MONDAY, Jan. 31, 2005 (HealthDayNews) -- It took 29 internationally renowned scientists to get the ball rolling, but the term "birdbrain" could be on its way out, at least in its pejorative sense.
"Birdbrain comes with two ideas: a small brain and also stupidity," said Erich Jarvis, an assistant professor of neuroscience at Duke University Medical Center, and one of the ringleaders of the group. "It just has to change."
Perhaps more relevant to the scientific community, Jarvis and the 28 other scientists have renamed the terminology for avian brain structures to reflect recent scientific discoveries. Those discoveries show that birds are actually closer to mammals when it comes to brainpower. Their arguments are detailed in a paper appearing in the February issue of Nature Reviews Neuroscience.
"The classic view is totally wrong," said Jarvis, who is also lead author of the paper. "I realized I couldn't publish papers with names that have wrong meanings attached to them. It is against my scientific conscience, and it is poor for scientific advance."
At the heart of the debate are competing views of evolution. The current nomenclature for avian brains was developed about 100 years ago by Ludwig Edinger, considered the father of comparative neuroanatomy. His view of evolution was linear and hierarchical, positing that humans were at the top of the evolutionary chain, the pinnacle of creation. Other creatures, including birds, were of "lower" intelligence and hadn't changed in millions of years. Their only purpose was to have given rise, evolutionarily speaking, to humans. Needless to say, the whole schemata was highly bird-ist.
The new view holds that most vertebrates inherited the same three major brain subdivisions from a common ancestor. These three areas control complex behavior.
"We're saying different vertebrate groups, such as birds, reptiles, amphibians and humans, inherited them and then independently amplified them into various structural differences," Jarvis said.
In the classic view, most of the avian brain was made up of basal ganglia, associated with primitive behavior, while the human brain exhibited more advanced behavior with having a large cortex. Hence, such terms as paleostriatum and neocortex. "Paleo" means "old" while "neo" means "new." Only humans, of course, had a neocortex, the supreme achievement.
"That's where you get lower and higher," Jarvis said. "I don't use higher and lower any more."
The modern view holds that the basal ganglia represents only a small portion of the total avian brain, as it does in humans, and that the avian brain, in total, has areas homologous to those in humans and known to be involved in complex perceptual and cognitive processes. The basal ganglia neurons are also organized in a similar way to humans, Jarvis said. The cortical-like regions in birds, however, are organized differently than in humans.
"Now, it's no wonder birds can do all these complex behaviors," Jarvis said. The complex behaviors include pigeons memorizing 725 different visual patterns and distinguishing between cubist and impressionistic paintings; scrub jays changing their food-storing behavior to thwart thieves; New Caledonian crows fashioning tools out of leaves and human-made materials; and, what Jarvis considers the height of bird achievement, the vocal learning exhibited by parrots, hummingbirds and songbirds. "It's the substrate for human language," Jarvis said. "Without it, you just don't have language." Some parrots can actually communicate with humans using words.
It took the 29 scientists seven years to get to this point, with 2,000 scientists in 16 countries involved in the dialogue. And many of the old guard apparently remain skeptical of the change.
Jarvis is undeterred.
"Some of us think it will have a big impact," he said. "The bird brain nomenclature of the classic view is a set of cards with terms at the lower end, and we just removed them. Now we will have to see what happens for changing the views on other species, including humans, which, by the way, were at the top of the card house."
But it might also be hard to gain acceptance from the general public.
Just ask one of the foremost publishers of language reference books.
Arthur Bicknell, the senior publicist for Merriam-Webster in Springfield, Mass., said words are constantly added or subtracted from the English language. "In many cases, an older meaning for a word can become so antiquated and so unused that it can fade away," he said. This happened with "snollygoster" (an irascible politician) in 2003.
This isn't likely to happen with birdbrain, however, which was first documented in 1933 as meaning "scatterbrained." In addition to scatterbrained, today's definition includes stupid.
Merriam-Webster's lexographers "have not been collecting evidence of any other meanings for the word, nor do they have any particular evidence that the word is fading out," Bicknell said.
And if it were to fade away from everyday usage, Bicknell added, the dictionary editors said it would be independent of any research having to do with birds.
They also said, according to Bicknell, "Even if we discovered remarkable things about birds, it's become assimilated into the language, so we'd probably still use it to mean stupid. Same thing if we found out wonderful things about jackasses."
To learn more about the nomenclature initiative, visit AvianBrain.org.