MONS, Belgium, June 20 (UPI) -- New research has revealed the chameleon's secret weapon -- saliva 400 times stickier than human spit. The lizards use their saliva-soaked tongues to zap unsuspecting insects.
Researchers knew chameleons used their tongues to take down grasshoppers, flies and other prey. They also knew the chameleon's tongue doesn't wrap around its prey.
Scientists from the University of Mons in Belgium decided to see how the tongue of a chameleon was so adhesive. Their study is the first to examine the viscosity of the mucus produced by the chameleon's tongue.
Led by physicist Pascal Damman, a team of researchers waited patiently for a captive veiled chameleon, Chamaeleo calyptratus, to smack its tongue against a clean slab of glass, behind which scientists had placed several juicy crickets. The researchers then took the saliva sample to the lab for analysis.
What they collected from the glass was as thick and sticky as honey.
The researchers measured the saliva's adhesiveness by coating a bead in it and rolling it along a slanted glass plate. This allowed the scientists to measure how much the saliva slowed the bead's acceleration down a decline.
The lizard's tongue is made a more effective weapon by the speed at which it accelerates and retracts. As it hits the prey, the tongue's tip makes a tiny suction cup-like shape that helps to grab the fresh meal.
"When the tongue pulls rapidly, it makes the adhesion higher," Damman told National Geographic.
The new research was published in the journal Nature Physics.