Natures wonders: insect uses resin to catch prey (Introduction)

by David Turell , Friday, May 12, 2023, 23:23 (349 days ago) @ David Turell

A sticky substance holds the prey long enough to kill:

https://www.sciencealert.com/scientists-discover-a-rare-example-of-insects-using-tools-...

"In Australia, assassin bugs use a lethal tool to ensnare snacks: resin from spinifex grass. Recent research shows that the crawly critters slather themselves in the gluey gum to catch and keep their prey.

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"The authors say this makes assassin bugs "a particularly promising case for understanding the ecological and behavioral conditions that facilitated the otherwise unlikely evolution of tool-use."

"Because tool use requires a level of complex cognition, it was once thought to be a way to set humans apart from other animals, but researchers are now finding more and more examples of tool use across the animal kingdom.

"Humans were even using tools before our thumbs fully developed dexterity, and it seems the earliest tools were not even human-made. Dolphins protect their beaks with sea sponges, pigs use sticks, and even brainy birds and bees are in on it.

"Scientists had a hunch that assassin bugs' hunting success would increase if they coated themselves in the sticky resin of plants, but this had not been tested in experiments.

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"The researchers put the insects in a glass jar with a stick and introduced two kinds of prey: flies and ants. Then they used makeup removal pads to carefully wipe the resin off the insects' bodies, and the experiment was repeated.

"The bugs were generally more successful at catching ants than flies, and importantly, they were more effective at catching prey when they had resin on their bodies, regardless of the type of prey.

"Resin-covered insects were 26 percent more successful at capturing either type of prey than their unarmed counterparts. Flies are tricky to catch even on a good day, and without resin, 64 percent of the flies that Gorareduvius touched got away."

Comment: the insects live in this resin-producing grass. How much is accidental and how much is instinct is not clear. The authors don't describe the insects rubbing them themselves all over with resin.