The birds and the bees, the flowers and the trees, and the moon up above -- nope, we’re not here to sing about a thing called love (sorry Jewel Akens fans), we’re actually here to talk about a thing called sound. While we’re always ready to rave about the latest innovations in the audio and communications tech world, we also know how some of the most complex uses of acoustics come directly from nature.
From insects and primates to flowers and trees, there are some seriously impressive uses of sound in nature. We thought it would be fun to take a step away from technology for a moment and highlight the impressive innovations that come directly from nature. Check out our top 6 list of the most innovative uses of sound in nature:
1: The buzzing connection between bees and flowers 🐝
Recently, Tel Aviv University researcher Lilach Hadany found an interesting connection between bees and flowers. Hadany’s research aimed to better understand if plants, like animals, could sense sounds. The research did indeed conclude that in at least one case, plants can hear.
The team looked at evening primroses and found that within minutes of sensing vibrations from a pollinator’s wings, the plants would temporarily increase the concentration of sugar in their nectar. The flower of the plant was working effectively as an “ear”, picking up the frequencies of the bees’ wings, while also tuning out irrelevant noises like wind. The ability for plants to hear and respond to a bee’s presence, according to Hadany, could be an essential element to help the species survive.
2: Spiders and their sonic sensor networks 🕷
Spider webs have intrigued researchers -- as it turns out, the silky artwork serves a more complex role than simply acting as a trap for prey. Spiders’ webs have unusual acoustic properties, which allow the spider to utilize them for a variety of critical survival acts.
Research from the Royal Society Interface shows that spiders acoustically tune the strings of their webs, and can decode their vibrations to detect the positions of its ensnared prey. It also allows them to sense the structural integrity of the web, the presence of potential mates or predators, and even atmospheric conditions such as wind.
Further, a study by Nature Materials showed that spider silk is also capable of blocking the transmission of certain frequencies of “phonons”, quasiparticles of sound that travel along the filaments.
3: Moths, the cheeky percussionists 🦋
Moths aren’t really known for their vocal skills, but some species of moths actually produce sound. Certain moth species generate genuine warning signals letting their adversaries know they’re not a tasty treat, but others will mimic this defense mechanism to deceive hunters.
Tiger moths, for example, use tiny blisters of cuticle called tymbal organs on the sides of their thorax. The moths create a clicking sound, similar to squeezing and releasing an aluminum can. Delicate cycnia moths also use this technique to advertise their toxic taste, created from eating plants imbued with toxins as a caterpillar. Bats quickly recognize these signals and avoid these moths. Other moths, who are perfectly edible, have learned to utilise this cheeky percussionist technique to avoid becoming a snack.
4: Philippine tarsiers ultrasonic communication 🙉
The Philippine tarsier may be a tiny, tree-top dwelling primate, but it has the unique ability to communicate purely in ultrasonic frequencies -- the only primate able to do so. Some primates can emit and respond to calls with ultrasonic components, but none, other than the tarsier, can communicate purely in ultrasonic.
The tarsier’s dominant call frequency falls around 70kHz, the highest recorded for any terrestrial mammal. They can also hear up to 90kHz, which is well beyond the 20kHz limit of human hearing. As such, the tarsiers have a practically private communication channel in which to warn one another of encroaching danger, without alerting predators. They can also eavesdrop on insects in the area to help them locate a tasty snack.
5. High pitch hummingbirds 🔊
Hummingbirds are tiny, fascinating, and feisty. When it comes to showing off for a potential mate however, they can pull off some interesting aerial displays, showing off their brightly coloured throats, and throwing themselves into a deep dive from meters high. As they do their aerial dances, they generate a high-pitched, distinctive sound.
Previously, scientists thought this noise was made with their vocal chords. However, Christopher Clark, a biologist at the University of California, Riverside, was reviewing and old journal theorizing the sound came from the bird’s rapid descents. Upon testing the theory with hummingbirds who did and did not have tail feathers, Clark found that those with tail feathers indeed create high-pitched noises, as the fast-moving air vibrates their plumes.
6. Thirsty talking trees 🌳
Droughts are a serious issue for every type of wildlife, including trees, which actually produce sound to cry for help. A team of French scientists captured the ultrasonic noise made by bubbles forming inside the water-stressed trees. Trees, however, have been documented making other ultrasonic tunes before, but until this report, they were unable to detect which sounds could be worrisome.
With this knowledge, research is continuing to better understand when trees are parched and need emergency watering to save them. Read more here to find how about how trees ingest water and about the acoustic events of trees.
Bonus: Lyrebirds, masters of mimicry: Just for fun, to round out the list, here’s a clip of the Lyrebird, the ultimate master of mimicry, imitating chainsaws, car alarms, and a camera shutter: