SCIENCE LAB SCENTS* : SERPENTS

Serpent Scents : Clear evidence that snakes can be deceptively clever.

Say the words '' animal self-recognition '' and many scientists will think of chimpanzees, crows and elephants. 

But researchers have found evidence that garter snakes can distinguish themselves from others, using not sight but scent.

Noam Miller, a comparative psychologist at Wilfrid Laurier University in Ontario, Canada, and an author of a new paper in the Journal Proceedings of the Royal Society B, said, '' There's a bias out there that they're these boring, not very cognitive animals, and that's completely wrong.''

One sign of cognition has been whether an animal can recognize itself in a reflective surface, a trait thought to be a proxy for more sophisticated intelligence.

The test involves marking an animal with paint somewhere visible only in the mirror and waiting to see if it investigates the change.

Similar tests have been conducted with a range of species : elephants [ passed ], pandas [ failed ] and roosters [ passed ]. But the mirror test is geared toward animals that are primarily visual. Many species  -such as snakes- rely mostly on their sense of smell.

Two species of snakes were tested : North American eastern garter snakes, predators of insects and fish and, African ball pythons, a largely solitary snake that ambushes rodents.

Snakes, like humans, have oils in their skins that leave a scent trail. The team rubbed nakeup removal pads along the snake's underside to collect scent samples, some of which they doctored with olive oil, and the modified or unmodified odors of other snakes of the same species.

The snakes interest was measured by gauging how long they flicked their tongues to taste the air -longer indicated sustained interest. The hail pythons showed no apparent distinction. But the garter snakes zeroed in on their own tempered smell and ignored variations of the other snakes' smells. [ Asher Elbein ]