Researchers have discovered that the native long-tailed stonefly species in New Zealand is forced to change its body color to survive in heavily deforested areas.
Zelandoperla stoneflies once had a clever strategy to evade predatory birds by mimicking the appearance of a relative, the Austroperla stonefly. The Austroperla species primarily inhabits dense forests and warns potential predators by secreting cyanide toxins.
Black Zelandoperla stonefly (center) camouflaged to resemble Austroperla stonefly (left) to avoid predators, and evolved to a brighter color (right) to adapt to a new environment – (Photo: University of Otago)
Although non-toxic, Zelandoperla stoneflies can convincingly mimic the appearance of Austroperla stoneflies by utilizing their genetic toolkit, allowing some insects to develop a color similar to ebony.
This camouflage helps them evade predatory birds, as the birds cannot distinguish between the toxic and non-toxic stoneflies.
However, a recent study by a team from the University of Otago in New Zealand revealed that Zelandoperla stoneflies in deforested areas have adopted a different survival strategy.
“Austroperla thrives in forests, near streams, feeding on leaves and decaying wood. In devastated forests, Austroperla becomes less common due to a lack of food sources. To survive, Zelandoperla stoneflies must abandon their mimicry of Austroperla and instead evolve into a different color,” said zoologist Jon Water.
According to ScienceAlert on November 11, the research team combined field observations, predation experiments, and genetic mapping analysis to demonstrate how this insect species responds to human-induced changes.
In experiments with Zelandoperla models of different colors, the team found that predatory birds only targeted the non-camouflaged stoneflies in dense forest environments. In deforested areas, they sought out lighter-colored stoneflies less frequently compared to the ebony-colored ones.
This research was published in the journal Science.
