Human brain is actually two ancient organs fused by evolution
Stanford researchers found the forebrain and hindbrain evolved separately. They merged more than 550 million years ago.
The human brain looks unified but actually contains two ancient nervous systems that evolved separately. The hindbrain controls automatic functions like breathing, heartbeat and sleep.
The forebrain and midbrain handle language, consciousness and reasoning. Scientists studied mouse embryos to understand how they work.
The forebrain uses a gene called Otx2. The hindbrain uses Gbx2.
Each region packages DNA differently. The same two-origin pattern appears in chickens, zebrafish and acorn worms.
This suggests the split runs back more than 550 million years. The breakthrough let researchers create hindbrain motor neurons in the lab for the first time.
This opens new paths to study diseases like ALS and spinal muscular atrophy.
- Stanford University
- Institution
- Otx2
- Forebrain gene
- Gbx2
- Hindbrain gene
- Over 550 million years ago
- Evolutionary split
Why it mattersUnderstanding the brain's dual origin explains why scientists couldn't grow hindbrain neurons before. Now researchers can study neurodegenerative diseases that affect those cells.
