Scientists Reconstruct 165-Million-Year-Old Jurassic Insect Songs

Scientists Reconstruct 165-Million-Year-Old Jurassic Insect Songs — And One Was Already Ultrasonic

Using lasers, computer models and AI, researchers reconstructed the calls of 165-million-year-old cricket and katydid relatives from fossilized wings found in China. One species produced ultrasonic frequencies above 20 kHz — predating bats by 110 million years and overturning the assumption that bat predation drove insects into the ultrasonic realm.

Key Takeaways

Using lasers, computer models and AI, researchers reconstructed the calls of 165-million-year-old cricket and katydid relatives from fossilized wings found in China.
One species produced ultrasonic frequencies above 20 kHz — predating bats by 110 million years and overturning the assumption that bat predation drove insects into the ultrasonic realm.

AI synthesis4 sources12

Researchers have reconstructed the mating calls of insects that lived 165 million years ago during the Jurassic period, revealing a surprisingly complex ancient soundscape — and evidence that ultrasonic communication existed in insects long before bats evolved.

The study, published in the Proceedings of the National Academy of Sciences (PNAS) by Dr. Jun-Jie Gu of Sichuan Agricultural University and colleagues, analyzed 20 fossilized wing fragments from nine species of ensiferan insects (relatives of modern crickets and katydids) unearthed from the Jiulongshan Formation in Inner Mongolia, China.

The fossils, dated to the Middle Jurassic, preserved the delicate stridulatory structures — the file and plectrum — that these insects used to 'sing' by rubbing one wing against the other. These sclerotized cuticle structures fossilize well, preserving a physical fingerprint of the acoustic signals the insects once produced.

To reconstruct the ancient songs, the team combined phylogenetic analysis comparing the fossils to nearly 100 living insect species, laser vibrometry measurements of modern insect wings, computer simulations of how the fossilized wings would have vibrated, and machine-learning models trained to predict call patterns from wing shape.

Most of the nine species produced low, pure-tone calls around 5 kilohertz, similar to some living crickets. But one species — Sigmaboilus peregrinus — produced calls above 20 kHz, in the ultrasonic range beyond human hearing.

This finding upends a long-standing assumption in evolutionary biology. Bats, which use echolocation to hunt insects, are widely credited with driving the evolution of ultrasonic communication in insects — a way to 'whisper' at frequencies bats couldn't hear. But bats didn't appear until roughly 55 million years after these Jurassic insects were already producing ultrasonic calls.

"We reject the hypothesis that bats were the sole driver of ultrasound evolution in katydids," the authors wrote. "Instead, it is likely that early mammals and non-mammalian ancestors were also listening in to the songs of ensiferans, driving early diversification of acoustic signaling strategies."

The researchers also suggest that competition for acoustic space among multiple calling species in crowded Jurassic forests may have pushed some insects toward higher frequencies — a form of acoustic niche partitioning similar to what ecologists observe in modern tropical forests.

The paper, titled "Reconstruction of an extinct soundscape reveals ultrasonic communication in the Jurassic," was published on August 25, 2026 in PNAS (doi: 10.1073/pnas.2615107123).