Clever Crows, Complex Cognition?
by Gisela Telis

Called “feathered apes” for their simianlike smarts, crows use tools, understand physics, and recognize themselves and humans. But new research suggests that the brainy birds may be even smarter than was previously thought. Given a complex problem and an assortment of tools, New Caledonian crows came up with a creative solution that hints at higher-order thinking. A native of New Caledonia and the Loyalty Islands in the Pacific Ocean, the New Caledonian crow makes tools from sticks or leaves and uses these to draw tasty grubs from hollows in trees. That in itself wouldn’t be so impressive—even some insects use tools this way—but the crows also combine tools when they needed to. In a 2007 experiment conducted by graduate student Alex Taylor and colleagues at the University of Auckland in New Zealand, the crows used a shorter stick to grab another that was long enough to get food outside their reach. This kind of action seems to indicate insight or reasoning. But not everyone was convinced, says Taylor. “Some scientists suggested the tools became valuable in themselves because they were associated with food,” he says. That would mean the birds sought each stick because they wanted it, not because they understood the stick’s potential function. The distinction, although subtle, marks the difference between high- and low-level learning, and it speaks to a central question of cognition research: How do you determine whether an animal is thinking through its actions, or simply learning through association a series of behaviors and combining them? © 2010 American Association for the Advancement of Science