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These colourful, hairy insects are beautiful to look at, but they have so many defences that virtually nothing eats them

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antIn a dry, open field in New Mexico, US, a hungry lizard spots a brightly-coloured, hairy insect scurrying across the sandy soil. Thinking it has found a meal, the lizard sprints to catch the insect. But once it has the insect in its mouth, it finds it is too hard to chew.

The lizard then moves the insect around to find a softer chewing angle but gets nowhere. Meanwhile the insect starts to squeak and finally stings the luckless lizard in its mouth. Alarmed, the lizard spits it out.

The insect, still squeaking, gets away unscathed. The lizard is left with nothing but a sore mouth and a foul taste.

This sturdy insect is a female velvet ant. These females have an arsenal of defences unmatched by their male partners, or any other insect. The question is, what terrifying predator forced the females to evolve so many defences? And if they are in such dire threat from predators, why are they brightly coloured?

A thistledown velvet ant (Dasymutilla gloriosa) (Credit: Visuals Unlimited/NPL)

A thistledown velvet ant (Dasymutilla gloriosa) (Credit: Visuals Unlimited/NPL)

Let’s get the confusing bit out of the way first. Velvet ants are not really ants: they are wasps. They got their name because the females look like large ants, albeit ants clothed in dense velvety hairs of various hues: they can be yellow, orange, red, white or black.

Female velvet ants have taken the idea of warning colouration to a whole new level

In most species, males are rather plain-looking. They are so unlike the bright and furry females, it can be hard to tell which male pairs with which female.

When faced with a predator, the males have an obvious advantage. They have wings, so they can simply fly away.

However, the females are both grounded and conspicuous. Their bright colours may seem like a dead giveaway, but they are actually a signal warning predators to stay away – just like the bright colours of a wasp warn predators that it can sting.

What’s more, female velvet ants have taken the idea of warning colouration to a whole new level.

Velvet ants mimic their neighbours (Credit: Joseph Wilson, Utah State University)

Velvet ants mimic their neighbours (Credit: Joseph Wilson, Utah State University)

Different species of velvet ants have evolved to mimic each other. By resembling other velvet ant species from their neighbourhood, these solitary creatures have found strength in numbers.

When a velvet ant becomes aware of a threat, it starts to squeak

Naïve predators that try to tackle a velvet ant soon get the message, and steer clear of them in future. By all flashing the same signal, the velvet ants ensure that they all share in this protection.

Among the velvet ants of North America, the colour mimicry is extremely widespread. In a study published in August 2015,researchers grouped over 300 species into just 8 mimicry clusters, based on similarities in colour, hair density and location. They range from silvery and downy velvet ants found in the hot deserts to the brownish-red and bald species found east of the Rocky Mountains.

But this colour signalling is just the start of the velvet ants’ arsenal. They also use a combination of audio and chemical signalling to deter predators.

It's cute, but this velvet ant is packing (Credit: Joseph Wilson, Utah State University)

It’s cute, but this velvet ant is packing (Credit: Joseph Wilson, Utah State University)

When a velvet ant becomes aware of a threat, it starts to squeak or “stridulate”.

Velvet ants can deter predators by releasing odours

It does this by moving different sections of its abdomen in and out. This motion rubs a tooth-like projection on the second section,the “scraper”, against a ridged structure on the third section, the “file”.

The resulting squeaky noise can warn off predators while they are still at a distance. But a velvet ant can also stridulate if it gets caught unawares and picked up in a predator’s mouth.

To the predator, that might feel “like a mini jackhammer going zzzzzzzzzzz” in its mouth, says entomologist Justin Schmidt of the Southwest Biological Institute in Tucson, Arizona, US. If this sensation was unpleasant enough, the predator would open its mouth and the velvet ant would escape.

On top of their squeaking, velvet ants can deter predators by releasing odours.

An unidentified velvet ant from the Namib desert (Credit: Solvin Zankl/NPL)

An unidentified velvet ant from the Namib desert (Credit: Solvin Zankl/NPL)

They have well-developed glands that secrete smelly “allomones”: chemicals that manipulate the behaviour of another species.

They are also agile and remarkably strong

Specifically, they make ketones, which ants are known to use as alarm pheromones. That makes sense: velvet ants often come across ants, so they may have evolved specific allomones to repel the ants, which Schmidt and his colleagues once described as “major potential predators” of velvet ants.

In experiments, tiny flags coated with one of these ketones were enough to trigger alarm behaviour among harvester and carpenter ant workers. The same flags also prompted fire ants to scatter until the ketones had evaporated. Similarly, fire ant workers fed less when their honey was laced with a cocktail of ketones.

So velvet ants look scary, sound scary and smell scary. They are also agile and remarkably strong.

Dasymutilla occidentalis, from South Carolina (Credit: Premaphotos/NPL)

Dasymutilla occidentalis, from South Carolina (Credit: Premaphotos/NPL)

In a study published in 1977, Schmidt and his PhD advisorMurray Blum presented velvet ants to a selection of predators, including ants, spiders, a praying mantis, lizards, birds and gerbils.

A velvet ant has a hard, slippery and rounded outer shell

When attacked by a few red fire ants, the velvet ants freed themselves by quickly scraping the ants off using their strong and muscular legs. However, when attacked by many ants at once, the velvet ant both removed the fire ants faster and ran faster to escape.

Schmidt and Blum repeatedly chased velvet ants with their fingers and estimated that they could scamper at about 0.5km/h (0.3mph). They can achieve these speeds because certain muscles, which in winged males control flight, are used to make the females’ legs stronger, says Schmidt.

A female velvet ant’s legs are so powerful, adds Schmidt, she can use them to wrestle her way out of a predator’s mouth. You might think that a bigger animal like a lizard could easily crush her in its jaws, but the velvet ant is too tough for that.

Hoplomutilla opima, from Trinidad (Credit: Premaphotos/NPL)

Hoplomutilla opima, from Trinidad (Credit: Premaphotos/NPL)

A velvet ant has a hard, slippery and rounded outer shell, and this saves it from being crunched. Schmidt and Blum calculated that the force required for successfully crushing a velvet ant is about 11 times that for a worker honeybee, and almost twice that for a stag beetle.

What it lacks in toxicity it makes up for in sheer pain

In line with that, when insect collectors try to pin down a dead velvet ant, they often miss because the pin glances off and pierces their finger.

Schmidt’s experiments show that a velvet ant’s tough shell helps to protect it from spiders, which try to inject it with venom.

If none of that is enough to deter a predator, a velvet ant packs a legendarily painful sting.

Dasymutilla magnifica, a velvet ant from Texas (Credit: David Welling/NPL)

Dasymutilla magnifica, a velvet ant from Texas (Credit: David Welling/NPL)

Only females have stingers. That’s because the stinger, which is highly flexible and half as long as the insect itself, is a modified egg-laying organ called an ovipositor.

Dasymutilla velvet ants are sometimes known as “cow killers”, which is ridiculous as their sting is essentially harmless

The venom from a velvet ant’s sting is only mildly toxic, being one of the least chemically active insect venoms compared to other stinging wasps, ants and bees. But what it lacks in toxicity it makes up for in sheer pain – something Schmidt can attest to.

In 2015, Schmidt was awarded an Ig Nobel Prize “for painstakingly creating the Schmidt Sting Pain Index, which rates the relative pain people feel when stung by various insects“. In a study published in 1984, he rated insect stings from 1 to 4, where 4 is the most painful, based on how it felt when insects stung him. So he knows exactly how painful a velvet ant sting is.

One genus of velvet ants is particularly excruciating.Dasymutilla velvet ants are sometimes known as “cow killers”, which is ridiculous as their sting is essentially harmless – apart from the pain.

Schmidt rated their stings between 2 and 3. He later described the sting of D. klugii females as causing “intense burning“, with “variable reactions” lasting 5–30 minutes.

Given that they don’t have stingers, males shouldn’t be able to sting. But they have found a way to fake it.

Sphaeropthalma arota, a velvet ant from California (Credit: Visuals Unlimited/NPL)

Sphaeropthalma arota, a velvet ant from California (Credit: Visuals Unlimited/NPL)

Unlike a lot of velvet ant researchers, Joseph Wilson of Utah State University Tooele in the US has never been stung by a female. But he has been stung by males.

There’s nothing that we have found that regularly eats velvet ants

“When you grab them they will aggressively poke you with the pointed parts of their genitalia,” says Wilson. “They can feel like little needles sticking into your finger.”

This fake sting can be enough to dupe a predator into letting a male go. “Generally, the pseudo-sting isn’t too painful but it can surprise you if you aren’t expecting it,” says Wilson.

Clearly, velvet ants are not insects to mess with. But it has proved surprisingly difficult to identify the predator that they are defending themselves from.

Collared lizards (Crotaphytus collaris) may eat velvet ants (Credit: Daniel Heuclin/NPL)

(Credit: Daniel Heuclin / NPL)

Lizards have long been the prime suspects. They are active at the same times and in the same locations as velvet ants, and they eat insects that are similar to velvet ants.

The velvet ants almost always escaped unharmed

In the 1980s, two biologists studying the diets of collared lizards in the southern US found velvet ants in the stomachs of two females. Once in a whileskinks and frogs have also been found to eat them. But such reports have been few and far between.

“There are some instances when potential predators will eat [velvet ants], but in general there’s nothing that we have found that regularly eats velvet ants,” says Wilson. He is currently trying to find out if western whiptail lizards eat them.

“There aren’t really any true or meaningful predators,” agrees Schmidt.

Dasymutilla gloriosa, and hairstyle (Credit: Joseph Wilson, Utah State University)

Dasymutilla gloriosa, and hairstyle (Credit: Joseph Wilson, Utah State University)

Schmidt could not identify any in his experiments. Ants, spiders, lizards and gerbils all attacked velvet ants, but the velvet ants almost always escaped unharmed.

Maybe their defences did not evolve to deal with predators after all

A tarantula and a gerbil did manage to eat one each, but that was it. Some predators gave up after one or two attempts and others after being stung, even though they habitually preyed upon stinging wasps and toxic ants.

In an intriguing experiment published in 2001, researchers dropped four velvet ant species into enclosures housing insect-eating Texas horned lizards. The lizards only ate the ones that looked like the harvester ants they normally eat, and ignored the rest.

That suggests velvet ants only get eaten by accident, by predators targeting the ants they resemble. So maybe their defences did not evolve to deal with predators after all.

Velvet ants look and smell scary, plus they squeak and sting (Credit: Barry Mansell/NPL)

Velvet ants look and smell scary, plus they squeak and sting (Credit: Barry Mansell/NPL)

Instead, it’s conceivable that they evolved to protect the velvet ants when they lay their eggs.

You’ve got to have enough defences so that you can make it through

After mating, a female velvet ant sets off alone to find the closed underground nests of solitary wasps or bees. These insects seal their larvae inside their burrows with some food, and never return. The velvet ant female breaks into the nest and lays an egg inside.

When the velvet ant larva hatches, it feasts on the larva, munching its way into its innards. It then pupates inside the nest and makes its way out as a fully-grown adult.

According to Schmidt, this “parasitoid” lifestyle is fraught with risk.

A female velvet ant approaches her host insect's nest (Credit: Kim Taylor/NPL)

A female velvet ant approaches her host insect’s nest (Credit: Kim Taylor/NPL)

“You have a pretty hard time finding your hosts, which are often widely dispersed,” he says. “If you are spending hundreds and hundreds of hours exposed, with people looking at you like, ‘oh yum, dinner’, you’ve got to have enough defences so that you can make it through.”

This is doubly true for velvet ants that, instead of targeting the undefended nests of solitary insects, break into the guarded nests of social wasps and bees.

These large nests are tempting targets, because they offer a lot of egg-laying opportunities in one place, but they are also more dangerous so only a few velvet ants tackle them.

One such species is Mutilla europaea.

A velvet ant from Tooele, Utah (Credit: Joseph Wilson, Utah State University)

A velvet ant from Tooele, Utah (Credit: Joseph Wilson, Utah State University)

It once targeted bumblebees, with great success. Records from the 19th century note instances when more velvet ants hatched from a bumblebee nest than did bumblebees. They also wreaked havoc in honeybee hives.

If the wasps do attack the velvet ant, its hardened shell protects it

Nowadays, M. europaea velvet ants are occasionally seen strolling into the nests of Polistes biglumis, a species of social paper wasp. They are there, not to lay eggs, but to eat – and they have picked an unusual diet.

These velvet ants suck the saliva from wasp larvae, without inflicting any visible damage upon them. “Larval saliva is highly nutritious,” says Maria Cristina Lorenzi of the University of Turin, Italy.

Lorenzi found that an M. europaea female can sneak around a paper wasp nest unobserved. That’s thanks to the chemical makeup of its outer shell, which has low concentrations of certain chemicals that cause the wasps to recognize and attack intruders. If the wasps do attack the velvet ant, its hardened shell protects it.

An unidentified velvet ant from Madagascar (Credit: Pete Oxford/NPL)

An unidentified velvet ant from Madagascar (Credit: Pete Oxford/NPL)

Clearly, velvet ants like M. europaea have good reason to evolve defences against the insects they are targeting. But that can’t explain the other defences, like colour mimicry and squeaking, which play no role in this.

That brings us back to the idea of predators and the threat they pose to velvet ants.

It seems to me like it might be kind of a fun life to be a velvet ant

“We think it’s just about predation,” says Wilson. “Maybe there’s an extinct predator, and these defences evolved in connection with some predator that we are not able to identify because it’s no longer here.”

Alternatively, it may be that velvet ants were faced with a multitude of predators, all using different strategies, so had to evolve a range of defences to safeguard against them all. “Different characteristics defend better against different predators,” says Wilson.

In that case, maybe the reason so few animals eat them is simply that their defences are effective. Evolution has pushed them to have so many defences that, nowadays, most predators target easier prey.

“They are such masters of life,” says Schmidt. “They really have figured [out] how to survive and do everything right. It seems to me like it might be kind of a fun life to be a velvet ant.”

There’s one last thing. For all that we have discovered about velvet ants, we have no idea about the most obvious question of all. Why are they so hairy?

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Pray for Pope Francis Has He Undergoes Surgery : President Buhari

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Roman Catholic church head, Pope Francis has undergone surgery hours after attending the traditional Sunday Angelus prayer in St. Peter’s Square on Sunday, July 4.

President Muhammadu Buhari has sent a get-well message to the Head of the Catholic Church, Pope Francis, as he heads in for a scheduled surgery of the colon.

The president’s Senior Special Assistant on Media and Publicity, Malam Garba Shehu, confirmed this in a statement in Abuja on Sunday.

Buhari called for prayers from Nigerians and the global community as the Pontiff goes in for this routine operation.

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Twitter CEO, Jack Dorsey reveals special #EndSARS emoji after endorsing the movement

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Twitter CEO,  Jack Dorsey has revealed special #EndSARS Emoji after endorsing the movement against police brutality and other unlawful crimes in Nigeria.

Jack tweeted his support for the #EndSARS protests and called for Bitcoin donations towards the movement two days ago.

Last night, Twitter experienced issues globally with large numbers of users unable to post tweets, access their timelines, or see notifications. After fixing these issues, Jack Dorsey revealed a special #EndSARS emoji, a fist with the colour of the Nigerian flag.

Nigerians have flooded his comment session to thank him for his support and the special #EndSARS emoji he created for the movement.

Twitter CEO, Jack Dorsey reveals special #EndSARS emoji after endorsing the movementTwitter CEO, Jack Dorsey reveals special #EndSARS emoji after endorsing the movementTwitter CEO, Jack Dorsey reveals special #EndSARS emoji after endorsing the movementTwitter CEO, Jack Dorsey reveals special #EndSARS emoji after endorsing the movement

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Brazilian footballer Neymar faces fresh police questioning over claim he raped a model in Paris hotel room

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Brazilian footballer, Neymar, 26, will be questioned for the second time over claims he raped a model in a Paris Hotel room.

The Paris Saint-Germain star has reportedly agreed to fly into São Paulo in Brazil to meet with detectives over the alleged rape attack on 26-year-old model, Najila Trindade Mendes de Souza. 

Speaking to MailOnline, Dr. Juliana Lopes Bussacos, the officer in charge of the investigation, said: ‘He will be treated like any other citizen. He has the same rights as any other man.

‘I have interviewed many men in these situations and everyone is equal and they all have the right to tell their story and produce evidence to back it up.’

With detectives desperate to get to the bottom of what happened,  Dr. Juliana said she couldn’t enter into details of the rape accuser’s complaint due to confidentiality.

‘There are so many questions and answers that need clarification. He says he did not rape her and she has said she has evidence.

The former Barcelona striker is expected to give his statement in the next 48 hours, and then officers will decide if there is a case and if it is necessary to bring them together.

This comes after it was revealed that Neymar could be cleared of the rape accusation levied against him within days over lack of more evidence from his accuser.

The Brazilian model has been informed by her lawyer that she faces seeing her case against the Paris Saint-Germain star dropped except there is more evidence. She also faces losing the second lawyer to represent her after he said he could not carry on if his professional ‘trust’ in her was compromised.

Trindade’s attorney Danileo Garcia de Andrade said he still believed Ms. Trindade had a case, but he would step aside if there was a lack of evidence.

Mr. Daileo said he had given her a deadline to produce the video and photographs she claimed to have had which would help prove her allegations of rape against the Brazilian superstar. But if the evidence was not forthcoming, he said, he would drop the case next week.

Mr de Andrade told Brazil’s UOL Esporte: ‘If the police investigation of the supposed break-in where she lives shows there was no break-in, I am leaving the case.’

He added: ‘The attorney-client relationship is based always on trust. If there is no trust, then there is no reason to stay on’

Trindade claimed she was the victim of ‘aggression and rape’ by the Paris Saint-Germain player in a hotel room in the French capital on May 15. She said the encounter started out consensual but quickly turned violent, leaving her with bruises and scrapes to her legs and buttocks, with Neymar refusing to stop.

She told police her tablet containing a seven-minute video, messages and photos she alleged incriminated the footballer, was stolen in a burglary at her apartment. But the authorities said they found no major signs of a break-in and only Ms. Trindade’s fingerprints and those of her maid and friends around the flat.

Neymar has strongly denied raping her but admitted that what happened between them was consensual.

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