How does a single cell build a brain with billions of precisely organized neurons? Researchers suggest that brain cells use their lineage—their cellular family tree—as a kind of positional map. Cells that come from the same ancestor stay near one another, helping the brain organize itself without relying solely on chemical signals.

How does a single cell build a brain with billions of precisely organized neurons? Researchers suggest that brain cells use their lineage—their cellular family tree—as a kind of positional map. Cells that come from the same ancestor stay near one another, helping the brain organize itself without relying solely on chemical signals.