sf-isms.a field guide to san francisco slang

noun · first recorded 2014 · status: og

Cambrian explosion

1.The keynote's favorite fossil: any moment when a lot of similar startups appear at once. Borrowed from 540 million years ago, deployed quarterly, and nobody ever mentions that the Cambrian's other export was mass extinction.

Third keynote this month to announce a Cambrian explosion of agents. The trilobites also felt optimistic.

01Origin

The actual Cambrian explosion is paleontology: the burst, half a billion years ago, when complex animal life diversified wildly in a geological instant. Tech borrowed it as the prestige way to say "suddenly there are a lot of these," and it has headlined every platform shift since the app store era. Falling costs plus a new primitive equals podium, slide, trilobite.

The AI boom put the metaphor on a treadmill: a Cambrian explosion of models, then of wrappers, then of agents, each announced by people who used the phrase for the previous one. Shopify's CEO promises a Cambrian explosion of creativity in shopping; the timeline documents an "Agentic Cambrian Explosion" in real time, struggling to keep track of the new species; and every VC deck has a slide where the speciation chart goes vertical.

The word does one honest job: it admits nobody knows which body plans survive. The original Cambrian produced wonders and also entire phyla that exist only as flattened fossils, which makes it a more accurate metaphor than its users intend: most of the explosion is future shale. See wrapper for last cycle's dominant species, we sell to agents for this one's, and Claude just killed X for the extinction events between.

02Notable sightings

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04See also