The good thing to be a frog is that you don’t have to chew your food – just sipand down the hatch. The problem with the frog is that you don’t have to chew your food, which means that if you happen to bite the water beetle Regimbartia attenuata, your food can come out the other end in an unwanted way: alive and literally kicking.
Write in the diary today Current biology, Kobe University ecologist Shinji Sugiura describes how the beetle, enclosed behind the frog’s jaws, turns and sneaks through its digestive tract. In carefully designed laboratory experiments, Sugiura found that 93 percent of the beetles he fed the frog Pelophylax nigromaculatus escaped from the predator̵
Apparently they understand their unique difficulty, The R. weakened the beetles seem to have slipped through the frogs’ intestines. Sugiura showed so much by immobilizing some of the beetles’ legs with wax – this time none of them came out of the anus alive, but like feces, for more than 24 hours. It all came as a surprise to Sugiura himself. Given that the predator and prey share a habitat in Japan’s rice fields, he speculated that the beetle may have developed some protection against the frog. “However, I did not foresee it R. weakened can escape the frog, “Sugiura wrote in an email to WIRED.” I just gave a beetle to the frogs, expecting the frogs to spit them out in response to the beetles’ behavior or something. “
It may be imperceptible that the adaptations that the beetle has already evolved for aquatic life have prepared it for the great journey through the frog’s digestive system. On the one hand, these insects swim quite effectively, kicking their legs, so that they may actually be swimming through the waste in the frog’s intestines. Insects also breathe through holes in their hard shells or exoskeletons. To breathe underwater, this particular species of beetle captures a small pocket of air under its wings, which are known as elytra. (Think of the regimental scales that the ladybug opens to remove.)
Maybe he does the same while finding his way through the inside of a frog. “I would imagine that an air bubble would help the beetle breathe and could provide a small jacket to keep stomach acid at rest while it escapes,” said Christopher Grinter, an entomology manager at the California Academy of Sciences who was not does not participate in the study.
But how does the beetle make the frog open the hatch? “Further experiments are needed to study how to simulate frogs for defecation,” says Sugiura. “It simply came to our notice then R. weakened use the legs and body to simulate the frog’s hindgut. “What it may feel like for a frog is someone’s guess.
Still, things can be much worse for the predator: Beetle larvae Epomis are more active in humiliating frogs. When a frog approaches one of these larvae, the “prey” sinks its jaws attached to the “predator’s” tongue, releasing enzymes that melt its flesh. The larvae lock in there, absorbing the eliminated nutrients from the amphibians. After a few days, the frog is so weak that it can no longer move. Finally, “what we are seeing is that it is tearing tissue from the body of amphibians,” entomologist Gil Wiesen told WIRED a few years ago. “After a few hours, the amphibians are reduced to a pile of bones and some skin.”
Indeed, frogs cannot fail to feed – sometimes the beetle ends up through its digestive system and appears alive, and sometimes the beetle consumes the frog alive. “Frogs are voracious predators, forming an indispensable role in food webs and most ecosystems,” said amphibian biologist Jody Rowley of the Australian Museum, who was not involved in the study. “It would be interesting to see if the frogs avoid eating these beetles in the wild, or if they continue to eat them, with a random beetle that fails to escape, making everything useful.”
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