How much of 'us' is really 'us'?

Some time around 1683, amateur Dutch scientist Antonie van Leeuwenhoek scraped the plaque from between his teeth and peered at it through a home-made microscope.

Beyond chemistry: How mechanical forces shape brain wiring

During brain development, neurons extend long processes called axons. Axons link different areas of the brain and carry signals within it and to the rest of the body. Growing axons "wire up" the brain by following precise ...