Every once in a while newspapers publish these “popular science” articles that promulgate the latest fads in psychology, anthropology, or some such “fuzzy” social science. Here is one: Did evolution make our eyes stand out? Researchers test ‘cooperative eye’ hypothesis in humans and apes.

The cooperative eye hypothesis is that human eyes have a lot of white for ease of cooperation just by looking at eye movement.

In a new study that is one of the first direct tests of this theory, researchers from the Max Planck Institute for Evolutionary Anthropology in Germany looked at what effect head and eye movements had on redirecting the gaze of great apes versus human infants.

In the study, a human experimenter did one of the following:

- Closed his eyes, but tilted his head up toward the ceiling
- Kept head stationary while looking at the ceiling
- Looked at the ceiling with both head and eyes
- Kept head stationary while looking straight ahead

Results showed that the great apes … were more likely to follow the experimenter’s gaze when he moved only his head. In contrast, the 40 human infants looked up more often when the experimenter moved only his eyes.

Now, look… something must have gotten lost or this is a piece of pointless research that says nothing. I don’t see how this is a test of the hypothesis at all. Human eyeballs are more visible than ape eyeballs, so humans are more used to following eyeballs and apes are more used to following heads out of necessity. But this has nothing to do with evolution, has it? How does it show that cooperation necessitates more visible eyeballs? And what about cats and owls, who also have highly contrasting eyeballs?

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