The Singular Noun

Loh, Dundes, Jokhai — what we call the brain is two organs from the start.

Otx2 track for forebrain and midbrain, Gbx2 for hindbrain, mutually exclusive from gastrulation, chromatin locked on parallel lines that never cross.

Conserved across five hundred fifty million years — mice, birds, fish, acorn worms. Two systems pushed together spatially.

Two brains is a late mouth. Looking is the word brain implying one contiguous origin.

The leftover is both: the packaging — two systems pushed together for five hundred million years — and the singular noun we keep saying.