martes, 15 de febrero de 2011
To Talk With Aliens, Learn to Speak With Dolphins
Early in February, the Kepler Space Telescope announced a new bonanza of distant planets, reconfirming that solar systems, possibly hosting life, are common in the universe.
So if humanity someday arrives at an extraterrestrial cocktail party, will we be ready to mingle? At the Wild Dolphin Project in Jupiter, Fla., researchers practice for contact by trying to talk with dolphins.
More than two decades ago, behavioral biologist Denise Herzing started studying free-ranging spotted dolphins in the Bahamas. Over the years, she noticed some dolphins seeking human company, seemingly out of curiosity.
“We thought, ‘This is fascinating, let’s see if we can take it further,’” Herzing said. “Many studies communicate with dolphins, especially in captivity, using fish as a reward. But it’s rare to ask dolphins to communicate with us.”
Dolphins have large, sophisticated brains, elaborately developed in the areas linked to higher-order thinking. They have a complex social structure, form alliances, share duties and display personalities. Put a mirror in their tank and they can recognize themselves, indicating a sense of self.
When trained, they have a remarkable capacity to pick up language. At the Dolphin Institute in Hawaii, Louis Herman and his team taught dolphins hundreds of words using gestures and symbols. Dolphins, they found, could understand the difference between statements and questions, concepts like “none” or “absent” and that changing word order changes the meaning of a sentence, essentially, they get syntax.
Easier language through math
Laurance Doyle of the SETI Institute in Mountain View, Calif. also studies animal communication in preparation for extraterrestrial contact. Doyle uses information theory — a branch of math that analyzes the structure and relationships of information — to analyze radio signals, hoping to better detect intelligence in space.
“Information theory is an example of an intelligence filter we can use to sift the signals we get from space,” Doyle said. “Otherwise, we might miss them.”
Using information theory it’s possible to separate binary code from random zeros and ones, for examples. By analyzing dolphin sounds, it’s possible to know that adults send information when they whistle, but not babies. Like human babies, they just babble until they’ve learned language. Information theory also shows that humpback whales have rules of grammar and syntax.
“At SETI meetings we always ask ‘Are we alone?’” Doyle said. “No, we’re not alone. There are many animals communicating right here that we don’t understand.”
Doyle is interested in applying information theory to bees. Social bees are capable of complex group decisions, it seems, but their intelligence is a product of the hive. He also plans to study the communication between trees, because they share information about pests and threats via chemicals.
“Who knows? Brains might not be necessary,” Doyle said.
Some tantalizing studies even suggest dolphins share their own language (see sidebar). All are qualities we’d hope to see in an alien, and no daydream of contact is complete without some attempt at communication. Yet with dolphins, our attempts have involved teaching them to speak our language, rather than meeting in the middle.
Herzing created an open-ended framework for communication, using sounds, symbols and props to interact with the dolphins. The goal was to create a shared, primitive language that would allow dolphins and humans to ask for props, such as balls or scarves.
Divers demonstrated the system by pressing keys on a large submerged keyboard. Other humans would throw them the corresponding prop. In addition to being labeled with a symbol, each key was paired with a whistle that dolphins could mimic. A dolphin could ask for a toy either by pushing the key with her nose, or whistling.
Herzing’s study is the first of its kind. No one has tried to establish two-way communication in the wild.
“This is an authentic way to approach this, she’s not imposing herself on them,” said Lori Marino, the Emory University biologist who, with Hunter College psychologist Diana Reiss, pioneered dolphin self-recognition studies. “She’s cultivated a relationship with these dolphins over a very long time and it’s entirely on their terms. I think this is the future of working with dolphins.”
For each session, the researchers played with the dolphins for about half an hour, for a total of roughly 40 hours over the course of three years. They reported their findings of this pilot study in the December issue of Acta Astronautica.
Herzing’s team found that six dolphins, all young females, were interested in the game, and would come to play when the game was on. Young males were typically less social and less interested in humans. “This is when the females have a lot of play time,” Herzing said, “before they are busy being mothers.”
To Herzing’s surprise, some of her spotted dolphins recruited bottlenose dolphins, another species, to the game. This shows their natural curiosity, Herzog zaid. In the wild, dolphins communicate across cetacean species lines, coordinating hunting with other dolphins and even sharing babysitting duties.
Herzing found the study sessions were most successful when, before playing, the humans and dolphins swam together slowly and in synchrony, mimicked each other and made eye contact. These are signs of good etiquette among dolphins. Humans also signal their interest in someone with eye contact and similar body language. Perhaps these are universal — and extraterrestrial — signs of good manners.
Before we hope to understand extraterrestrials, we should probably practice with smart animals right here on Earth. Astronomer Laurance Doyle of the SETI Institute was struck by this thought at a recent conference.
“From the way the presenter was speaking, I thought he was going to announce that he had found a signal of extra terrestrial intelligence,” Doyle said. “We’ve been waiting for this for years, but I thought, ‘We’re not ready!’ We can’t even speak to the intelligent animals on Earth.”