“On “Model Organisms”” by J Bostock

This post was written while working for Arcadia Impact's Alignment Team (and grew out of an internal talk I gave) but is my own opinion and not theirs. I am grateful for feedback from Daniel Tan and the rest of the team.

This post was originally going to be more heavily about “model organisms” in AI safety research. But Francis Rhys Ward already wrote an excellent taxonomy which mostly covers that. So this is mostly about the history of the terms we're using, and about biology.[1]

TL;DR what are you studying? Are you studying a production language model in order to infer things about how language models behave in general? Are you studying a model with a specific intervention to prove that intervention's effects? Or are you studying a model with a specific property, in order to make inferences about that property in other language models?

Model Organisms in Biology

When a biologist uses the term model organism, they’re typically referring to a certain species, like Mus musculus, the lab mouse, or Arabidopsis thaliana, a type of pavement weed used in plant biology.

If you want to run an experiment today, you’ll use mice instead of gerbils, for a [...]

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Outline:

(01:00) Model Organisms in Biology

(02:49) Knockouts and Mutants in Biology

(04:06) Disease Models in Biology

(06:16) "Model Organisms" in AI Safety Research

(07:50) Wait, wait, wait... "Naturally Occurring"?

(09:09) Proposed New Terminology

The original text contained 1 footnote which was omitted from this narration.

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First published:
June 18th, 2026

Source:
https://www.lesswrong.com/posts/6Zc5tq6z5PjNhHH9T/on-model-organisms-1

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Narrated by TYPE III AUDIO.