Man‑Made Evolution

Regardless of whether human biological evolution rolls on into the future or creeps to a halt, a new sort of evolution has come into being. Culture itself evolves. Languages evolve, airplanes evolve, music evolves, mathematics evolves, cooking evolves, even fashions in hats evolve. And the ways human creations change with time mirror biological evolution in uncanny ways. Languages branch into new ones much as animal species do: the longer a dialect is isolated from its mother tongue, the more distinct it becomes. Scientists can even chart the history of languages by drawing evolutionary trees, using the same methods they would use to chart the evolution of hominids.

One common feature of biological evolution is exaptation, in which an old structure gets borrowed to perform a new function–such as legs on a fish used to walk on land. Stephen Jay Gould points out that the same thing happens as technology evolves. In the markets of Nairobi, for example, you can buy sandals made out of automobile tires. “Tires make very good sandals,” Gould writes, “but one would never argue that Goodrich (or whoever) built the tires to provide footwear in Third World nations. Durability for sandals is a latent potential of auto tires, and the production of such sandals defines a quirky functional shift.”

Biological evolution and cultural evolution are just similar enough that scientists wonder if some of the same principles are at work in both of them. In his 1976 book The Selfish Gene, Richard Dawkins noted that our thoughts have surprisingly genelike properties. A song, for example, is a piece of information that is encoded in our brains, and when we sing it to others, it becomes encoded in theirs as well. It is as if we had sneezed and passed on a cold virus to them. Dawkins dubbed these virus‑like chunks of information “memes.” The same laws that govern the rise and fall of genes may apply to memes as well. Some genes are better at getting themselves replicated than others. A gene that makes a defective photoreceptor in the eye won’t spread as easily as one that lets its owner see. Likewise, some memes spread more easily than others, and a mutation to a meme may give it a competitive edge it lacked before.

In order to succeed, a meme doesn’t have to be superior in any intellectual sense to other memes. All it needs to do is get itself copied. One of Dawkins’ personal favorites is the Saint Jude letter, which promises good luck to its recipients if they send it to their friends. Saint Jude letters don’t make people win lotteries or get cured of cancer; they only manipulate people’s hopes to get themselves carried around the world. The Internet now surges with bad jokes and nude pictures of celebrities, passed on from one computer to another, thanks to the desires or boredom of Web surfers.

But there are many ways in which culture doesn’t evolve like viruses. People do not cause little mutations to an idea and then send these malformed notions out into the world to thrive or fail. They think things through hard; they jumble them up with other ideas into new fusions. Memes do not jump directly from one brain to another as DNA gets copied letter for letter from one generation to the next. People observe the actions of other people and try to imitate them, sometimes successfully, sometimes not.

In some ways cultural evolution is more Lamarckian than Darwinian. Lamarck thought that if a giraffe’s neck became longer during its life, it could pass on that long neck to its offspring. A father teaches his son how to make a sword, but in the son’s experience he may find a better way to apply the clay or fold the steel; he can then pass on a changed recipe to his own son.

Genes, it’s now becoming clear, do not always wait patiently for one generation to copy them into a new one. They have traveled across the tree of life many times, as viruses carry them to new species or as one organism devours another. Likewise, a piece of one culture can leap into another one and combine into something new. Witness Marco Polo bringing gunpowder to Europe, or African slaves bringing syncopated rhythm to the United States. The English in which I write these words is not a word‑for‑word descendant of the English that Chaucer spoke. It has been invaded by words from all over the world.

We live in symbiosis with our culture. The idea of a plow can survive only if there is a person thinking of it. And without plows, most humans would starve. For the most part, these technological inventions have served as extensions of our bodies. A spear lets a hunter kill an elk without claws or fangs. A windmill can grind seeds and grains far more effectively than our own teeth. Books are extensions of our brains, giving us a collective memory far more powerful than any one person can have.

In the 1940s, however, humans stumbled across a new form of culture: the computer. Computers are even more profound brain extensions than books. They can store information far more densely (compare the bound version of the Oxford English Dictionary filling a shelf to a single compact disk holding the same information). What’s more, computers are the first tools that can process information in the same basic ways a brain can, perceiving, analyzing, planning. Of course, the computer itself cannot do anything; it must be commandeered by programming code, much like cells are commandeered by their DNA.

In the 1950s only a fraction of a single megabyte of random‑access memory existed on the entire planet. Today a single cheap home computer may contain 50 megabytes, and it is no longer a lonely island of silicon: since the 1970s, the world’s computers have begun joining together as the World Wide Web has spread like a mesh of fungus threads. The Web is encircling Earth, subsuming not only computers but cars and cash registers and televisions. We have surrounded ourselves with a global brain, which taps into our own brains, an intellectual forest dependent on a hidden fungal network.

Computers can dutifully do the things we tell them to do. They can control the path of a spacecraft as it slingshots around the rings of Saturn. They can track the rise and fall of insulin in a diabetic’s body.

But it’s possible that once their global network becomes complex enough, it will spontaneously take on something like our own intelligence, perhaps even our own consciousness. Research on artificial life and evolutionary computing has already suggested that computers can evolve an intelligence that doesn’t resemble our own. If a computer is allowed to come up with its own ways to solve problems, it evolves solutions that may make no sense to our brains. There is no telling what the global web of computers may evolve into. In time, our culture may become an intimate stranger to us, a symbiotic brain. The lions on the walls of Chauvet will begin to dance.

Thirteen

What about God?

Elizabeth Steubing is a senior at Wheaton College in Illinois, a school whose motto is Christo et Regno Ejus (“For Christ and His Kingdom”). Steubing is a devout Christian herself and finds in her faith a deep reservoir of strength. “I think your worldview really does matter in where you’re going in life,” she says. “I want to become a doctor and help people. It’s not like you can’t do that without my worldview. But it just makes the picture so much bigger if I want to serve God and do what He wants with my life. It’s comforting too that I’m not just in it by myself.”

Steubing is also a Christian who asks a lot of questions, about troubling subjects like the existence of evil and the suffering of innocent people. “It’s very hard to explain away people’s pain, and I’ve thought a lot about that,” she says. “I have professors that I go to a lot and ask really tough questions, and they certainly don’t have all the answers either. But I love listening to what they have to say about it, because they’ve been on this road a lot longer than I have.”

Steubing grew up in Zambia before coming to the United States for high school. “We lived outside of town in the forest, and we just kept all sorts of pets like chameleons, bush babies, snakes, you name it. So we were always surrounded by nature.” At Wheaton she takes classes in biology, and her professors are teaching her about evolution. “I wouldn’t swear by it,” she says, “but I think it’s what fits the evidence better than any other theory that may be out there.”

Steubing knows that some of her fellow students at Wheaton object to being taught evolution, and that some parents won’t even send their children to Wheaton because of it. “I just can’t relate,” she says. “If it is an intellectual enterprise, I don’t want to hide from it just because some parts of it might pinch my theology.”

But Steubing is asking questions. What does evolution mean for her faith? On the one hand, she doesn’t feel that she has to deny evolution in order to be a Christian. “I think evolution as a process is fine. There’s a lot of evidence for it. But to say that it excludes God is pretty presumptuous. If God wants to work through His natural creation, I mean, what’s wrong with that? We would like to say that God works through material processes today in how He deals with us. Why can’t He have done that in the past?”

Steubing knows that some people have argued that there’s a conflict between the two. “If you extrapolate the evolutionary model to say that there is no other influence in how we came to be who we are, and it’s just strict natural selection, that does pose a problem for what it means to be human,” she says.

Ultimately, her questions about evolution boil down to one: “Where is God’s place if everything does have a natural cause?” she asks. “I’ve wrestled with that quite a bit.”

She is not alone.

Ever since the publication of Origin of Species, people have been pondering the significance of evolution for the meaning of their lives, and of life in general. Are we a biological accident or a cosmic imperative? For some people, the only way to deal with Steubing’s question has been to deny the evidence for evolution altogether. That was what Bishop Wilberforce did in 1860. And today a vocal opposition to Darwin remains in force, primarily in a country in which Darwin never set foot: the United States.