Wing-flapping robot helps explain the evolution of insect flight

Some insects can flap their wings so rapidly that it's impossible for instructions from their brains to entirely control the behaviour. Building tiny flapping robots has helped researchers shed light on how they evolved to do this. If you flap your arms, each movement happens after your brain directs your arm muscles to contract and then relax. Something similar happens for many insects as they beat their wings. But for some, including mosquitoes, those brain signals and flapping are out of sync. After the initial signal to contract, the insects' muscles undergo additional contract-relax cycles before they even receive another impulse from the brain.