“Darwin’s Devices”: Here come the robot fish

A scientist uses aquatic automatons to plumb the mysteries of evolution, intelligence and the future

Topics: What to Read, Books, Charles Darwin, Biotechnology, Science, Evolution, Editor's Picks,

"Darwin's Devices": Here come the robot fishA 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

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.

Featured Slide Shows

  • Share on Twitter
  • Share on Facebook
  • 1 of 7
  • Close
  • Fullscreen
  • Thumbnails
    AP/Jae C. Hong

    Your summer in extreme weather

    California drought

    Since May, California has faced a historic drought, resulting in the loss of 63 trillion gallons of water. 95.4 percent of the state is now experiencing "severe" drought conditions, which is only a marginal improvement from 97.5 percent last week.

    A recent study published in the journal Science found that the Earth has actually risen about 0.16 inches in the past 18 months because of the extreme loss of groundwater. The drought is particularly devastating for California's enormous agriculture industry and will cost the state $2.2 billion this year, cutting over 17,000 jobs in the process.

       

    Meteorologists blame the drought on a large zone (almost 4 miles high and 2,000 miles long) of high pressure in the atmosphere off the West Coast which blocks Pacific winter storms from reaching land. High pressure zones come and go, but this one has been stationary since December 2012.

    Darin Epperly

    Your summer in extreme weather

    Great Plains tornadoes

    From June 16-18 this year, the Midwest was slammed by a series of four tornadoes, all ranking as category EF4--meaning the winds reached up to 200 miles per hour. An unlucky town called Pilger in Nebraska was hit especially hard, suffering through twin tornadoes, an extreme event that may only occur every few decades. The two that swept through the town killed two people, injured 16 and demolished as many as 50 homes.   

    "It was terribly wide," local resident Marianne Pesotta said to CNN affiliate KETV-TV. "I drove east [to escape]. I could see how bad it was. I had to get out of there."   

    But atmospheric scientist Jeff Weber cautions against connecting these events with climate change. "This is not a climate signal," he said in an interview with NBC News. "This is a meteorological signal."

    AP/Detroit News, David Coates

    Your summer in extreme weather

    Michigan flooding

    On Aug. 11, Detroit's wettest day in 89 years -- with rainfall at 4.57 inches -- resulted in the flooding of at least five major freeways, leading to three deaths, more than 1,000 cars being abandoned on the road and thousands of ruined basements. Gov. Rick Snyder declared it a disaster. It took officials two full days to clear the roads. Weeks later, FEMA is finally set to begin assessing damage.   

    Heavy rainfall events are becoming more and more common, and some scientists have attributed the trend to climate change, since the atmosphere can hold more moisture at higher temperatures. Mashable's Andrew Freedman wrote on the increasing incidence of this type of weather: "This means that storms, from localized thunderstorms to massive hurricanes, have more energy to work with, and are able to wring out greater amounts of rain or snow in heavy bursts. In general, more precipitation is now coming in shorter, heavier bursts compared to a few decades ago, and this is putting strain on urban infrastructure such as sewer systems that are unable to handle such sudden influxes of water."

    AP/The Fresno Bee, Eric Paul Zamora

    Your summer in extreme weather

    Yosemite wildfires

    An extreme wildfire burning near Yosemite National Park forced authorities to evacuate 13,000 nearby residents, while the Madera County sheriff declared a local emergency. The summer has been marked by several wildfires due to California's extreme drought, which causes vegetation to become perfect kindling.   

    Surprisingly, however, firefighters have done an admirable job containing the blazes. According to the L.A. Times, firefighters with the state's Department of Forestry and Fire Protection have fought over 4,000 fires so far in 2014 -- an increase of over 500 fires from the same time in 2013.

    Reuters/Eugene Tanner

    Your summer in extreme weather

    Hawaii hurricanes

    Hurricane Iselle was set to be the first hurricane to make landfall in Hawaii in 22 years. It was downgraded to a tropical storm and didn't end up being nearly as disastrous as it could have been, but it still managed to essentially shut down the entire state for a day, as businesses and residents hunkered down in preparation, with many boarding up their windows to guard against strong gusts. The storm resulted in downed trees, 21,000 people out of power and a number of damaged homes.

    Debbie Arita, a local from the Big Island described her experience: "We could hear the wind howling through the doors. The light poles in the parking lot were bobbing up and down with all the wind and rain."

    Reuters/NASA

    Your summer in extreme weather

    Florida red tide

    A major red tide bloom can reach more than 100 miles along the coast and around 30 miles offshore. Although you can't really see it in the above photo, the effects are devastating for wildlife. This summer, Florida was hit by an enormous, lingering red tide, also known as a harmful algae bloom (HAB), which occurs when algae grow out of control. HABs are toxic to fish, crabs, octopuses and other sea creatures, and this one resulted in the death of thousands of fish. When the HAB gets close enough to shore, it can also have an effect on air quality, making it harder for people to breathe.   

    The HAB is currently closest to land near Pinellas County in the Gulf of Mexico, where it is 5-10 miles offshore.

  • Recent Slide Shows

Comments

0 Comments

Comment Preview

Your name will appear as username ( settings | log out )

You may use these HTML tags and attributes: <a href=""> <b> <em> <strong> <i> <blockquote>