Every group of Mexican tetra fish speaks with a different accent. Scientists studied both the blind cave-dwelling populations and those that live in rivers. They all communicate using a series of clicks, but the sighted and non-sighted fish use those “words” for different purposes. Fish from each cave also changed their use of language in different ways, from their pitch to “speech” pace.
The scientists played sounds from other groups to fish from the river or a specific cave. Sure enough, miscommunications occurred. The noise cave fish make while foraging for food is similar to the one river fish make when they’re fighting. When researchers played the cave fish sound for the river fish, they responded as if an aggressive fish was nearby. Whereas cave fish came towards the noise, assuming there was a good food source.
The scientists used a little aquatic sound studio to capture the varying fish accents. The studio might just be the coolest part of the research. Whether in their natural habitats or in the lab, each group of fish had a little microphone (called a hydrophone once it’s in the water) to record their sounds. And also a speaker for the scientists to play noises from other populations. Like a home recording studio, the tank in the lab set up featured acoustic sound panels.
We learned about the study from New Scientist. The study isn’t peer-reviewed and published in a scientific journal yet. It does, however, follow up on a previous study the prestigious peer-reviewed journal Nature published.
Despite the fact that some populations have eyes while others don’t, they are all the same species. An estimated 20,000 years ago, some of the fish started living in caves. Over time, they lost not only their eyesight but their eyes entirely. They are also paler, translucent enough that you can see their organs through their scales. The ocean contains over 200 known species of blind cave fish worldwide. And the video below contains a whole lot of cool information about them.
Scientists study these populations to understand animal communication and how languages evolve over time. There are other groups working on sperm whale language and even communication amongst mushrooms.
Melissa is Nerdist’s science & technology staff writer. She also moderates “science of” panels at conventions and co-hosts Star Warsologies, a podcast about science and Star Wars. Follow her on Twitter @melissatruth.