Sharks, traditionally known as the silent and predatory type, may actually have the ability to make sounds intentionally. This discovery was made by evolutionary biologist Carolin Nieder and her colleagues as they recorded clicking sounds in sharks, marking the first time such deliberate sound production has been documented in these sea creatures. While fishes have long been known to produce various sounds, sharks and rays, built with cartilage, have been slower to be recognized for their ability to sound off. The discovery of clicking sounds in cownose rays in 1971 paved the way for the recent findings in sharks.
The clicking sounds in sharks were discovered accidentally by Nieder while she was handling a small shark species called a rig in a tank at the University of Auckland’s Leigh Marine Lab in New Zealand. Upon further investigation, it was found that the sound may be a result of the shark clacking its teeth together. The rows of flattened teeth in the shark’s mouth are specialized for cracking crustaceans shells, which could explain the purpose behind the sound production. Through her research with 10 sharks, Nieder recorded multiple instances of clicking, suggesting that the sound may be voluntary and not a response to stress.
The discovery of sharks making deliberate sounds opens up a new realm of understanding about their communication abilities. The sounds were recorded during various activities, indicating that the clicking is not dependent on the shark’s movements or behaviors. It is hypothesized that the sharks produce these sounds through forceful snapping, but further research is needed to confirm this theory. Additionally, the limitations of shark hearing, which is below 1,000 Hz compared to human hearing which can reach up to 20,000 Hz, provide insights into their sensory world and how they perceive their environment.
Sharks are known for their remarkable senses, such as detecting changes in electric fields in water, making them sensitive to their surroundings. While they may not have the most acute hearing compared to other aquatic animals, their ability to produce sounds intentionally adds another layer to their communication repertoire. The findings hint at the complexity of shark behavior and the importance of further research to unravel the mysteries of these fascinating creatures. The accidental discovery of clicking sounds in sharks sheds light on the hidden abilities and communication methods of these apex predators in the marine ecosystem.
