Modern research shows the public work together selflessly in an emergency, motivated by a strong impulse to help

It was early morning on 1 January last year when Colin McGarva dived into a flooding river in Worcester to rescue an unconscious woman. McGarva said he didn’t think twice about the risk to himself, or the devastating loss his newborn son would suffer had he too been swept away by the fast-flowing icy waters.

“I didn’t stop to think because the instinct – the instant reaction – is to help someone in need,” he said. “Someone’s life is an important thing. Helping is just something you have to do.”