I have long puzzled over how butterflies move and change direction so rapidly – they don’t seem to have the buzz power of bees or the skeletal and muscular structures of birds. Apparently, engineers are interested in the subject too, for possible application to extra-terrestrial flying robots. Researchers at the University of Oxford may now have found part of the answer (letter to Nature, 12 Dec 2002): butterflies can choose between six different wing actions during flight. But others reckon an insect brain may have only about 3000 neurons, giving them ‘less computational power than a toaster’, which hardly seems enough for the job.
Butterflies are wispy things
With skinny bodies, flimsy wings.
They really don’t look very strong,
And yet they seem to get along.
They’re pretty nifty little movers
Who execute some cool manoeuvres:
Their flight controls are so precise
They change direction in a trice.
You’d think a breeze, with little force,
Would blow a butterfly off course;
And air, to insects, is so sticky
That flying ought to be quite tricky –
No aerofoils to give them lift,
No buzzing wings to help them shift
(Compared to bees, their wings are slow).
How do they fly, I’d like to know!
Well, though their brains are rather small
(Three thousand neurons – seems that’s all),
It’s proved to be no handicap:
Their wings have learned six ways to flap.
They’ve found out how their wings can tease
Out streams of useful vortices:
They flap and twist, and ‘clap-and-fling’,
Then catch the lift their efforts bring.
Wing-flapping’s what our engineers
Have tried to duplicate for years;
But butterflies, as you’ll have guessed,
Have always known they do it best!