The Struck Edge
The deliberate fracture of stone to produce a cutting edge — the oldest known technology.
At Lomekwi 3 in Kenya, stone cores and flakes dated to 3.3 million years ago record the earliest confirmed act of knapping — the controlled percussion that reads the conchoidal fracture of silicate rock and exploits it. The toolmaker, likely a late australopith, understood that a sharp angle could be forced into existence and that the product would outlast the maker's hand. These artifacts predate the genus Homo by several hundred thousand years, pushing intentional technology deep into a world of creatures we do not yet fully name.
The Oldowan tradition, beginning around 2.6 million years ago in Ethiopia, systematized what Lomekwi began. Its practitioners selected specific raw materials — fine-grained basalt, chert, quartzite — carried them kilometers from source outcrops, and shaped them by a two-step reduction sequence: a core trimmed to a working edge, and detached flakes used directly. This is combinatorial planning: material properties read in advance, transportation routed, striking angle calculated. Every subsequent technology inherits this cognitive template.
What it unlocked
Stone tools unlocked access to marrow, tubers, and meat at a scale that restructured hominin diet and, with it, the trajectory of brain evolution.
The evidence
Lomekwi 3 flakes (Kenya, 3.3 Ma, Harmand et al. 2015) and Ledi-Geraru cut-marked bones (Ethiopia, 2.6 Ma) establish the core-flake sequence before Homo habilis.