Chameleons have a super-slimy secret.
Despite their size, these old-world lizards are vicious predators that hunt mice, grasshoppers, flies, birds and even other chameleons. And it's all thanks to their ultimate weapon: their lightning-fast tongue.
This animal's tongue has been extensively studied in recent years, with experts discovering that chameleons never wrap their tongue around their meal.
So how does the chameleon's tongue hold on to prey while pulling it toward their mouth at such high speed?
The Chameleon's Tongue As An Adhesive
Multiple explanations have been proposed by biologists in the past. Some say the mechanism behind it is stickiness, suction or even a Velcro-like bond between the lizard's tongue and its meal.
But now, new research conducted by scientists in France and Belgium revealed the answer: the chameleon's tongue produces saliva that is about 400 to 1,000 times more viscous and stickier than human saliva.
In fact, this ultra-thick mucus actually helps chameleons take down and ensnare prey -- even those that are a third of their own weight.
Pascal Damman, co-author of the study and a physicist from University of Mons in Belgium, said they were surprised to see how viscous the liquid or saliva is. He said this is the first time that the thickness or viscosity of chameleon has been studied.
"The simplest explanation [is] the best one," said Damman.
Tip Of The Tongue
In order to calculate the adhesive properties that the saliva would convey, Damman and his colleagues used mathematics.
They waited patiently for a captive veiled chameleon to dab its tongue against a slab of glass. Behind the glass, the researchers placed several crickets.
Afterwards, they collected the saliva sample and analyzed them at the lab. The saliva sample was as thick and sticky as honey, study authors said.
Damman and his colleagues covered a bead in the chameleon spit and rolled the bead on a slanted glass plate. This helped them assess how much the saliva slowed the bead's acceleration.
Indeed, researchers said as the chameleon's tongue hits its prey, a tiny suction cup-like shape on the tip of the tongue helps the animal grab the meal. And when the tongue snaps faster, the adhesion becomes higher.
Meanwhile, researchers said the same sticky saliva is possibly present in other animals such as toads, frogs and salamanders that use their tongue to fetch their prey.
Details of the new study are featured in the journal Nature Physics on June 20.
Watch the video below.
Photo: Matt Reinbold | Flickr