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Fishing Blues

Without limits on industrial-scale catches, marine populations will continue to collapse

 

If there is any benefit to be salvaged from the disastrous overfishing of the bluefin tuna (see “The Bluefin in Peril,” by Richard Ellis), it’s the spotlight that it shines on the plundering of the world’s marine life. It has been 16 years since  the demand for cod led to the collapse of the once superabundant cod fisheries in the North Atlantic off Newfoundland. Disappearing with them were some 40,000 jobs. Seafood Watch, an online information clearinghouse run by the Monterey Bay Aquarium in California, has placed all Atlantic populations of flatfish, including flounder, halibut, plaice and sole, on a list of fishes that it urges consumers to avoid. The list goes on.

You can’t entirely blame the fishers. Yes, a lot of pirates are out there, taking fish illegally, underreporting their catches, fishing under the flags of countries not party to international fishing agreements. But for many cultures, fishing is a way of life—and sadly, because of overfishing, a hard way to carry on. The lure of dollars—or euros or yen—becomes all but irresistible when the alternatives become ever more limited. As Ellis reports, a single bluefin tuna fetched $173,600 in Tokyo, and prices of a sushi dinner for two in New York City can reach $1,000.

With that kind of money at stake, it is hardly surprising that industrial-scale technology has caught on, big time. Hooks are paid out on “long-lines” more than 50 miles in length. Factory ships that can hold 1,000 tons of fish store and process the catches. Fishing on such a massive scale can quickly exhaust a fishing ground, but when that happens, the factory ships just move on. As a result, fisheries themselves are becoming ever more remote.

The bottom of what is known as the continental slope, between 600 and 6,000 feet deep, is home to several species that swim in schools and grow as long as two to three feet. Their presence opened up the continental slope to industrial deep-sea fishing that pays off handsomely. The usual method, known as bottom trawling, is to drag a large cone-shaped net, weighted with 15 tons of gear, across the seabed. The net catches everything in its path, and the gear crushes any 1,000-year-old coral that stands in its way.

What are the environmental costs? No one really knows—and that is part of the problem. According to Richard L. Haedrich, an ichthyologist writing in a recent issue of Natural History, catch quotas for deep-sea fishes were set “essentially by guesswork, relying on ... knowledge of shallow-water species. They took no account of the far slower turnover rates in a typical population of deep-sea fishes.” The predictable result is that two deep-sea species have already been depleted: the orange roughy, formerly known as the slimehead, and the Chilean sea bass, aka Patagonian or Antarctic toothfish. When they’re gone, Big Fishing will pack up and move on once again.

What is to be done? Biologists must have the chance to study fish populations before sustainability levels are set and fish are taken. Laws, treaties, police work and stiff penalties are essential to curb the pirates and keep honest fishers in business. But market forces are ultimately to blame, and market forces will determine the outcome. Consumers who vote with their pocketbooks can turn the tide of demand.

The first step is finding out what is safe to buy. Numerous Internet sites such as Seafood Watch, mentioned earlier, give basic information about the sustainability of various marine populations. The second step is determining the provenance of a fish on the market: Where does it come from, and how can you know the information is reliable? The provenance system is already in place for wine and in some countries for beef. A similar system of tracking fish from catch to consumer could drive down demand, and hence price, for endangered, uncertified products.

With provenance determined, fish lovers could harness the power of the Internet. Does a restaurant or supermarket persist in selling “red card” fish? A comment in an online review might get results. Publicity and shame are powerful tools, not to be used lightly or without warning. But those who knowingly trade in fish that are demonstrably at risk lose their right to be ignored.

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Human Embryonic Stem Cells Fix Stroke-Afflicted Rats

Treatment strengthened weak paws without causing cancer

 
DIFFERENT STROKES: Rats given neural tissue derived from human embryonic stem cells were able to recover from an induced stroke that hampered their exploration of a tube in the lab. It ought to work for cardboard tubes, too.

In a new study, rats were spared the limb-weakening effects of a stroke if they were treated with brain tissue cultivated from human embryonic stem cells. But unlike similar experiments, the transplanted cells gave no sign of causing tumors, according to a report this week in the online journal PLoS One.

Researchers say that if they can build a string of such successes in a range of animal models, they can make a stronger case for testing the cells in people. "This is really exciting, just to overcome this obstacle of tumorigenicity," says Stanford University stem cell biologist Marcel Daadi, a co-author of the study.

Investigators have had success of late creating stem cells, or cells very similar to them, from new sources such as adult human tissue. But the ongoing scientific challenge is to harness those cells' ability to morph into the different adult cell types and thereby develop new treatments for debilitating diseases such as stroke, which strikes about 700,000 Americans every year, according to the U.S. Centers for Disease Control and Prevention.

Daadi and his colleagues transplanted specially grown human neural stem cells—precursors of neurons and other neural cell types—into the brains of rats made to suffer a stroke in the right hemisphere of the brain, which had sapped the strength from their front left paws. Rats that received the transplant recovered strength in the impaired limbs, as judged by a test in which the rodents explore a tube. Animals given a sham injection regained little or none of the lost strength, the group reports.

The researchers found no sign of tumor growth in the brains of the healed rats or after stem cell injections into the bodies of healthy rats. Daadi attributes the success to their way of harvesting neural stem cells from human embryonic stem cells, which he says weeded out unwanted cell types that might grow into tumors.

An application for early human testing of a stroke treatment using cells derived from human fetal brain tissue, developed by the Guildford, England–based stem cell company ReNeuron Group, PLC, is currently on hold with the Food and Drug Administration, pending additional data.

Humans Marrying Robots?

Is love and marriage with robots an institute you can disparage? Not to computer pioneer David Levy. Continuing advances in computers and robotics, he thinks, will make legal marriages between Homo and Robo feasible by mid-century

 

Last year, David Levy published a book, Love and Sex with Robots, which marked a culmination of years of research about the interactions between humans and computers. His basic idea is that, for humans who cannot establish emotional or sexual connections with other people, they might form them with robots. The topic is ripe for ridicule: On The Colbert Report in January, host Stephen Colbert asked Levy, "Are these people who can't establish relationships with other human beings, are they by any chance people who write about love and sex with robots?" The 62-year-old Levy, though, is quite serious, as he explains to frequent contributor Charles Q. Choi in the Insights story "Not Tonight, Dear, I Have to Reboot," appearing in the March issue of Scientific American. Here is an expanded interview.

How did you first become interested in artificial intelligence (AI)?
Everything happened almost by accident. I learned to play chess by eight—it was my big passion in high school and university. In my last year at university, I came across a thing called a computer. I heard about it, but knew nothing about it. They were incredibly primitive then—they didn't run on transistors, but on vacuum tubes. I got interested in computer programming through programming games. Then I head about a subject called AI, which people in Edinburgh were working on, such as Donald Michie, the head of the department of machine intelligence at the University of Edinburgh, who worked with Alan Turing on breaking German codes. Donald Michie was an amazing guy who was killed just recently in a car crash. He was the founding father of AI in the U.K. and introduced me and others to AI.

So your interest in chess programs led you to computers and, ultimately, artificial intelligence?
Back then, people wrote chess programs to simulate human thought processes. It turned out in time that approach didn't work, that chess programs would use completely different techniques that are not humanlike at all. But I was still left interested in simulating human thought processes and emotions and personality. I thought, "Wouldn't it be interesting if there were artificial people we could talk to?" So that started me thinking even more about the way humans interact with computers—not just by typing on a keyboard, but how people could interact with computers in a humanlike way. I funded a project for three years that won the Loebner Prize in 1997, a world championship for conversational computer programs decided by a Turing test–type conversation.

In other words, the program's responses tried as much as possible to be indistinguishable from those of a human, and in Turing's conception, the machine could be said to think. So, moving on from mere conversation, you began researching how, um, far interaction between humans and robots could go?
Around the year 2003, I started researching this topic very seriously. I was writing a book, Robots Unlimited, with a couple of chapters on robot emotion—love, even sex. I found so much material that when I finished that book, I wanted to look even more deeply in human emotional relationships with computers, with the possibility of sexual relations. I decided to call the book I wrote Love and Sex with Robots.

Did any of the research you found prove especially memorable?
The one single thing that made me go into this subject deeply was when I read a book by Sherry Turkle, The Second Self. In there, she wrote about some students she interviewed in her attempts to figure out how people related to computers. In one anecdote with a student dubbed "Anthony," he tried having girlfriends but preferred relationships with computers. With girls, he wasn't sure how to react; but with computers, he knew how to react. I thought that was so fascinating. And there are loads of Anthonys out there who find it difficult to, or can't form satisfying relationships with, humans. I dedicated my book Love and Sex with Robots to Anthony and all the other Anthonys before and since of both sexes—to all those who feel lost and hopeless without relationships, to let them know there will come a time when they can form relationships with robots.

So what was it like researching the possibility of sex with robots? You ended up writing a lot about sex dolls—did you know about sex dolls before you wrote your book?
I hadn't thought about them beforehand at all. It was absolutely fascinating doing the research. Then I got the idea that sex with dolls is like sex with prostitutes—you know the prostitute doesn't love you and care for you, is only interested in the size of your wallet. So I think robots can simulate love, but even if they can't, so what? People pay prostitutes millions and millions for regular services. I thought prostitution was a very good analogy.

And, as you mention in Love and Sex with Robots, brothels in Japan and South Korea already offer sex with dolls for the same rates they would charge for human prostitutes. So in studying sex with prostitutes, you figured you might begin to understand what the thinking behind sex with robots would be.
I started analyzing the psychology of clients of prostitutes. One of the most common reasons people pay for sex was that people wanted variety in sex partners. And with robots, you could have a blonde robot today or a brunette or a redhead. Or people want different sexual experiences. Or they don't want to commit to a relationship, but just to have a sexual relationship bound in time. All those reasons that people want to have sex with prostitutes could also apply to sex with robots.

But sex with robots won't just be a guy thing?
When I started, the research was almost entirely on male clients, but the number of women who pay for sex is on the increase, although there's not much published on the subject. That shows both sexes are interested and willing and desirous to get sex they paid for. Heidi Fleiss is proposing to open a brothel in Nevada where all the sex workers are male and the clients are female. You already have something similar in Spain.

If people fall in love with robots, aren't they just falling in love with an algorithm?
It's not that people will fall in love with an algorithm, but that people will fall in love with a convincing simulation of a human being, and convincing simulations can have a remarkable effect on people.

When I was 10, I was in Madame Tussauds waxworks in London with my aunt. I wanted to find someone to get to some part of the exhibition and I saw someone, and it didn't dawn on me for a few seconds that that person was a waxwork. It had a profound effect on me—that not everything is as it seems, and that simulations can be very convincing. And that was just a simple waxwork.

And if you or others could be taken in just by a wax figure, even for a moment, imagine what a realistic robotic simulation of a person would do. But if people are aware that a robot's just electronics, won't that be an obstacle to true love?
By 40 or 50 years, everyone of a marriageable age will have grown up with electronics all around them at home, and not see them as abnormal. People who grow up with all sorts of electronic gizmos will find android robots to be fairly normal as friends, partners, lovers.

Now did science fiction inspire you at all? Because science fiction is naturally one of the first things that leapt to my mind when I think of a society with robots in it.
I don't read science fiction at all. The only sci-fi book I ever read was as a favor to a publisher who wanted a quote from me on the back cover, but the book was so dreadful that I couldn't support it.

Are advances in robotics really going to happen that fast? Wouldn't the technology take up rooms of electronics?
Computer technology is getting faster and more powerful and smaller all the time. What fits in a backpack now could fit in a matchbook in 30 years' time.

If we don't yet completely understand humans, how can we make a humanlike robot?
It will be an iterative process, to be sure. But while we don't understand humans perfectly, we know quite a bit now about human behavior and psychology, and we could program that in.

Isn't your prediction about humans marrying robots in 50 years optimistic?
If you went back 100 years, if you proposed the idea that men would be marrying men, you'd be locked up in the loony bin. And it was only in the second half of the 20th century that you had the U.S. federal government repealing laws in about 12 states that said marriage across racial boundaries was illegal. That's how much the nature of marriage has changed.

I think the nature of marriage in the future is that it will be what we want it to be. If you and your partner decide to be married, you decide what the bounds are, what its purpose is to you.

Would people really want a robot that agreed with everything you wanted or were completely predictable?
I do think there is often a need for friction in relationships. You wouldn't actually want a robot that does everything you want. Most people might want robots that sometimes say, "I don't really want to do that," that rejects certain requests from time to time. So you could program that in, the level of disagreement you want.

And you could program a robot to have different tastes from you. I personally find it very beneficial that my wife has interests that I do not. You could find it fascinating, for instance, that your robot knows a lot about 19th-century South African stamps or the like.

How might human–robot relationships alter human society?
I don't think the advent of emotional and sexual relationships with robots with end or damage human–human relationships. People will still love people and have sex with people. But I think there are people who feel a void in their emotional and sex lives for any number of reasons who could benefit from robots. Other people might try out a relationship with a robot out of curiosity, or be fascinated by what's written in the media. And there are always people who want to keep up with the neighbors.

One point a friend made to me was that there will be people who say, "Oh, you're only a robot." But I also think there will be people who take the view, "Oh, you're only a human."

Isn't falling in love with a robot reminiscent of falling in love in a chat room?
I think it's a very small step at the end of the day—if you are sitting at home talking in a chat room with someone who purports to be a 26-year-old female—between that person being a human or a robot. It's a kind of Turing test. So many people nowadays are developing strong emotional attachments across the Internet, even agreeing to marry, that I think it doesn't matter what's on the other end of the line. It just matters what you experience and perceive.

Do you think others will follow this field?
I was actually recently contacted by a woman at the University of Washington, who wants to write a thesis on human–robot relationships.

What directions will you pursue now?
I'm writing an academic paper on the ethical treatment of robots. Not just the ethics of designing robots to do certain things—people write about whether we should design robots to go into combat and kill people, for instance—but should we be treating robots in an ethical way. If we treat robots in an unethical way, would that be a very bad lesson for other people and children? If it's seen as okay to maltreat robots, would that send a message about living creatures? Robots can certainly have a semblance of being alive.

What does your wife think?
She has a different slant from me. She's not a science person at all—her background's in English and drama; she's not interested in computers or robots or AI. She was totally skeptical of the idea that humans would fall in love with robots. She's still fairly skeptical, but she's beginning to appreciate something like this will happen.

What happens if 50 years from now your predictions have not proved true, and humans and robots don't marry?
I know some people think the idea is totally outlandish. But I am totally convinced it's inevitable. I would be absolutely astounded if I'm proven wrong—not if I'm a few years off, but if I'm proven completely wrong.

How Ancient Trade Changed the World

You've got the gold I need for my necklace and I've got the silk you need for your robe.

What to do?

Nowadays, if you need something, you go to the closest mall, shell out a few bucks and head home. Thousands of years ago, the process wasn't nearly as simple. If you or someone in your town didn't grow it, herd it or make it, you needed to abandon that desire or else travel for it, sometimes over great distances. For many towns, the effort of trade was too much. Those ancient towns make only rare appearances in our history books.

When the first civilizations did begin trading with each other about five thousand years ago, however, many of them got rich...and fast.

Trade was also a boon for human interaction, bringing cross-cultural contact to a whole new level.

Luxury goods

When people first settled down into larger towns in Mesopotamia and Egypt, self-sufficiency – the idea that you had to produce absolutely everything that you wanted or needed – started to fade. A farmer could now trade grain for meat, or milk for a pot, at the local market, which was seldom too far away.

Cities started to work the same way, realizing that they could acquire goods they didn't have at hand from other cities far away, where the climate and natural resources produced different things. This longer-distance trade was slow and often dangerous, but was lucrative for the middlemen willing to make the journey.

The first long-distance trade occurred between Mesopotamia and the Indus Valley in Pakistan around 3000 BC, historians believe. Long-distance trade in these early times was limited almost exclusively to luxury goods like spices, textiles and precious metals. Cities that were rich in these commodities became financially rich, too, satiating the appetites of other surrounding regions for jewelry, fancy robes and imported delicacies.

It wasn't long after that trade networks crisscrossed the entire Eurasian continent, inextricably linking cultures for the first time in history.

By the second millennium BC, former backwater island Cyprus had become a major Mediterranean player by ferrying its vast copper resources to the Near East and Egypt, regions wealthy due to their own natural resources such as papyrus and wool. Phoenicia, famous for its seafaring expertise, hawked its valuable cedar wood and linens dyes all over the Mediterranean. China prospered by trading jade, spices and later, silk. Britain shared its abundance of tin.

Pit stops

In the absence of proper roads, the most efficient way to transport goods from one place to another was by sea.

The first and most extensive trade networks were actually waterways like the Nile, the Tigris and the Euphrates in present-day Iraq and the Yellow River in China. Cities grew up in the fertile basins on the borders of those rivers and then expanded by using their watery highways to import and export goods.

The domestication of camels around 1000 BC helped encourage trade routes over land, called caravans, and linked India with the Mediterranean. Like an ancient version of the Wild West frontier, towns began sprouting up like never before anywhere that a pit-stop or caravan-to-ship port was necessary. Many of the better-known satellite towns of Rome and Greece were founded this way, stretching those fabled empires further afield until their influences crossed continents.

And in each of these places, foreign traders drank in port towns and shared stories and customs from back home, leaving more than just their parcels behind. 

Scaled-Down Solar System Found 5,000 Light-Years Away

Smaller versions of Jupiter and Saturn may be the first of many

planetary system 
TO SCALE: A new planetary system contains two planets that closely resemble Jupiter and Saturn in their relative mass and distance to their star.

Astronomers have discovered a pair of planets around a star 5,000 light-years away that resemble smaller versions of Jupiter and Saturn, hinting that solar systems like ours may be unexpectedly common. As in our own solar system, the closer of the two planets to their star is the larger one, 70 percent as massive as Jupiter; the more distant planet has 90 percent the mass of Saturn.

The star itself, dubbed OGLE-2006-BLG-109L, is dimmer than our sun and is only half its size. But the ratios between the two planets' masses and that of their star as well as their relative orbital distances are very similar to those of Jupiter and Saturn. "Basically what we found is a scaled-down analog of our solar system," says Scott Gaudi, an assistant professor of astronomy at The Ohio State University and lead author of the study published this week in Science.

Gaudi and his colleagues discovered the planets over a two-week period in early spring 2006, when their stellar parent crossed in front of a more distant star. Due to an effect called gravitational microlensing, the gravity of the nearer star magnified the light 500-fold from the more distant one. The motions of the planets caused periodic spikes in the brightness of the magnified light, which allowed the team to calculate the size of the planets and their distances from the star. The Optical Gravitational Lensing Experiment (OGLE) at the Las Campanas Observatory in Chile first detected the event.

Researchers know of other multiplanet systems, but in those systems the planets are huddled close to their stars. Microlensing events reveal planets in orbits that are more distant from their stars.

Previous to this discovery, microlensing had turned up four planets, two of them
Jupiter-size. But this crossing was the first one that happened to have the right conditions to reveal the presence of smaller planets. "The first time we could find a Jupiter-–Saturn analogue, we did," Gaudis says. "And that provides us a hint ... that these kind of solar system analogues might be quite common."

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