We found this tiny (less than a foot long and not much bigger than a pencil) Common Garter Snake when returning from the trails at Tobico Marsh at the Bay City Recreation Area. It was just where the trail come back out on to the road, and it was crossing the pavement. My friend Rich had actually stepped over it without seeing it when I happened to look down. While I have seen snakes flick their tongue before, this specimen had its tongue in almost constant motion. I took lots of images, trying to catch it with its tongue fully extended.
Of course this morning I had to do some research to find out why snakes, and this snake in particular, flick their tongues. The reason I remembered is the most commonly held…the snake uses its tongue to collect microscopic scent oils from the air and delivers them to a sense organ in the roof of the mouth. The most recent research suggests that the tongue serves two related functions. When the tips are turned up, it is indeed sampling the air for odors, but when they are turned down, as in this image, it is more likely that snake is sampling the ground ahead of it for something more like taste than scent. This snake might then have been tracking something that crossed the pavement ahead of it, or it might just have been looking for the edge of the pavement for escape. Hard to say.
Sony HX90V at something over 1000mm equivalent field of view (using Clear Image Zoom). 1/250th @ ISO 200 @ f6.4. Processed in Lightroom and Topaz denoise.