2975: Nodding for Yes: Near Universal Feb 12, 2025

In basically all of the world, nodding for yes and shaking for no developed is the standard, and seems to have developed independently across Eurasia, Africa, Australia, and the Americas. There are only a handful of cultures that also maintain such a system in the reverse, which will be discussed more in tomorrow’s post.

It is not known why this is, but it’s been theorized that its universality comes from associating head shaking with avoiding unwanted food, or other contact with the head. It is less clear why nodding for yes is as widespread, but this may be related to jumping excitedly.