The beetle Darwin could not let escape

Charles Darwin once valued a rare beetle more than his dignity.

As a young man, Darwin collected beetles with enormous enthusiasm.

With a different beetle in each hand, he spotted a third rare specimen and put one beetle in his mouth to free a hand.

The insect released an unpleasant chemical, and in the confusion Darwin lost more than one prize.

The detail changes the usual picture of Charles Darwin. A famous life can look inevitable from a distance, but close up it is built from experiments, accidents and small decisions.

Progress often begins when clear evidence makes an invisible problem easier to see.