Butterfly wings are a bit of a mystery and “conventionally considered aerodynamically inefficient”. Researchers have analysed air flow movements behind butterfly and mechanical wings, and found that their wings clap together during the upstroke thrusting the animal forwards. This is crucial for fast take-off and evasive manoeuvres and may help explain the evolution of wings.
This article was originally published by Bbc.co.uk. Read the original article here.