THERE IS, ACCORDING TO author Douglas Adams, a knack to flying: throw yourself at the ground and miss. Humans are terrible at flying. We are too big, too heavy, too wingless. Insects, though, thrive in the air, and developing the ability to fly has played a large part in their success. With wings you can escape a predator; move to more advantageous habitats; radiate, diversify and take over the world. The first insect flew at least 325 million years ago, and it quickly caught on. Like the Duke of York's men, once they were up they were up- and for them there was no coming down.
Insect flight manifests itself in many different ways, whether it's the breathtaking control of a dragonfly, the exasperating agility of a house fly, the winsome scattering of a cabbage white, the dogged whirring of a stag beetle or the clumsy bumblings of a daddy long legs.
The principle is simple: four forces - lift, thrust, weight and drag - act on a flying body. Produce enough lift and thrust to counteract the weight and drag, and up you go. Yet the reality is more complex. The conundrum facing any flyer is to combine lightness with strength. Insects solve this by making their wings from the same stuff predominant in their exoskeletons: chitin.
The typical insect wing is a sandwich of this highly effective, lightweight material: two layers squeezed together and interlaced with a network of veins, which serve the dual purpose of strengthening the wing and circulating blood (haemolymph in insects).
SO THAT'S THE LIGHTNESS AND strength taken care of. But to get (and stay) in the air you need a form of propulsion and, as an insect wing contains no muscle, that must come from the body. Insects have evolved two solutions for this. The simpler version is the direct flight mechanism, which is utilised by two orders: Ephemeroptera (mayflies) and Odonata (dragonflies and damselflies), as well as some cockroaches.
Denne historien er fra July 2023-utgaven av BBC Wildlife.
Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.
Allerede abonnent ? Logg på
Denne historien er fra July 2023-utgaven av BBC Wildlife.
Start din 7-dagers gratis prøveperiode på Magzter GOLD for å få tilgang til tusenvis av utvalgte premiumhistorier og 9000+ magasiner og aviser.
Allerede abonnent? Logg på
Does cloning create identical copies?
EMBRYOS ARE MADE OF STEM CELLS that divide to give rise to different types of cells, everything from skin to brain cells. Scientists once thought that reproductive cloning creating a genetically identical copy of an individual organism - would be impossible without using stem cells and that the path leading to mature 'differentiated' cells was irreversible. But clawed frogs proved them wrong...
Tool-using animals
Our pick of 10 species that exhibit this special skill
Mission Blue
Sylvia Earle has dedicated her life to marine conservation; she tells BBC Wildlife why protecting the ocean is essential to all life on earth
RESHARK
The world's first shark rewilding initiative has seen zebra sharks released in the waters of Indonesia's Raja Ampat archipelago
ON DECK
Ferries aren't just for transport, they're also perfect vessels for conservation
IT'S A COLOURFUL LIFE
Delve into the unique and complex biology of the clownfish, arguably the world's most famous fish
BAHAMAS BENEATH
A dive into the waters of this famous island nation with the creatures that call it home
"To save the reef, we need everybody involved"
Indigenous peoples may hold the key to protecting the Great Barrier Reef
SPINNING AROUND
Going around in circles proves fruitful for this filter-feeder
BLINDED BY THE LIGHT
On balmy evenings, amorous beetles put on a spellbinding show in North American forests