Katydids put on a lively musical performance when they call to attract females or defend their territory, creating sound by rubbing two hardened areas of their wings together–one like a zipper and the other like a file ridge ridge ridge ridge ridge.
Scientists have observed that females prefer male singers who can harmonize perfectly when singing (known as stridulation).
Stridulation
Stridulation, the generation of sound through friction between surfaces, is common among orthoptera, including katydids. Their hard exoskeleton allows them to develop stridulation organs virtually everywhere on their body surface – for instance, on wings as an attractant mechanism.
Male Ensifera males produce calls and protest sounds using a typical stridulatory apparatus located, as with most Ensifera species, on the basis of their terminals. On the left tegmen is located the pars strides with its row of teeth rubbing against a plectrum situated near the terminal margin of lower wings when calling songs; when singing songs, this file makes contact with it at both upstrokes and downstrokes of music calling songs, this contact occurs every time upstroke or downstroke!
Common Meadow Katydid (Conocephalus fasciatus) can often be heard during summer choruses. Their song features ticks followed by buzzes; sometimes, individual katydids will synchronize their ticking and buzzing to produce an exciting, unique throbbing sound.
Katydids produce short, harsh, and high-pitched sounds called protest noises to attract potential mates or as a warning signal against predators, defend territory, or announce the mating season. These sounds may also serve to attract or warn off predators.
Katydids make their distinctive sound by banging their bodies together, which results in their characteristic screeching alarm call, often heard when males attempt to attract females for mating purposes.
People may be shocked to learn that katydids have ears on their legs rather than heads. Katydids with legs-based ears can better detect soundwaves, making it easier to see potential mates or predators more quickly and move swiftly towards them or away from danger.
Singing
Northern Hemisphere summer evenings become an audible cacophony of katydid songs throughout much of summer. From dusk into nightfall, males of Pterophylla camellifolia’s common accurate katydid species form choruses with one another that drown out almost all other sounds – their songs being an array of raspy tones between 3 kHz to 20kHz with pitches that range between them.
Katydids differ from crickets and grasshoppers by making sounds by rubbing two parts of their wings together instead of striking an object or substrate, which is called stridulation. Their wings have been specially modified for sound production with bumps and grooves on each underside for good show; sharp edges called scrapers on one branch rub against comb-like files on opposing wings to produce vibrations that produce the song of katydids.
Scraper and file have a unique design to amplify their sound output, with sharp edges of two wings producing a constant stream of sound; forewings bow out to form an amplification chamber to enhance calls; this unique structure makes the katydid song one of nature’s loudest calls.
When male katydids hear female katydids, they abruptly stop singing their song and switch to an individual courtship call that attracts explicitly her. He may also vibrate his body in what’s known as emulation – giving the female an audible packet of sperm through vibrations that travel down her body directly to her reproductive organs.
Males use songs as a form of communication over long distances. A dominant singer can often be heard more clearly than his rivals’ calls, and this helps maintain territorial and mating boundaries.
Researchers have studied the wings of modern-day katydids, and Montealegre-Zapata collaborated with Daniel Robert to use these readings as the input into an audio model of an ancient Jurassic katydid. Together, they reconstructed its song, which can be found here; specifically, it would emit a tone at 6.4kHz for 16 milliseconds before dying off again.
Detection of Predators
Katydids produce various sounds to attract mates, defend their territories, and even fight rival males. Additionally, these insects are known for being excellent predator detection mechanisms – researchers have shown how the sounds produced by their wings can help pinpoint any nearby threats.
At its core, katydids use wing-rubbing (known as stridulation) to produce vibrations, which then increase within their bodies, making high-pitched noise that both their auditory system and pinnae can detect.
Scientists have discovered that katydid vocalizations serve as an early warning system, alerting potential prey of approaching predators as well as warning other insects of impending danger. When threatened, some katydids will cease their stridulation when encountering either predators or competitors, emitting a short, low-pitched call known as a defensive flutter before quickly stopping stridulation and returning to wing-rubbing mode.
Katydids produce high-pitched sounds known as tremulations to advertise themselves to females or rivals. Tribulations are made by rhythmically shaking of their abdomen and transmitted through thin air layers in their exoskeleton to create vibrations in plants, which are picked up by the auditory system and pinnae of animals nearby.
While most studies of katydid sound have focused on their acoustic signals, scientists have recently begun studying their vibrational signals as well. A recent investigation in a Neotropical forest found that while most species produced calls through vibrations for communication purposes only, some also created defensive noises when threatened by predators; it marked the first time such sounds were made when there was danger around.
Potentially, katydids could use similar acoustic signals to detect bat presence; however, the researchers were unable to confirm this finding. Instead, they noted that the calling rates of katydids decreased when present; this may be because the frequency of echolocation calls from bats is higher than katydid stridulations or regulations sounds.
Communication
Katydids produce sounds far beyond the human hearing range. Like crickets, katydids make sounds by rubbing their wings together – an act known as stridulation – while creating vibrations within extraordinary veins on their wings that contain rows of small teeth-like structures that make noise when they rub against one another.
Katydids communicate with one another via vibrations produced when male katydids brush their hind leg against their wings, creating a rhythmic sound similar to their calling song. Katydids use these vibrations to locate other members of their species as well as deter predators. Pulses produced this way allows katydids to identify each other quickly while also differentiating between calling males and females of the same species.
Male katydids create intricate songs during mating season to lure females and mark their territory, as well as communicate important information about fitness and desirability for reproduction. Females use these sounds to discriminate among the various species to prevent unwitting mating with individuals of the wrong species.
Scientists have recently made an exciting discovery: Katydids communicate more efficiently than previously imagined. A study of forest soundscape revealed that other nearby katydids amplify sound signals sent from one individual katydid to the extent of at least 30dB within 10 meters due to geometric spreading reducing active range and, therefore, signal amplitude detectable by receivers.
An identical effect was witnessed when an isolated katydid was placed inside an enclosure with walls. While its vibrational signals increased when there was wind blowing through its chamber, when left alone, they became absent entirely. The research suggests that katydids have evolved to use their environments effectively by sensing both vibrational and acoustic signals from their backgrounds.
