THURSDAY, May 7, 2009 (HealthDay News) -- Dogs share the same basic functional abilities as 2-year-old kids, at least when it comes to figuring out where older humans have hidden a treat.
So says a team of Hungarian researchers, who also found that 3-year-olds surpass their canine companions when confronted with the task.
At age 3, kids can locate a hidden toy by "reading" a pointed index finger, but younger children and dogs take their cues from the posture or direction of the hand, arm and torso -- even if an index finger is pointing in the opposite direction, the researchers found.
"Dogs are following the general direction that a body is extended," explained Bonnie Beaver, a professor at the College of Veterinary Medicine & Biomedical Sciences at Texas A&M University. "This helps tighten up specifically what are the things that trigger the dog to look. Wolves don't look [at what people are looking at], and that is a difference between the two."
Beaver was not involved in the new study, which was published online in the journal Animal Cognition.
And why this ability in dogs but not their ancestors, the wolf?
"Domesticated animals had to leave their natural environment and were moved to a new 'domestic' in which the human presence is the most important factor," said Gabriella Lakatos, lead author of the study and a research assistant in the department of ethology at Eotvos Lorand University in Budapest. "In the course of domestication, it became advantageous for the dog if they were controllable and so could comprehend the communicational signals of humans because this ability helps them to adapt to the human social environment."
Pets are often viewed as important family members by people and, in fact, enjoy a "parental" relationship with adults in the household similar to children, added the study's senior author, Adam Miklosi, head of the university's ethology department.
Dogs' understanding of human pointing gestures, which emerges around 2 to 4 months of age, has been widely studied. But children's, less so.
Using a variety of arm, leg, finger and elbow gestures, the researchers indicated the location of a hidden reward. The trials involved 15 dogs (roughly 5 years old), 13 2-year-old children and 11 3-year-olds in Budapest.
The researchers found that dogs paid attention to a protruding body part, as did the 2-year-olds. But 3-year-olds understood all the gestures presented, including a pointing index finger, and successfully retrieved the reward toy out of a brown plastic flower pot.
This seems to indicate that children experience a "growth spurt" in this area of development between the ages of 2 and 3, Lakatos said.
As for dogs, "in the course of the domestication, the human social environment became to be the natural environment of dogs, in which there are complex communicational interactions between humans and dogs," she said. "It is hypothesized that, because of their evolutionary and developmental history, dogs are sensitive to the human signals. And on the basis of the present results, it seems that their level of comprehension is proportional to the challenges set by their natural human social environment."
Does this mean that the intelligence of a dog can be compared with that of a 2-year-old? The authors said no.
"On the basis of the present results, we can only say that regarding the comprehension of human visual signals, at the functional level, dogs' performance is comparable to that of 2-year-old children," Miklosi said. "We would not say that the intelligence of a dog equals that of a 2-year old child."
On the other hand, dogs should continue to understand and (hopefully) follow these gestures all of their lives. But while human teenagers might still understand, they're less likely to obey.
The Humane Society of the United States has more on canine behavior.