The beautiful Being a frog means you don’t have to chew your food – just Sipand down the hatch. The problem with being a frog is that you don’t have to chew your food, which means you snatched the water beetle Regimbartia attenuata, Your food could come out on the other end in an undesirable way: alive and literally kicking.
Write in the magazine today Current biologyKobe University ecologist Shinji Sugiura describes how the beetle trapped behind the frog’s jaws turns and crawls through its digestive tract. In carefully elaborated laboratory experiments, Sugiura found that 93 percent of the beetles he fed the frog Pelophylax nigromaculatus escaped the predator̵
Apparently they understand their unique location R. attenuata Beetles seem to have climbed through the frogs’ guts. Sugiura demonstrated this by rendering some of the beetle legs motionless – this time none of them emerged alive from the anus, but over 24 hours later as feces. All of this was a surprise for Sugiura. Given that predator and prey live together in Japan’s rice fields, he hypothesized that the beetle might have developed some form of anti-frog defense. “However, I did not predict that R. attenuata can escape from the frog slot, ”Sugiura wrote in an email to WIRED. “I just provided the frogs with the beetle and expected the frogs to spit them out in response to the behavior of the beetles or something.”
Coincidentally, the adaptations the beetle had already developed for aquatic life prepared him for the long journey through a frog’s digestive system. For one, these insects swim quite effectively by kicking their legs. Maybe they actually swim through the garbage in the frog’s gut. Insects also breathe through holes in their hard shells or exoskeletons. To breathe underwater, this particular species of beetle captures a small air bubble under its wing covers, known as the Elytra. (Think of the dotted flaps that a ladybug opens to take off.)
Perhaps it does the same as it finds its way through a frog’s innards. “I would imagine an air bubble to make it easier for the beetle to breathe and possibly provide a small jacket to keep stomach acid at bay while escaping,” said Christopher Grinter, entomology collection manager at the California Academy of Sciences involved in research.
But how does the beetle get the frog to open the hatch? “More experiments are needed to investigate how the frogs can be simulated to defecate,” Sugiura says. “However, I speculate R. attenuata Use legs and body to simulate the frog’s hind gut. “How that might feel for the frog is unclear.
However, things could get much worse for the predator: the larvae of the beetle genus Epomis are more active in humiliating frogs. When a frog approaches one of these larvae, the “prey” sinks its hooks into the tongue of the “predator” and releases enzymes that melt its meat. The larvae lock themselves in there and absorb the liquid nutrients of the amphibian. After a few days, the frog is so weak that it can no longer move. Finally, “we see it tear tissue out of the amphibian body,” entomologist Gil Wizen told WIRED a few years ago. “After a few hours, the amphibian is reduced to a bunch of bones and just a little bit of skin.”
Really, frogs can’t help but eat – sometimes the beetle experiences adventure through its digestive system and emerges alive, and sometimes the beetle consumes the frog alive. “Frogs are insatiable predators that play an irreplaceable role in food webs and most ecosystems,” said Australian Museum’s amphibian biologist Jodi Rowley, who was not involved in the research. “It would be interesting to see if the frogs avoided eating these beetles in the wild or if they continue to eat them with the occasional beetle that fails to escape, which makes everything worthwhile.”
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