After 150 years spent in silence in a museum, a strange specimen has once again sung its tune. Scientists have digitally recreated the sound of an insect species that has been extinct since 1869, by making 3D scans of its wings. The specifics of this melody could help find living specimens in the wild, if any remain.
Header image: artistic representation of the Prophalangopsis obscura, an insect which is only known from a single specimen collected 150 years ago. (Charlie Woodrow)
Prophalangopsis obscura is a species of grasshopper (Tettigoniidae), but not much is known about it, as only one specimen has been collected. The solitary holotype, a 10cm long male, was found somewhere in India in the mid-19th century, before being donated to the Natural History Museum in London, where it was first described scientifically in 1869.
The specimen of P. dark of the Natural History Museum is the only confirmed member of its species. (The Trustees of the Natural History Museum, London)
He has not been seen since, despite the best efforts of scientists. Perhaps the closest match came from a study in 2009 describing two females found in Tibet that look suspiciously similar to the solo specimen of P. darkbut because of the differences between the sexes, it is impossible to determine whether they are the same species or a closely related species.
Now a team of scientists has found a unique way to help research. Like their cricket cousins, Tettigoniidae are known to rub their wings or legs together to make a noise that attracts mates. The researchers therefore scanned the wings of the specimen, created 3D images of their surface structure and determined their resonant frequency.
From this they were able to determine that it produces pure pitch singing, around a frequency of 4.7 kHz. They then digitally reproduced the insect’s song.
From the study: the reconstructed call song of the Prophalangopsis obscura. (Woodrow et al./ PLOS ONE)
This song may sound like the song of a cricket you’d expect to hear on a hot summer night, but scientists have been able to deduce some information about where this cricket can be found. insect, if any still exist in nature.
The sound is serious, which makes it possible to carry it for a long distance. This is great for finding mates, but also for attracting predators like bats. The fact that this species is one of the few to have survived unchanged since the era Jurassic indicates that it did not have to develop defenses against bats.
According to study co-author Ed Baker:
Comparison of this species with related modern species is interesting, as it has large wings, suggesting it is capable of long flight, and it sings a deep song that allows it to travel long distances. With its habit of living in the open, these characteristics should make it an ideal target for bats, as they are easier to detect. Its survival since the Jurassic suggests that it currently lives in an environment free of bats that feed on free-flying insects.
The team therefore suggests focusing future research on regions of northern India and Tibet, which are too cold for bats. And now that we have a better idea of what P. dark might sound like, the researchers believe it would be a good idea to install recording devices to try to listen in on these calls, which could lead to the rediscovery of the species.
The study published in PLOS ONE: Reviving the sound of a 150-year-old insect: The bioacoustics of Prophalangopsis obscura (Ensifera: Hagloidea) and presented on the Natural History Museum website: Recreating the song of a 150-year-old insect could help rediscover its species.