A Monarch butterfly born in Canada will fly more than 3,000 miles to Mexico, across land it has never seen. Its journey is filled with peril, many never make it and those that do will never return.

A Monarch butterfly born in Canada will fly more than 3,000 miles to Mexico, across land it has never seen. Its journey is filled with peril, many never make it and those that do will never return.

Butterfly wings are a bit of a mystery and “conventionally considered aerodynamically inefficient". Researchers have analysed air flow movements behind butterfly and mechanical wings ...