My kids will sit by the chicken coop for long stretches, watching in amazement as our chickens spy insects in the soil and snatch them perfectly with their beaks. Mysterious are the powers of the hen.
Such as this one: their ability to detect my slightest movements in the morning from the far corners of their chicken coop, clear across the yard, and through the double-paned glare of our sliding door. I know they see me, because they start that eager marching and chattering they always do when they sense food is imminent. It’s as though they have some superhuman motion-detection hardware installed in their head.
Well, as it turns out, they do.
Researchers at Washington University School of Medicine in St. Louis studying the eyes of chickens have discovered “a masterpiece of biological design.” You can read about the research here.
Chickens’ superior color vision has something to do with never having spent any evolutionary time in the dark, whereas mammals were nocturnal for millions of years.
Night-vision relies on receptors called rods, which flourished in the mammalian eye during the time of the dinosaurs. Daytime vision relies on different receptors, known as cones, that are less advantageous when an organism is most active at night. Birds, now widely believed to be descendants of dinosaurs, never spent a similar period living mostly in darkness. As a result, birds have more types of cones than mammals.
It’s pretty interesting stuff. It might even explain the apparently hypnotic hold these birds have on my kids.