Glue arms, baby. Glue arms.
There's an assassin on the loose in Australia — but not the kind you might be thinking.
As detailed in a recent study published in the journal Biology Letters, scientists have discovered a new type of tool-wielding insect, nicknamed the "assassin bug" for a creative — and deadly — hunting technique in which it meticulously coats itself in a sticky resin as a means of more effectively catching prey.
Per the study, the assassin bug uses a specific resin from a native Australian grass called spinifex grass.
"Tool use in animals is a complex and rare phenomenon, particularly in insects," reads the scientists' research. "Tool use in assassin bugs has been suggested as several species apply adhesive plant resins to their body, which has been hypothesized to function in enhancing prey capture."
Deadly glue arms? Check. Watch out, flies.
To test the extent of the tiny assassins' tool use, the Australian researchers observed the bugs in the wild as well as in captivity, taking 26 different assassin bugs from the outdoors and placing them in a glass jar with one of two prey: flies or ants.
As ScienceDirect notes, flies are particularly difficult to catch. Per the study, the resin-covered assassin bugs had a much easier time catching flies than their glueless counterparts did — of the 26 bugs, those with resin were 26 percent more successful at snagging the pesky winged prey.
"Here, we staged predatory interactions of resin-deprived and resin-equipped assassin bugs (Gorareduvius sp.) and discovered that applying resin as a tool conveys a clear predatory advantage to the assassin bugs," reads the study. "Gorareduvius sp. can thus be considered a tool-user, and since this behaviour was present in all individuals, including newly hatched nymphs, tool-use can be considered to be stereotyped."
And apparently, according to the scientists' observations, the use of the spinifex resin isn't a learned behavior, as even newly-hatched nymphs were seen coating themselves in the glue-like substance.
Innate tool use in an insect? That's pretty cool.
"Assassin bugs manipulated an environmental item (the resin), by taking it out of its usual context and applying it onto their bodies," the researchers concluded, "Thus gaining a selective advantage through improved prey capture."
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