Scientists have been puzzled over the purpose of the Tiger Moth’s tymbal organ membrane, which is able to vibrate at ultrasonic frequencies. The consensus is that it serves as a warning to bats, since the moths are able to retain poisons harvested from host plants. Scientists believed the moths who were poisonous were warning the bats, and those that weren’t were faking it anyways.

New experiments by Aaron Corcoran of Wake Forest University, however, have confirmed another theory: the moths are actually using the fast paced clicking to jam the bats’ echolocation. It is the first evidence of sonar jamming in nature:

Normally, a bat attack starts with relatively intermittent sounds. They then increase in frequency—up to 200 cries per second—as the bat gets closer to the moth “so it knows where the moth is at that critical moment,” Corcoran explains. But his research showed that just as bats were increasing their click frequency, moths “turn on sound production full blast,” clicking at a rate of up to 4,500 times a second. This furious clicking by the moths reversed the bats’ pattern—the frequency of bat sonar decreased, rather than increased, as it approached its prey, suggesting that it lost its target.

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From the Upcoming ueue, submitted by coconutnut.

Caterpillars of the Great Peacock Moth (Saturnia pyri) are making quite a buzz. A recent study has shown that these giant silkmoth caterpillars are advertising acoustically that they are unpallatable and warn of an upcoming defense strategy.

When disturbed by a would be attacker the caterpillars stridulate by rubbing their mouth parts together, creating broadband chirps spanning from 3.7-55.1 kHz. While it is still unclear who exactly they are advertising to, a predator would be well advised to stay away from their sharp, chemical exuding bristles.

Though is not the first example of sound production in caterpillars it is a novel mechanism, paving the way for future research. (Photo: V. Bura)

Saturnia pyri chirp before or while they ooze foul-smelling droplets from their bristles. So the chirps might be a warning to attackers that there’s some serious resistance on the way, Yack and her colleagues propose online and in an upcoming Naturwissenschaften.

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From the Upcoming ueue, submitted by afleming.

Moths that fly high above our heads throughout the night are not at the mercy of the wind but use a sophisticated internal compass which can help them travel up to 400 miles in a single flight . . . While it is not clear how the creatures – in this case, the Silver Y moth – actually navigate between sunset and sunrise, researchers from the UK and Germany have found that the insects can judge the best conditions for flight based on direction and windspeed, selecting the fastest moving layers of atmosphere so, with their own speed of 10mph, can cruise at speeds of up to 55 mph.

In other words, moths are smarter and faster than many of us have imagined.

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(Image by Everything is Permuted)