A fish so small you can read through it just gave science the first full cell map of an adult vertebrate

Danionella cerebrum is a fish barely a centimetre long — so transparent that printed letters show through its body, and its brain is visible through the top of its head. That made it perfect for an audacious project at the Whitehead Institute: profiling more than 600,000 cells from across its whole body to build the first complete map of which genes are active in which cells of an adult vertebrate. Published in Science and released as a free public atlas, the map even let researchers trace how the fish regrows neurons after brain injury — a reference every biologist studying a single organ can now borrow from.

SDG 9 · Industry, innovation and infrastructure — Mechanism: tech innovation