Evolution
“Darwin’s Devices”: Here come the robot fish
A scientist uses aquatic automatons to plumb the mysteries of evolution, intelligence and the future
A detail from the cover of "Darwin's Devices" Fish, without a doubt, gotta swim, but how do they do it? And how, over millenniums of evolution, did they get to be so good at it? These two questions have driven the career of John Long, a professor of biology and cognitive science at Vassar College. Long is so into fish that his primal scene of intellectual seduction involved a Ph.D. trying to get him to join her team by taking him out for coffee and asking, “Have you seen the vertebral column of a marlin?” Thus was Long launched into a course of study that would ultimately lead him to the improbable task of making robot fish.
As geeky as this may sound, it turns out that the problems inherent in making robot fish yield some of humanity’s deepest questions: How did we get here? What (and where) is thought? How much can we trust the symbols (words, images, digital signals) that dominate our lives? Long’s new book, “Darwin’s Devices: What Evolving Robots Can Teach Us About the History of Life and the Future of Technology,” is part Descartes, part MacGyver and part Douglas Adams, turning from rumination on the possibility of intelligence residing in a brainless body to tips on making artificial fish vertebrae out of coffee stirrers to the dopey yet endearing jokes that seem to flourish in laboratories all over the world.
Long works in a field called biorobotics, which builds physical devices to test hypotheses about animal behavior, rather than studying either the animal itself or digital models. Sometimes an animal can’t be studied for logistical reasons: marlins, for example, die in captivity and plesiosaurs are extinct. Computer models allow scientists to simulate complex, unreproducible conditions — say, the modeling of 10,000 generations of a particular organism — but as abstractions, they are prone to certain errors.
Robots, as Long explains, have their peculiar virtues. Long himself once created an impressive computer model illustrating how the marlin’s backbone helped the fish achieve its awe-inspiring swimming and leaping speeds, only to have a revered elder scientist note, “it appears to me that you’ve created a perpetual motion machine.” Robots, as Long points out, can’t violate the laws of physics. Instead of operating in a simulation of a physics-compliant environment, robots simply exist in the real universe, and must therefore play by the rules as a matter of course. At the same time, robots can be simplified to the degree that certain characteristics can be observed in isolation.
The main thing Long uses his robots to study is evolution. His first robot-fish experiment involved creating a bunch of large, tadpole-like “Evolvabots” designed to do one thing: swim toward a light source. With his team of students and fellow scientists — Long makes a point of mentioning the names of everyone who made significant contributions to his projects, a big departure from spotlight-hogging senior-scientist tradition — he rated their success at this imitation of “food-seeking” behavior. The robots (called Tadros) were given tails of varying degrees of stiffness and length and were then “mated” (algorithmically) over several generations to see if this would lead to selection for certain kinds of tails. The hypothesis Long and his colleagues wanted to test was that primeval invertebrates evolved backbones because it improved their ability to feed.
The experiment didn’t work out as they’d hoped, mostly because, in designing the experiment, the scientists had failed to fully appreciate a factor called wobble. One of the most intriguing and important aspects of “Darwin’s Devices” is the way it places the reader in the lab, at the shoulder of people doing hands-on science, sharing in their frustrations (over disappointing data, recalcitrant grant committees and astutely critical colleagues), their successes and their failures. And Long does this so lucidly that you find yourself caught up in the process, grasping the basics and eager to learn the results. It’s the best depiction of how science really works that I’ve ever read.
“Darwin’s Devices” could also administer a chastening rebuke to the many laypeople who talk and think sloppily about evolution. Determining exactly how growing a backbone helped ancient invertebrates thrive might seem superfluous to the quick-and-dirty school of cocktail-party Darwinism. Obviously, backbones helped because otherwise vertebrate animals would never have evolved. But as “Darwin’s Devices” illustrates, we can easily mistake the reasons for the evolution of certain traits by jumping to what seem like “logical” conclusions, and natural selection is not the only evolutionary pressure applied to a species. There are times when you just have to build something to understand how it works.
For example, the next type of robot Long and his colleagues developed they named Madeleine (because it is shaped, roughly, like the little French cakes). Madeleine had four paddles at each corner of its body, much like the extinct plesiosaur, a marine reptile. This creature was a tetrapod: a sea-dwelling animal descended from land-dwelling ancestors. Living aquatic tetrapods include whales, dolphins and sea otters, but “none of the living aquatic tetrapods ever use all four appendages to swim underwater — they only use two.” With Madeleine, the researchers hoped to figure out why this is so, since “it sure seemed like using four flippers for propulsion should be better in almost any way imaginable.”
It isn’t, actually, and that launched yet another branch of inquiry about why the plesiosaur used four flippers at all. If it’s that easy for legitimate scientists to be mistaken about something as seemingly simple as four-flippered locomotion, you can see why so many of them regard popular but highly speculative pastimes like evolutionary psychology as pseudoscience.
One party who has found the activities of Long and his robotics lab keenly interesting is the U.S. government. It’s not a big leap from “robot fish” to the notion of defense applications, and Long, despite a youthful infatuation with all things military, finds this troubling. But not that troubling! After a bit of hemming and hawing about it — noting that, if over 50 nations are pursuing military robot research, then American scientists can’t afford to opt out — he plunges into rampant (and, I must say, fascinating) theorizing about what sorts of robots would work best in battle. They need to be complex enough to cope with contingencies, but simple (i.e., cheap) enough that commanders aren’t afraid to burn through them.
Long ends with these cautionary words: “The reality is that evolving robots are and will be created for academic, industrial and military purposes. This means that we should all become students of robots of any kind, whether they be evolving robots, nonevolving autonomous robots, or semiautonomous and remotely controlled military robots. We need to understand robots so we can proceed with due caution and deliberation.” Yikes! And probably true. “Darwin’s Devices” will get some of us, at least, a little closer.
Laura Miller is a senior writer for Salon. She is the author of "The Magician's Book: A Skeptic's Adventures in Narnia" and has a Web site, magiciansbook.com. More Laura Miller.
Miss USA contestants: Unevolved?
The contestants were asked whether evolution should be taught in schools. Here are our winners and losers
The Miss USA pageant crowned its annual winner on Sunday, but the contest is drawing new attention for a video of all 51 contestants wrestling with the question, “Should evolution be taught in schools?” The results, as you might expect, are all over the place. To wit: While only a couple said a definitive “no,” dozens more squirmed through answers — trying as hard as possible not to offend anyone — before arriving at the common conclusion that evolution should be taught alongside “alternative beliefs.”
Continue Reading CloseTime-travel sex: Bad for sea monkeys
Study shows female brine shrimp survive longer when they don't mate with "males from the future or the past"
For a new study set to be published in the journal Evolution, scientists from the Center for Functional and Evolutionary Ecology in Montpellier, France, mated female brine shrimp (“sea monkeys”) with males from past and future generations.
The report, called “Male-Female Coevolution in the Wild: Evidence from a Time Series in Artemia Franciscana,” found that the female brine shrimp “survived better and had longer interbrood intervals when mated with their contemporary males compared to when mated with males from the future or the past.” Its formal conclusion: “[T]he process of male-female coevolution, previously revealed by experimental evolution in laboratory artificial conditions, can occur in nature on a short evolutionary time scale.”
Continue Reading CloseEmma Mustich is a Salon contributor. Follow her on Twitter: @emustich. More Emma Mustich.
Five signs your Republican governor wants to be president
Did he suddenly express doubts about evolution or develop an interest in bombing foreign countries? Watch out
Chris Christie and Jon Huntsman Chris Christie, a wealthy, well-educated lawyer from New Jersey, is suddenly not willing to say whether or not he believes in biological evolution. Christie went to a very good public high school and he’s a mainstream American Catholic, not an evangelical Protestant, so I am going to guess that he does believe in evolution, if he ever even gives the idiotic question any thought. I’d also guess that believing in evolution is not particularly controversial among New Jersey Republicans, who are not exactly Kansas Republicans.
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Alex Pareene writes about politics for Salon and is the author of "The Rude Guide to Mitt." Email him at apareene@salon.com and follow him on Twitter @pareene More Alex Pareene.
The science of the smooch
Why mash our mouths together? An expert explains the evolutionary reasons for kissing, and why men like more tongue
close up portrait of young caucasian couple kissing(Credit: Serg Zastavkin) Let’s be honest, a kiss is never just a kiss. It is the ultimate romantic symbol in our culture — from Shakespearean tragedies to Gustav Klimt’s gilded embrace to the legendary V-J Day smooch in Times Square to those critical words “you may kiss the bride.” Sometimes it’s instead an expression of affection, elation, loyalty or, on the other hand, disloyalty (see: the kiss of Judas). In cruder manifestations — take Britney and Madonna’s lip smacking, and the tonsil hockey of modern reality television — it’s a way to scandalize. But despite this breadth of meaning, we have very rigid ideas of what types of kissing are appropriate and acceptable — as Stephanie Seymour recently discovered after photos circulated of an ocean-side embrace with her son.
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Tracy Clark-Flory is a staff writer at Salon. Follow @tracyclarkflory on Twitter. More Tracy Clark-Flory.
Crazy Alabama attack ads just keep getting better
A new commercial smears Bradley Byrne for (gasp!) supporting evolution. And guess who helped pay for it?
Attack ad aimed at gubernatorial candidate Bradley Byrne The outcome of Alabama’s gubernatorial race is still up in the air, but the contest itself is shaping up to be the most entertaining show on TV. Last month, candidate Tim James explained that this is the state where “we speak English.” Now, a new campaign ad takes Republican candidate Bradley Byrne to task because “on the school board Byrne supported teaching evolution, said evolution best explains the origin of life – even recently said the Bible is only partially true.” This news, by the way, is delivered in an incredulous, “Can you believe this guy?” tone.
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Mary Elizabeth Williams is a staff writer for Salon and the author of "Gimme Shelter: My Three Years Searching for the American Dream." Follow her on Twitter: @embeedub. More Mary Elizabeth Williams.
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