A Romanian "Mioritic shepherd" dog watches a photographer in Bucharest June 5, 2004 during the first dog contest since the breed was internationally recognized one month ago. PHOTO - REUTERS

WASHINGTON - A clever border collie that can fetch at least 200 objects by name may be living proof that dogs truly understand human language, German scientists reported. Rico can figure out which object his master wants even if he has never heard the word before, the researchers say. The findings, reported in the journal Science, may not surprise many dog owners. But they are certain to re-ignite a debate over what language is and whether it is unique to humans. Rico's abilities seem to follow a process called fast mapping, seen when young children start to learn to speak and understand language.

Fast-mapping allows a child to form quick and rough hypotheses about the meaning of a new word the first time they hear or see it.

"(Rico) lives as a pet with his owners and was reported by them to know the labels of more than 200 items which he correctly retrieved upon request," Julia Fischer of the Max-Planck Institute for Evolutionary Anthropology in Leipzig and colleagues wrote.

Fischer and colleagues set up experiments to test the dog, and are satisfied that he understands the words. "For instance, he can be instructed to put them into a box or to bring them to a certain person," they wrote. "Rico's 'vocabulary size' is comparable to that of language-trained apes, dolphins, sea lions and parrots." When they put a new object into a room filled with old objects, Rico was able to fetch it 7 out of 10 times, evidently figuring out that the new word must refer to the new object. Four weeks later, he apparently remembered this new word about half the time. "This retrieval rate is comparable to the performance of 3-year-old toddlers," they wrote. They noted that border collies are bred to respond to human commands. But, they added, "our results strongly support the view that a seemingly complex human linguistic skill previously described only in human children may be mediated by simpler cognitive building blocks that are also present in another species." Obviously, they said, children have a deeper and broader understanding of words. But it could be that some of the mechanisms underlying language evolved "before early humans were ready to talk."

Psychologist Paul Bloom of Yale University in Connecticut, an expert in how people learn the meaning of words, said not even chimpanzees have demonstrated such "fast-mapping" abilities. But Bloom also noted that a child's understanding of language can include abstract concepts. "When children learn a word such as 'sock,' they do not interpret it as 'bring-the-sock' or 'go-to-the-sock,' and they do not merely associate it with socks," he said.

Reuters