There's a bit of science behind frogs slurping up their prey. In just one slimy swoop, these creatures can grab up some grub, sometimes even larger than themselves.
A new study published in Scientific Reports explains just how the horned frog uses this feeding apparatus to cleverly cement and capture new prey.
In general, frog tongues produce about one-fifteenth theadhesive strength of the feet of a gecko, another incredibly sticky creature.
"However, in terms of prey capture, frog tongue adhesive forces are enormous-on average 1.4 times their body weight," said Thomas Kleinteich and Stanislav Gorb, via National Geographic. "Translated into human dimensions," he said, "that would be an 80-kilogram [176-pound] person lifting 112 kilograms [246 pounds] just by using his or her tongue. And they do this within milliseconds" of making contact.
As frog tongues typically secrete a wet mucus, many may mistake the creature's slimy tongue that leaves a shiny surface behind as a type of "cement" that enforces the capturing of its prey.
"People tend to think that the mucus acts as some sort of superglue," said Kleinteich. "But our results suggest that less mucus results in better adhesion."
For the study, researchers found that the longer the creature's tongue was against a glass window before snapping back, the more mucus was secreted. Yet their tongues were still able to catch up to so-called pressure-sensitive adhesives. However, the "sticking power" was also dependent on how hard the tongue hit the glass and how big an area it covered. The highest impact tongue smack would also allow the strongest pulling forces but also much less mucus and better adhesion, at the same time.
Furthermore, researchers found that, on average, the force of the frog's tongue exceeded its body mass by about 50 percent.
"I knew these frogs could eat large things," Kleinteich added, via The Los Angeles Times "but I didn't really expect that the forces would be that high."
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