Leptopilina boulardi by Alexander Wild

In a French meadow, a creature that specialises in corrupting the bodies of other animals is getting a taste of its own medicine.

Leptopilina boulardi is a wasp that lays its eggs in fly maggots. When the wasp grub hatches, it devours its host form the inside out, eventually bursting out of its dead husk. A maggot can only support a single grub, and if two eggs end up in the same host, the grubs will compete with one another until only one survives. As such, the wasps ensure that they implant each target with just one egg. And if they find a maggot that has already been parasitized by another L.boulardi, they usually stay away.

Usually, but not always.

L.boulardi is sometimes infected by a virus called LbFV, which stands for L.boulardi filamentous virus. And just as the wasp takes over the body of its maggot target, so the virus commandeers the body of the wasp. It changes her behaviour so that she no longer cares if a maggot is already occupied. She will implant her eggs, even if her target has an existing tenant. After infected wasps are finished, a poor maggot might have up to eleven eggs inside it.

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A black bean aphid is about to have a rough day. It has been targeted by a parasitic wasp, which lays several eggs inside its body. When the eggs hatch, the wasp grubs will try to eat the aphid from the inside out. If they succeed, the aphid will die, and the young wasps will burst from its corpse to find aphids of their own.

But the aphid isn’t necessarily doomed. There’s a chance that it will resist the attempt to usurp its body. If it does, the wasps will have done it a favour. When the mother wasp implanted its eggs, it also infected the aphid with bacteria that protect against parasitic wasps. It inadvertently vaccinated the aphid against its own kind.

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Some people drink alcohol to drown their sorrows. So does the fruit fly Drosophila melanogaster, but its sorrows aren’t teary rejections or lost jobs. It drinks to kill wasps that have hatched inside its body, and would otherwise eat it alive. It uses alcohol as a cure for body-snatchers.

D.melanogaster lives in a boozy world. It eats yeasts that grow on rotting fruit, which can contain up to 6 per cent alcohol. Being constantly drunk isn’t a good idea for a wild animal, and the flies have evolved a certain degree of resistance to alcohol. But Neil Milan from Emory University has found that alcohol isn’t just something that the insect tolerates. It’s also fly medicine.

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At first glance, we might think that all wasps look the same. But if you look closer at the face of a paper wasp Polistes fuscatus, you’ll see a variety of distinctive markings. Each face has its own characteristic splashes of red, black, ochre and yellow, and it’s reasonably easy to tell individuals apart. And that’s exactly what the wasps can do.

Michael Sheehan and Elizabeth Tibbetts have shown that these sociable insects have evolved the special ability to recognise each others’ faces. They can learn the difference between different faces more quickly than between other images, or between faces whose features have been rearranged. It’s an adaptation to a social life, and one that a close but solitary relative – Polistes metricus – does not share.

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Thrips are tiny insects, typically just a millimetre in length. Some are barely half that size. If that’s how big the adults are, imagine how small a thrips’ egg must be. Now, consider that there are insects that lay their eggs inside the egg of a thrips.

That’s one of them in the image above – the wasp, Megaphragma mymaripenne. It’s pictured next to a Paramecium and an amoeba at the same scale. Even though both these creatures are made up of a single cell, the wasp – complete with eyes, brain, wings, muscles, guts and genitals – is actually smaller. At just 200 micrometres (a fifth of a millimetre), this wasp is the third smallest insect alive* and a miracle of miniaturisation.

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You know how it is: one minute you’re having sex and the next, your partner has been stung and paralysed, and you’re being dragged off to a burrow by your genitals only to be buried and eaten alive.

Such is the life of the Australian plague locust, a common pest that is targeted by the black digger wasp. The wasp is a parasite that creates living larders for her grubs. She stocks them with the bodies of paralysed insects. Last December, the locusts formed dense plagues in southeastern Australia just as the wasps were starting to collect fresh meat for their young. And Darrell Kemp from Macquarie University was watching as the two species collided.

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Some parents give their children a head start in life by lavishing them with money or opportunities. The mother seed beetle (Mimosestes amicus) does so by providing her children with shields to defend them from body-snatchers.

A female seed beetle abandons her eggs after laying them. Until they hatch, they are vulnerable to body-snatching parasites, like the wasp Uscana semifumipennis. It specialises on seed beetle eggs and lays its own eggs inside. Once the wasp grub hatches, it devours its host. The wasp problem is so severe that around 70 percent of the beetles’ eggs can be infested.

But the mother seed beetles have a defence, and it is a unique one. Joseph Deas and Molly Hunter from the University of Arizona have found that they can protect an egg from this grisly fate by laying another one on top. Sometimes, the mothers lay entire stacks of two or three eggs. The tops ones are always flat and unviable. They never hatch into grubs and they completely cover the ones underneath.

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Hiring zombie bodyguards to look after your children can have its drawbacks. They might end up with fewer children of their own.

The wasp Dinocampus coccinellae is a body-snatcher, or perhaps a “bodyguard-snatcher”. She’s on the hunt for a spotted ladybird. When she finds one, she stings it and lays an egg inside its body. Her grub hatches and starts eating the ladybird alive. Around three weeks later, it bursts out of its host.

But the ladybird doesn’t die. The grub hasn’t consumed all of its internal organs, and it leaves the ladybird partially paralysed but very much alive. Once out, it spins a silken cocoon between the ladybird’s legs and over the next week, it slowly transforms into an adult. Meanwhile, the ladybird stands guard over its own parasite. Its warning colours of red and black should deter would-be predators, and it twitches erratically if threats draw near. Its tour of duty only ends when the adult wasp eventually emerges from the cocoon and flies away.

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It’s not a very fair fight. In one corner is a tiny ant. In the other is a large wasp, two hundred times heavier and capable of flying. If the two of them compete for the same piece of food, there ought to be no contest. But sometimes the wasp doesn’t even give the ant the honour of stepping into the ring. It picks up the smaller insect in its jaws, flies it to a distant site and drops it from a height, dazed but unharmed.

Julien Grangier and Philip Lester observed these ignominious defeats by pitting native New Zealand ants (Prolasius advenus) against the common wasp (Vespula vulgaris). The insects competed over open cans of tuna while the scientists filmed them.

Their videos revealed that ants would sometimes aggressively defend their food by rushing, biting and spraying them with acid. But typically, they were docile and tolerated the competing wasp. Generally, the wasp was similarly passive but on occasion, it picked up the offending ant and dropped it several centimetres away. In human terms, this would be like being catapulted half the length of a football field.

The wasps never tried to eat the ants, and they never left with one in their jaws. They just wanted them out of the picture. Indeed, the more ants on the food, the further away the wasps dropped them. This may seem like an odd strategy but at least half of the dropped ants never returned to the food. Perhaps they were physically disoriented from their impromptu flight, or perhaps they had lost the chemical trail. Either way, the wasps could feed with fewer chances of taking a faceful of acid.

Reference: Grangier and Lester. 2011. A novel interference behaviour: invasive wasps remove ants from resources and drop them from a height. Biology Letters http://dx.doi.org/10.1098/rsbl.2011.0165

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The wing of a fruit fly, viewed against a white background, looks very ordinary. It is transparent, with no obvious colours except for some small brownish spots. But looks can be deceptive. If you put the wing in front of a black background, it suddenly explodes in a kaleidoscope of colour. Oranges, blues, greens, violets – virtually the entire rainbow dances across the wing, except for red.

A French scientist called Claude Charles Goureau first noticed these vivid hues back in 1843. Since then, they have languished in obscurity, “apparently unnoticed by contemporary biologists”. Whenever new species of wasps or flies are described, their discoverers almost never mention the coloured patterns of the wings. The visible pigments have even been described as “evolution in black and white”. It’s like walking through an art gallery with a blindfold.

Now, Ekaterina Shevtsova from Lund University has taken off the blind. By photographing several species against dark backgrounds, she has revealed a world of hidden colour, rivalling that of more obviously beautiful insects. “The claim that fly and wasp wing patterns are no match for the incredible diversity of colourful butterfly wing patterns is obsolete,” she says.

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