Bats and moths have been engaged in acoustic warfare for more than 60 million years.
Yet almost half of moth species lack bat-detecting ears and still face intense bat predation.
Now a group of researchers have hypothesized that the long tails of one group of seemingly defenseless moths, saturniids, are an anti-bat strategy designed to divert bat attacks.
Using high-speed infrared videography, they showed that the spinning hindwing tails of luna moths lure echolocating bat attacks to these nonessential appendages in over half of bat–moth interactions. They also proved that long hindwing tails have independently evolved multiple times in saturniid moths.
Moth tails lured bat attacks to these wing regions during 55% of interactions between bats and intact luna moths.
After analyzing flight kinematics of moths with and without hindwing tails, the researchers found that tails have a minimal role in flight performance.
Using a robust phylogeny, we find that long spatulate tails have independently evolved four times in saturniid moths, further supporting the selective advantage of this anti-bat strategy.
Diversionary tactics are perhaps more common than appreciated in predator–prey interactions. The findings of the scientists, who presented their week last month in Proceedings of National Academy of Sciences
Moth tails lured bat attacks to these wing regions during 55% of interactions between bats and intact luna moths. We analyzed flight kinematics of moths with and without hindwing tails and suggest that tails have a minimal role in flight performance. Using a robust phylogeny, we find that long spatulate tails have independently evolved four times in saturniid moths, further supporting the selective advantage of this anti-bat strategy.
Diversionary tactics are perhaps more common than appreciated in predator–prey interactions. Our finding suggests that focusing on the sensory ecologies of key predators will reveal such countermeasures in prey.
Boise State biologist Jesse Barber, a coauthor of the paper, along with scientists at the University of Illinois in Urbana-Champaign said in an interview in Txchnologist that looking at evolutionary history showed the tails had lengthened.
“It’s remarkable that hindwing tails have independently lengthened to spectacular proportions four times throughout the evolutionary history of the Saturniidae family of moths.
The findings expand human knowledge of the portfolio of strategies animals use to survive predator attack which might also offer new insights into sonar development by the military.
h/t: Txchnologist , PNAS
