NASHVILLE, Tenn. - There's no way to scientifically prove animal intelligence, but professor Steve Davis is sure animals on the farm have minds and can think.
Most of his fellow faculty and graduate students at Oregon State University agree, although nobody gives rocket scientist status to a chicken or turkey.
In a paper presented here today (July 31) at the annual meeting of the American Society of Animal Science, Davis reported that more than 80 percent of those he surveyed believed animals have minds and can think.
"As for myself," Davis said, "I subscribe to the Charles Darwin theory - that animal minds differ from human minds only in degree, not in kind.
"In that regard, I disagree with some of today's scientists who endorse Darwin's theory of evolution, but don't support his idea that animals are evolving both physically and mentally."
Davis said the concept of animal minds and intelligence is central to the Animal Protection Movement.
"At one end of the movement are animal (rights activists) who virtually say humans shouldn't use animals for any purpose," Davis said. "At the other end are those that say God has given men dominion over all the animals, and therefore we can use them anyway we want.
"People join one camp or another based on their perceptions. Animal agriculture needs to be paying attention to those perceptions. The more we know about perceptions and animal intelligence, the more humanely animals will be treated."
Davis said those with different philosophies will probably look at his survey data and interpret it differently, depending on their biases.
"For most, the data support a continuation of the status quo in animal agriculture - but only so long as the animals are treated in accord with their intelligence," he said. "However, many respondents, including animal scientists and veterinarians, believe some production confinement systems are not humane."
Nearly all those surveyed said animal species differed in intelligence. Respondents ranked eight species in this order: dog, cat, pig, horse, cow, sheep, chicken and turkey.
"There was a pretty clear division between the top four and the bottom four," Davis said. "In the top group, only the pig would be considered in the United States as an animal raised for food.
"Regardless of our background, we all seem to perceive the relative intelligence of these species the same way. Perhaps that's because of our lifetime experience and our education. For example, most of us have heard that the pig is the most intelligent farm animal, and many people have pot-bellied pigs as pets or have seen the movie 'Babe,' in which the pig portrays human-like intelligence."
Davis said scientists have been unsuccessful in measuring absolute animal intelligence.
"Behavioral scientists may say every animal is smartest for its own ecological niche," he explained. "The limitation in measuring cross-species intelligence is the inadequate tools for assessment we have available. Standard methods of assessment may show one species to be smarter on one test than another species, but a different method might show just the opposite."
The groups surveyed included faculty and graduate students in animal science and zoology; faculty in veterinary medicine, English and philosophy, and members of the Oregon branch of the American Association of Laboratory Animal Sciences, who are in charge of university research animals.
They were asked, "Does (species) difference in mental capability have any bearing on our responsibilities to them?"
"Some said no, because we have a duty to treat all animals with respect, regardless of their intelligence - that we should respect their needs and treat them humanely," Davis said.
"Some said yes, because the more intelligent species require different management to keep these animals from becoming bored.
"Others said yes, because we have to take especially good care of the stupid ones or they could panic in response to stress and hurt themselves."
Davis, 55, was raised on a family farm in Idaho. In addition to crops, the family raised dairy cows, horses, pigs and chickens.
"When I was young, I thought, 'Animals probably have minds, but mostly they react out of instinct.'
"I've changed since then. Now I believe animals do think. They do apply a certain amount of logic in problem solving. But they are different from humans in that they don't have the depth of intelligence."
Davis said his change in thinking has had an impact on his career.
"My research used to center on animal endocrinology - how farm animals can grow better. Now I'm switching to more contentious contemporary issues like animal rights and animal welfare. Animal scientists can no longer avoid the issues, the debate. We've got to be part of the solution."