There are at least 4 million people who have seen this video of a chicken keeping its gaze fixed while its body is forcefully moved around. It’s a really fascinating thing to watch and is worth understanding further.

It even caught the fancy of a certain German car manufacturer who decided to use chickens in one of its commercials to advertise an “intelligent stability” feature. I doubt chickens conform to the “intelligence” part though (sorry, all you global chickens).

But the explanation? Digging through a bit yields Vestibulo-ocular reflex (or its lack thereof in certain animals) as the culprit for this visually strange phenomenon. Humans exhibit the VOR ability and thus when we fix our gaze on any object, moving our head around does not cause us to lose track of the focused object - and this is done by compensating for the movement throught eye adjustment (for instance, if our head turns towards the right our eyeballs rotate towards the left).

But not all animals have this ability, especially a lot of birds. The gaze does stay fixed, but instead of the eyes compensating for maintaining focus, the neck muscles do the job (and thus it looks so strange). Imagine a human doing the same thing! Maybe we should really value our ability to rotate our eyes freely.

And as is the field of science, there’s already substantial research on why birds behave like this. Interesting. Perhaps now it’s time to observe pigeons bobbing their heads and find out why.