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How to Build a Better Being By William Lee
In his 1871 treatise The Descent of Man, and Selection in Relation to Sex, Charles Darwin argued that although the concept of humans having evolved from a lower species was abhorrent to some, he personally “would as soon be descended from that heroic little monkey” as from the violent, savage early humans who undoubtedly were also part of our family tree. Given that sentiment, I’d like to believe that the father of evolutionary biology would look kindly upon the ungainly, mottled-brown creature that is prancing across my computer screen, screeching and chattering joyously with each step, and occasionally pausing to engage in a primitive ritualistic dance that vaguely resembles the Frug.
But Australopithie, as I call him, is not the mere product of random genetic mutations that allow him to adapt to the environment more effectively than his predecessors, as were the apelike ancestors whom Darwin was proud to claim as his own. To the contrary, I created him quite deliberately, with the help of Spore Creature Creator, a software program developed by game designer Will Wright, the auteur behind SimCity, The Sims and a new release, Spore, which simulates the evolutionary process. Creature Creator is a part of the new game. The program enables a player to assemble his or her own designer creature by picking various body parts and characteristics from menus, and then modifying them to suit. But behind the entertainment value, there’s actual science. As the National Geographic Channel documentary How to Build a Better Being details, Wright drew inspiration from the current state of knowledge in evolutionary developmental biology—or “Evo-Devo,” as scientists whimsically call it.
In particular, Creature Creator metaphorically embodies the concept that many very different types of creatures—from fruit flies and mice to elephants and humans--are created from essentially the same basic set of genes, employed in different ways. The key to diversity is a small fraction of the genome—eight so-called “toolkit genes”—that essentially tell thousands of other genes where to put various body parts on a developing embryo, and determine whether the end product is an insect or a person.
 EVOLUTIONARY DEVELOPMENT
Creature Creator also incorporates the related Evo Devo concepts of bilateral symmetry ? that is, that creatures are genetically hard-wired to have the same structures on both the left and right sides of the body ? and segmentation, with the body divided from top to bottom into zones with different functions. (As University of California-Berkeley geneticist Michael Levine explains in the documentary, when the toolkit genes malfunction, the result is a misshapen creature ? such as a fly with legs where its antennae should be.)
Of course, there are some significant differences between actual evolution and the computer-game version. In real life, species develop over long time spans--it took Homo sapiens, for example, millions of years to develop from earlier hominid creatures. Creature Creator, in contrast, is conveniently fast-paced — you can assemble a simulated animal in a matter of minutes. And unlike the real evolutionary drama, some of whose plot twists are dictated by chance mutations, Creature Creator allows you to choose whatever features for your creature that you like, based on utility or sheer whimsy. In that sense, arguably, the game comes closer to the non-scientific belief system of intelligent design.
STRANGE CREATURES
Endowing game players with such deity-like powers can lead to strange results. On YouTube, I am watching a video uploaded by a gamer named Bantexkaa, who recorded the entire process of creating a creature named Rhinoface. The latter is a dinosaur-like behemoth with an array of jagged spikes on his snout and spike-laden balls on his tail. He’s reacting to each stage of his own construction with burping-like noises. Initially, his hide is a brilliant electric blue — a not totally unrealistic choice, I must concede, since scientists believe that the giant reptiles may have been as brightly colored as modern lizards. But then, with a few more belches, he metamorphoses from blue to yellow and abruptly sprouts red stripes, which vanish briefly before again reappearing. Fully decorated, the creature now begins to dance in an awkward, tight-hipped waddle, like an offensive tackle at the prom. But he soon acquires an upgrade in physical grace, which he demonstrates by performing several back flips. Apparently, Rhinoface’s creator is pleased, because several miniature versions of the creature suddenly pop up on the screen. (In virtual evolution, cumbersome formalities such as mating and sexual reproduction are apparently unnecessary). Soon, the entire pack is prancing, flipping and squealing in unison. The Darwinian struggle has been transformed into Dancing With the Stars.
 CREATING A CREATURE
Now it’s my turn to create, but I’m not going to be as flamboyant as Bantexkaa. For one thing, my computer gaming skills, at least compared with those of my eight-year-old son, are stuck in the equivalent of the Middle Paleolithic period. Second, I’m too much of goal-oriented Type A personality. I’m going to attempt to build a basic human-like creature—or rather, to duplicate one that actually once existed on our planet. But I’m not aiming too high—no fully developed, versatile, ready-to-dominate clone of Cro-Magnon man for me. Instead, I’m aiming relatively low. I’m going to try to build a member of Australopithecus, the genus that’s widely interpreted as being ancestral to our genus, Homo. I thought about picking Australopithecus anamensis, the oldest member, which roamed in east Africa about four million years ago. Unfortunately, all that remains of his kind are jaws and teeth, a shinbone, a skeletal toe and a few other fragments that don’t give me enough to reassemble him. Instead, I’ll opt for Australopithecus afarensis, which came along about a million years later. One example of Australopithecus afarensis: Lucy, a celebrity among hominids, whose nearly complete skeleton was discovered in Ethiopia in 1974.
Australopithecus afarensis was around three-and-a-half to five feet tall and in the artist’s depiction that I find on the Web, it walked upright with a slight slouch, a little like a teenage slacker. Correspondingly, I give my creature a modest sized, gently rounded spinal column. I attach arms that are nearly as long as his legs, since the ratio of afarensis’s humerus to its femur was 95 percent, virtually the same as a modern chimpanzee. (The ratio in a modern human is around 70 percent.) The feet are another important detail. Australopithecus afarensis had adducted big toes aligned with the other toes like ours. Those weren’t as good as apelike opposable big toes for climbing trees, but were much better for bipedal walking. I chose the most human-like option available. Ditto for the hands, though in real life, Australopithecus afarensis’s hands were more primitive than ours. As Encyclopedia Britannica notes, it was capable of gripping sticks and stones firmly for throwing and pounding, but lacked a fully developed human power grip that would allow objects to be held between the partly-flexed fingers and the palm, with counter-pressure applied by the thumb. Finally, I pick a head that has a modest-sized mouth and teeth, since afarensis’ teeth were smaller than modern apes and closer in size and development to those of modern humans. There isn’t a lot of room for a human-sized brain, but that’s okay; afarensis had one the size of a chimpanzee, providing evidence that the development of bipedalism may have preceded brain expansion.
THE FINISHED CREATURE
When I am finished, Australopithie bears at least a vague resemblance to his pre-human evolutionary inspiration. He trots in small, bouncy steps around a grassy plain, making chattering noises and staring at the horizon of his simulated world with a wide-eyed look that I like to think approximates innocent wonder. Lest I feel too superior, I think back again to Charles Darwin. As the great scientist once wrote: “Man with all his noble qualities, with sympathy which feels for the most debased, with benevolence which extends not only to other men but to the humblest living creature, with his god-like intellect which has penetrated into the movements and constitution of the solar system - with all these exalted powers - Man still bears in his bodily frame the indelible stamp of his lowly origin.” I only wonder if my own distant ancestors could dance like this little guy can.
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