Size doesn't matter: Tiny insect that sings with its penis is loudest creature on Earth



A tiny insect has proved that size really doesn't matter - by using its penis to become the loudest creature on Earth.

Most would think the 2mm long water boatman would not have much to shout about, seeing as its private parts are thinner than a human hair.

But its looks have proved deceiving as it can reach an ear-splitting 99.2 decibels by rubbing its penis against its abdomen - which, relative to its body size, makes it the most boisterous bug on the planet.

Loud and proud: The water boatman is, pound for pound, the noisiest animal on the planet

The water boatman, or Micronecta scholtzi, has been dubbed 'the singing penis' for the way it serenades potential mates.

Found all over Europe, the male tries to seduce prospective partners by rubbing its member against its abdomen, while underwater, in a process known as stridulation.

It is so loud that humans walking along a river bank can hear the noise coming from the bottom of the water.

But as 99 per cent of the sound is lost when transferring from water to air, it means there is no risk of deafening passers-by.

TOP 10 NOISIEST ANIMALS

1. Blue Whale

2. Howler Monkey

3. Grey Wolf

4. Elephant

5. Hyena

6. Lion

7. Bulldog bat

8. Kakapo bird

9. Elephant Seal

10. U.S. Bullfrog

Their average song reaches 78.9 decibels, the same as a passing freight train.

Blue whales are the loudest animals when they sing at 188db, while the rumbling calls of elephants' clock up an impressive 117db.

But at just 2mm long, the water boatman is the noisiest animal on Earth - once body size is taken into account.

French and Scottish scientists made the startling discovery.

Researcher Jerome Sueur, from Paris' National Museum of Natural History, was analysing the biodiversity of French streams when he heard the distinctive underwater call.

At first he believed a much larger insect was responsible for the racket, but when he caught them they did not make the same sound.

Further investigation revealed it was a particular type of water boatman that was 'singing' its heart out.

James Windmill, of the University of Strathclyde in Glasgow, said: 'We were very surprised. We first thought the sound was coming from larger aquatic species.

'When we identified without any doubt the sound source, we spent a lot of time making absolutely sure that our recordings of the sounds were calibrated correctly.

'If you scale the sound level they produce against their body size, then they are the loudest animals on Earth.'

Penis serenade: The water boatman is so noisy it can be clearly heard from the bottom of a river

And as professor at the Centre for Ultrasonic Engineering, Windmill said the bugs were 'very interesting' to engineers.

He said a typical sonar array emitted pulses of sounds and then listend back for echoes. A machine the size of a person was needed to make the noise.

This was in stark contrast to the water boatmen who are only 2mm long.

Their findings were published in the science journal PLos One, which said: 'This insect is a few millimetres in length yet can produce sound audible from the riverside.'

It reported that the bugs did not appear to have any predators which would find them via their call, and so there was no evolutionary need for them to quieten down.

But it added they did not know why the sound was so loud, and that observing the micro-mechanics of such a small animal would be very difficult.