Human Brain Is Actually Two Separate Organs, Scientists Find

The human brain is not a single organ, but two separate systems that evolved independently before fusing together, according to groundbreaking new research.

Scientists at Stanford University made the discovery while trying to solve a longstanding laboratory puzzle: why brain stem cells were nearly impossible to grow in a dish, while cells from the front of the brain grew with ease.

By examining how the brain forms in its earliest stages, the team discovered that the front and back sections of the organ arise from completely different cellular starting blocks.

It had been believed that the entire brain developed from a single master parent cell.