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This article has appeared in:

The McGill Reporter

Image courtesy of La Researche

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A not-so bird brained idea

by Ian Popple

It was once believed that the function of the brain was to cool the blood. That theory went extinct before the Dodo, but despite the now accepted knowledge that the brain is involved in processes of thought, we are still little further in unlocking many of its mysteries. Professor Louis Lefebvre and his team of researchers in the Department of Biology at McGill University have been studying the evolution of intelligence for the past 7 years. By focusing their research on innovative bird behaviours, they have managed to shed light on some of the mind-bending questions that have perplexed scientists for centuries.

Since the early 1800's scientists had suspected that brain size was linked to intelligence. German neuroanatomist Franz Joseph Gall suggested that organisms with a large brain relative to body size might be of greater intelligence than those with a smaller brain. The theory sounded reasonable enough, but until recently a suitable method of testing this idea had eluded scientists. The trouble is that intelligence is particularly difficult to define, let alone measure. "Previous attempts to establish animal intelligence used standardized IQ-style tests, which were unfair to certain species and out of touch with real life situations", explained Lefebvre. "We had to find a whole new way of measuring intelligence". By recording the ability of animals to find solutions to problems in a natural setting - to innovate and learn in the wild - Lefebvre developed a new, unbiased method of measuring their intelligence.

In 1994 Lefebvre started to collate reports of wild bird innovation to investigate the relationship between brain size and intelligence. "Birds are incredible innovators", explained Lefebvre. "People love to bird watch and record these behaviours." Nowhere is this more apparent than in Britain, where membership to the Royal Society for the Protection of Birds is nearly four times greater than membership to Tony Blair's ruling Labour Party. The scientific journal British Birds devotes numerous pages to observations of novel bird behaviour provided by amateur enthusiasts and scientists alike. Much like the game of cricket, the British love of birds spread through many of the Empires' former colonies. Consequently, examples of innovation in birds can be found in great abundance from around the world. Lefebvre has documented over 2000 new innovations from more than 500 different bird species. Interestingly, feeding behaviours are the most reported innovation. One of the most commonly cited examples of a feeding innovation is that of the European blue tit; In Britain, where milk is delivered to household doorsteps, blue tits are commonly found opening the tin foil bottle caps in order to feed on the cream. Other examples may be less familiar but equally, if not more remarkable. For example, in New Zealand, house sparrows gain access to cafeteria food supplies by triggering the motion sensor that opens the door. In Australia, skua feed alongside elephant seal pups on the milk from their lactating mother. Greenback herons can be found around the world using bread and insects as bait in order to catch fish. Using innovation reports like these, Lefebvre has been able to rate bird groups according to their intelligence and confirm a positive correlation between brain size and intelligence in birds. "The common crow has one of the highest brain to body size ratios" said Lefebvre. "In human IQ terms it would be around 135". In contrast the IQ of the average person is 100.

So what are the world's most intelligent birds? Woodpeckers rank high in the bird intelligence pecking order. As an example of their innovation, take the gila woodpecker found in the south west USA and Mexico that fashions a wooden scoop out of tree bark to carry honey home to its young. Also high in intelligence are birds of prey (e.g. hawks, eagles and falcons). Bald eagles in northern Arizona have discovered that dead minnows lay frozen under the surface of ice-covered lakes. On lakes where the ice is thin, eagles can be found chipping holes in the surface. This alone is not enough to earn them their meal however; the eagles then jump up and down on the surface of the ice, using their body weight to push the minnows up though the holes. The most intelligent bird group according to Lefebvre's research are crows. The Japanese carrion crow exhibits a remarkable behaviour that demonstrates why this bird is at the top of the "bird brain" charts. At a university campus in Japan, carrion crows have developed a unique feeding innovation that exploits human technology. Carrion crows perch at traffic intersections and patiently wait for the red light. When the vehicles come to a stop, the crows spring into action - they fly down to the cars and place walnuts under the tyres. These crows are smart enough to have figured out that the simplest way to open a nut is to get someone else to do it for you!