The Secret of Our Success

After transporting what looked like a dead, charred log to her distant garden, I saw a Matsigenka woman breathe life back into a hidden ember using a combination of dried moss, which she brought with her, and thermal reflection from other logs. I was also embarrassed when another young Matsigenka woman, with the requisite infant slung at her side,

Measured over body surfaces, no other animal can sweat faster than we do.

The results were striking. Regardless of age, many infants flatly refused to touch the plants at all. When they did touch them, they waited substantially longer before doing so than they did with the artifacts. By contrast, even with the novel objects, infants showed none of this reluctance. This suggests that well before one year of age, infants c

hunters do not produce enough calories to even feed themselves (let alone others) until around age 18 and won’t reach their peak productivity until their late thirties. Interestingly, while hunters reach their peak strength and speed in their twenties, individual hunting success does not peak until around age 40, because success depends more on kno

Making fire is so “unnatural” and technically difficult that some foraging populations have actually lost the ability to make fire. These include the Andaman Islanders (off the coast of Malaysia), Sirionó (Amazonia), Northern Aché, and perhaps Tasmanians. Now, to be clear, these populations couldn’t have survived without fire; they retained fire bu

This imaginary ancestral primate crossed a crucial evolutionary threshold as it entered a regime of cumulative cultural evolution. This threshold is the point at which culturally transmitted information begins to accumulate over generations, such that tools and know-how get increasingly better fit to the local environments—this is the “ratchet effe

For example, suppose long experience fishing will tend to cause anglers to prefer the blood knot to other potential knots (for connecting monofilament line) because the blood knot is objectively the best. However, individual experiences will vary, so suppose that long experience alone leads to only a 50% chance of an angler converging on the blood

cooking is probably the most important piece of cultural know-how that has shaped our digestive system. The primatologist Richard Wrangham has persuasively argued that cooking (and therefore fire) has played a crucial role in human evolution. Richard and his collaborators laid out how cooking, if done properly, does an immense amount of digestion f

interaction between cultural and genetic evolution generated a process that can be described as autocatalytic, meaning that it produces the fuel that propels it. Once cultural information began to accumulate and produce cultural adaptations, the main selection pressure on genes revolved around improving our psychological abilities to acquire, store