Scientists recreate the song of long-lost insect to help find it again
After 150 years sitting silently in a museum, a strange specimen has now sung its song once more. Scientists have digitally recreated the sound of a long-lost species of insect, not seen since 1869, by creating 3D scans of its wings. The specifics of the tune could help track down living specimens in the wild – if there are any left.
Prophalangopsis obscura is a species of katydid, a grasshopper-like insect, but not much is known about it because only a single specimen has ever been collected. The lonely holotype, a 10-cm-long (4-in) male, was recovered from somewhere in India in the mid-19th century, before being donated to the London Natural History Museum where it was first scientifically described in 1869.
And it hasn’t been seen since, despite scientists’ best efforts. The closest match may have come from a 2009 paper describing two female katydids found in Tibet that look suspiciously similar to the solo P. obscura specimen, but because of differences between the sexes it’s impossible to tell whether they’re from the same species or a closely related one.
Now, a team of scientists has found a unique way to help the search. Like their cricket relatives, katydids are known to rub their wings or legs together to make noise that attracts mates. So the researchers scanned the wings of the specimen, created 3D images of their surface structure, and figured out their resonant frequency.
From that, they were able to determine that it produces a pure-tone song, around a frequency of 4.7 kHz. They then reproduced the insect’s song digitally. Have a listen below:
It might sound similar to any cricket you’d expect to hear on a warm summer night, but from that song the scientists can actually infer quite a lot of information about where the insect might be found, if any still exist in the wild.
The sound is a low pitch, which helps carry it a long distance. That’s great for finding mates, but also great for attracting predators like bats. The fact that this species is one of just a few that have survived relatively unchanged since the Jurassic era indicates it hasn’t had to evolve defenses against bats.
“Comparing this species to modern relatives is interesting because it has large wings, which suggest it is capable of long flight, and sings a low-pitched song which travel over long distances,” said Ed Baker, co-author of the study. “Along with its habit of living out in the open, these features should make it an ideal target for bats as it is easier to detect. Its survival since the Jurassic suggests that it currently lives in an environment without bats that feed on free-flying insects.”
As such, the team suggests focusing future searches to regions of North India and Tibet that are too cold for bats. And now that we have a better understanding of what P. obscura might sound like, the researchers say it could be a good idea to set up recording equipment to try to listen out for these calls, which could lead to the rediscovery of the species.
The research was published in the journal PLOS ONE.
Source: Natural History Museum