Gruesome footage has revealed how bombardier beetles cause toads to vomit them up after being eaten alive.
These remarkable beetles eject 100°C (212°F) toxic chemicals from their abdomen into the toad’s stomach, causing them to regurgitate their meal.
Researchers found that 43 per cent of beetles in their study were able to escape unharmed from the digestive juices of the toad’s stomach within 12 to 107 minutes.
Scientists believe this beetle has also developed greater tolerance to toad digestive juices, meaning it can survive while it’s waiting for the toad to vomit.
Plucky little bombardier beetles eject 100°C chemicals from their abdomen after being eaten by toads (pictured) in order to force the amphibians to throw them up
Experts led by Kobe University found the bombardier beetle, scientific name Pheropsophus jessoensis, discharged boiling chemicals called quinones and water vapour.
They studied a toad, a species of the Bufo genus, who ‘readily swallowed the beetle’ under lab conditions.
On average, the toad vomited the beetle 44 minutes after swallowing it and the regurgitated beetle was still alive and active, researchers found.
‘All toads avoided the bombardier beetles just after vomiting them’, lead researcher Dr Shinji Sugiura from Kobe University told MailOnline.
‘Therefore, toads can learn the body colour and shape of bombardier beetles, although some toads may have a poor memory.’
Bombardier beetles have two separate sections that contain chemicals that are harmless on their own, but when they react together have a devastating effect.
When threatened, the beetles can force the chemicals into the same chamber of their body.
This starts a series of events that involves enzymes, hydrogen peroxide and chemicals called hydroquinones.
Hydrogen peroxide breaks down into boiling water and gas, whilst the hydroquinones break down into benzoquinones.
Forty-three per cent of beetles escaped from the digestive juices of the toad’s stomach between 12 to 107 minutes, according to the study. Pictured is a toad about to swallow a beetle
These are highly irritating chemicals that have been known to stain human skin and irritate the eyes.
When these chemicals come together, a large amount of energy is released which vaporises some of the liquid as well raising its temperature to around 100°C (212°F).
Toads have to invert their stomachs to vomit, which is why it takes such a long time for them to regurgitate the beetle.
Only a few animals escape from inside amphibians, probably because strong acids kill most prey in their stomachs shortly after they are swallowed.
‘The bombardier beetle species may have evolved a high tolerance for toads’ digestive juices’, Dr Sugiura added.
Remarkably, they were all alive and well after their ordeal, researchers found. Scientists believe this beetle has also developed greater tolerance to toad digestive juices meaning it can survive while it’s waiting for the toad to vomit
They studied a toad, a species of Bufo, who ‘readily swallowed the beetle’ under lab conditions. On average the toad vomited the beetle (pictured) 44 minutes after swallowing it and the regurgitated beetle was still alive and active, researchers found
It’s also possible, however, that the chemical secretions from the beetle reduced the potency of the toads’ digestive fluids and enzymes.
This would mean the toad’s stomach was less well equipped to kill the beetle.
Researchers found large beetles escaped more frequently than small beetles, and small toads vomited the beetles more frequently than large toads.
They believe this could be because large beetles can eject more defensive chemicals and small toads have a lower tolerance to toxins.
Bombardier beetles (pictured, left) have two separate sections that contain chemicals that are harmless on their own, but when they react together have a devastating effect. When threatened, the beetles can force the chemicals into the same chamber
WHAT ARE BOMBARDIER BEETLES?
Bombardier beetles are found all over the world on every continent except Antarctica.
In the US alone, there are more than 40 species of bombardier beetle.
They thrive in temperate locations and are often found in woodlands and grasslands.
There are hundreds of different species of bombardier beetles around the world and they all tend to be small, no larger than 2.5 cm (one inch) in length.
They tend to have blue wing coverings and a red head and limbs.
Bombardier beetles are found all over the world on every continent except Antarctica
Populations of the beetles are very stable and they are not thought to be a conservation concern.
The beetles are carnivorous (even the larvae) and their diet consists predominantly of small insects.
They tend to hunt at night and when they are not looking for food, they tend to gather in small groups with others of their species.
Bombardier beetles have a unique ability to shoot a corrosive, boiling chemical spray at potential predators.
The beetles have two separate sections that contain chemicals that are harmless on their own, but when they react together have a devastating effect.
When threatened, the beetles can force the chemicals into the same chamber.
This starts a series of events that involves enzymes, hydrogen peroxide and chemicals called hydroquinones.
The hydrogen peroxide breaks down into boiling water and gas whilst the hydroquinones break down into benzoquinones – highly irritating chemicals that have been known to stain human skin and irritate the eyes.
When these come together, a large amount of energy is released and vaporises some of the liquid as well raising the temperature to around 100°C (212°F).
This huge increase in pressure forces the noxious, pungent chemical out of a small outlet at the tip of the abdomen.
Some African bombardier beetles can even rotate the tip up to 270 degrees to better aim the spray of the potent chemical.
‘Our results demonstrate the importance of the prey–predator size relationship in the successful escape of prey from inside a predator’, researchers wrote in a paper outlining their findings.
More than 600 species of bombardier beetles can discharge the hot chemicals.
However, this is the only species to have been seen to successfully use the spray to escape from the inside of a predator.
‘Successful escape from predators’ digestive systems has been reported in several animal species: a blind snake from a toad, adult diving beetles from a toad, a carabid beetle larva from a frog, horsehair worms from fishes and frogs and land snails from birds’, researchers wrote.
‘However, the ecological factors determining successful escape remain unexplored.
‘We showed that the bombardier beetle P. jessoensis ejects toxic chemicals inside the toad, thereby forcing the toad to vomit’, they wrote.
The full results of the study were published in the journal Biology Letters.