Single-rotor helicopters might not be thin on the ground, but their inspiration — a sycamore seed twizzling through the air — is not just one of nature’s more remarkable autumnal sights. It's also a ...

Sycamore seeds are also known as ‘helicopter seeds’, ‘whirlybirds’, ‘spinning jennies’, and ‘wingnuts’, and both sycamore seeds and ash keys are also called ‘samaras’ after the ...