Dr. Doolittle in the Doghouse
If we encountered another intelligent species on another planet, could we understand them? In turn, could extrasolar species decipher one of our eight-thousand terrestrial languages in use today?
|Digital cave painting has been part of signals sent into deep space as indicators of human perception and representation|
Credit: SETI Institute/ Arecibo
To better understand the deeper connection between language and intelligence–two key steps in improving the probabilities of contact with intelligent life elsewhere in the universe– the SETI Institute shephards this relatively new field in astrobiology. For instance, Dr. Laurance Doyle of the SETI Institute works with biologists Brenda McCowan and Sean Hauser, of the University of California, Davis, studying non-human communication systems. Doyle’s group, which also included Institute colleagues Dr. Christopher Chyba and Taylor Bucci, have already explored communication between sea mammals, like feeding humpback whales near Glacier Bay, Alaska.
|"[Contacting other civilizations] is very expensive; it’s better to spend our resources listening." -Frank Drake |
Image Credit: Arecibo Radio Telescope, NASA
If one considers the classic probabilities for such contact to succeed, the likelihood is governed by the Drake Equation, a formula for divining what might enable two different species to talk intelligently. One specific term in the Drake equation captures the probabilty that intelligence has evolved on another planet. But a pragmatic and implicit part of that probability hinges on whether humans and another species might be able to understand what the other one is trying to communicate. The problem poses a dilemma: can a species be considered intelligent yet unable to communicate its own wit to others?
Astronomer Guy Consolmagrio posed the scenario directly: "[It's possible] we find an intelligent civilization and there’s no way in creation we can communicate with them because they’re so alien to us. We can’t talk to dolphins now. In which case, we’ll never know."
Identifying examples of successful human to non-human communication offers few complete cases to study. Humans have considerable challenges just to understand each other, much less another species. The search for a good working example however may hold promise as a nascent discipline to bridge inter-species language barriers. One case to consider is a familiar one: does your dog understand what you say?
Dog owners convinced of their pets’ grasp of human language may be validated, at least in part, by new research on the word-learning abilities of a German family’s Border collie. Scientists who studied a dog with an approximately 200-word "vocabulary" suggest that some aspects of speech comprehension evolved earlier than, and independent from, human speech.
|Rico, a dog with an approximately 200-word "vocabulary," can learn the names of unfamiliar toys after just one exposure to the new word-toy combination.|
Credit: Susanne Baus
This research appears in the 11 June 2004 issue of the journal Science, published by AAAS, the nonprofit science society.
"You don’t have to be able to talk to understand a lot," said senior Science author Julia Fischer from Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
Rico, the nearly nine-year-old Border collie, can learn the names of unfamiliar toys after just one exposure to the new word-toy combination. The scientists equate the dog’s apparent learning to a process seen in human language acquisition called "fast mapping." The fast mapping abilities of children allow them to form quick and rough hypotheses about the meaning of a new word after a single exposure.
"Such fast, one-trial learning in dogs is remarkable. This ability suggests that the brain structures that support this kind of learning are not unique to humans, and may have formed the evolutionary basis of some of the advanced language abilities of humans," said Katrina Kelner, Science’s deputy editor for life sciences.
The German team first verified Rico’s 200-word "vocabulary." In a series of controlled experiments, Rico correctly retrieved, by name, a total of 37 out of 40 items randomly chosen from his toy collection. The authors write that Rico’s "vocabulary size" is comparable to that of language-trained apes, dolphins, sea lions and parrots.
|Frank Drake (above) believes that there could be a million intelligent civilizations in the Milky Way galaxy, and probably billions of such civilizations throughout the universe.|
Image Credit: SETI
Next, the researchers tested Rico’s ability to learn new words through fast mapping. Fischer’s team placed a new toy among seven familiar toys. In a separate room, the owner asked Rico to fetch the new item, using a name the Border collie had never heard before.
Rico correctly retrieved a new item in seven of ten sessions. He apparently appreciates, as young children do, that new words tend to refer to objects that do not already have names. After a month without access to these target toys, Rico retrieved them, upon request, from groups of four familiar and four completely novel toys in three out of six sessions. His retrieval rate is comparable to the performance of three-year-old toddlers, according to the authors.
"For psychologists, dogs may be the new chimpanzees," writes Paul Bloom from Yale University in New Haven, CT, in an accompanying "Perspective" article in Science.
Scientists around the world are currently studying how chimpanzees learn language and communicate.
The authors do not claim that Rico and children have an equally rich understanding of words. They do show, however, that Rico can make the link between objects and sounds.
"This is a crucial step that allows an animal to figure things out in the environment," Fischer explained.
Fischer’s team is now investigating Rico’s ability to understand entire phrases, such as requests for Rico to put toys in boxes, or to bring them to certain people.
Fischer noted that people should not take this study as a reason to go out and get a Border collie as a novelty.
"Border collies are working dogs," Fischer said. "If they were humans, we’d call them workaholics. They are high-maintenance, professional dogs that need at least four or five hours of attention a day."
Related Web Pages
Doyle’s Whale Study
How Advanced Could They Be?
Anybody Out There? Part I
Anybody Out There? Part II
Search for Life in the Universe: Neil deGrasse Tyson Interview
Aliens Depend on Time to Grow Brains
James Cameron IV: The ET Challenge
The Great Debate: Is Complex Life Common in the Universe?
Cause for Optimism: Part III : The Drake Equation Revisited