking as a scientist, I can vouch for that! I have looked down a microscope myself and seen them. They look like this."
He showed a slide of blobs. "Still the same little critturs they was when Noah marched them aboard the ark, two by two."
When the murmurs of amazement had died down, he continued: "In the second place, apes could not evolve into humans for a very simple reason: There are no apes. The things we call apes in zoos are nothing but men dressed up in hairy suits. I myself have visited a theatrical costume place where they rent such costumes. There they are, hairy suits with nobody inside."
Honestly, even if you can resist the call of that doctor in Gattaca, can you say you don't want to hear the rest of the spiel from the Institute for Advanced Creationism?