The Paradigm Revolution

Birds are cooler than most people think. It may be the years of living in close proximity or the random splattering of bird crap on our cars that leads to this avian antagonism. Misperceptions about their tiny brains limit most of the fascination of them to long-held clichés like the wonder of flight or the novelty of nesting, but birds deserve better. Even the lowly and obnoxious crow has the memory of an elephant and fashions tools as well as any chimpanzee.

Having evolved from theropod dinosaurs in the late Jurassic, birds are a relatively young class in the greater taxonomy of life. The ability to fly was so prolific an adaptation, that the ancestors of modern birds quickly filled many of the evolutionary niches that they occupy today. Flight allowed them to evade terrestrial predation and migrate continental spans. Their many habitats encouraged the natural selection of birds best suited for a vast panoply of tasks. This diversity manifests itself today in species as distinct as the golden eagle is from the penguin or the finch from the ostrich.

Flight necessitates a high degree of adaptability. Covering immense distances or traversing otherwise impassible terrain introduces the many hazards associated with new sources of food, different predators, and unusual habitats. Birds that were flexible and quick learners thrived in these environments and out bred their less innovative siblings. So it’s no surprise then that many modern birds are crafty and display great ingenuity. Several species within the Corvidae family (including crows, rooks, and jays) demonstrate an amazing degree of planning and adaptability. Researches recently documented crows dropping pebbles into a container partially filled with water to raise the water level sufficient enough for the bird to have a drink. This reinforces the ancient anecdote from Aesop’s fable of the crow and the pitcher. The video below shows a crow shaping a wire to snatch an otherwise inaccessible container of food.

Not only are crows innovative, but they have an amazing knack for remembering faces. John Marzluff of the University of Washington was trapping and tagging birds for research when he began to notice that crows were nearly impossible for the same person to trap twice. Leave the previous trapper in the car and send out a rookie, and the birds reacted as if there was no threat at all. Intrigued by this phenomenon, Marzluff designed a means to test this hypothesis. After gathering some volunteers and cranial accessories, he measured the intensity of the crows’ reaction over time between people wearing different masks and hats. The results are amazing: crows have an uncanny memory for faces. Once a mask was used by a trapper, 90% of crows in the area exhibited aggressive behaviors like scolding and dive-bombing whenever that mask was donned. When a person wearing a mask not used when trapping entered the same area, only 5% of the crows exhibited this boisterous reaction. The height, weight, and gender differences of trappers wearing the same mask had no bearing on the crow’s behavior. Four years after the research began, these crows still react to the first masks used. Not only that, but new crows in the area (evidenced by their lack of tagging), responded the same way to the masks without ever associating them with a trapper. They learned which masks to fear from their neighbors, and soon reacted just as aggressively in the absence of tagged crows. Marzluff observed how different his notion of solitude became when he appreciated that the birds were constantly taking account of his actions.

Darwin was not misguided by his fascination with finches. Birds encompass an amazing array of life on Earth, and their multitude of characteristics make them an interesting study. Next time you see a crow near your house, consider that it may remember your face with more precision than your spouse or closest friend.

~ by Wil Finley on February 25, 2010.

Posted in Science
Tags: birds, crows, evolution, flight, John Marzluff, memory, tool use