In WWII, Rita Levi-Montalcini sheltered in her childhood home in Italy. She cobbled together a lab in her bedroom, and with bombs falling around her, she used fertilized chicken eggs to understand a fundamental question: how does our nervous system make accurate connections to its targets (muscles, etc) all over the body? She showed that during embryonic development, we make far more nerve cells than we need. Those nerve cells grow out everywhere, and the many nerve cells that fail to connect to targets just die. It's an extraordinarily wasteful mechanism, but it's also an extraordinarily robust way to make connections. Rita Levi-Montalcini
In WWII, Rita Levi-Montalcini sheltered in her childhood home in Italy. She cobbled together a lab in her bedroom, and with bombs falling around her, she used fertilized chicken eggs to understand a fundamental question: how does our nervous system make accurate connections to its targets (muscles, etc) all over the body? She showed that during embryonic development, we make far more nerve cells than we need. Those nerve cells grow out everywhere, and the many nerve cells that fail to connect to targets just die. It's an extraordinarily wasteful mechanism, but it's also an extraordinarily robust way to make connections.