Diving into the waters of Antarctica, these scientists did not expect such a discovery: Weddell seals produce ultrasound. what purpose ? It remains a mystery.
« Calls fromCreate an almost unbelievable soundscape from another world under the ice »Paul Cziko, one of the authors of the appreciation On their singing. Like other pinnipeds, these Semi-aquatic sailor with wing-shaped legs, Waddell’s voices that are audible to humans. Until now, scientists had no doubt that they also produce . « It really feels like you’re in the middle of a space war in Smiling Star Wars and all »Excites the researcher.
Between 2017 and 2018, a team of universities from Oregon (United States) and New Brunswick (Canada) dive into the frozen watersRecording these vowels. Unexpectedly, their Sounds audible to humans have collected. But in listening, scientists realized: ultrasounds were seized on tape. ” Eventually we realized that the seals were using [ces appels ultrasonores] regularly Says co-writer Lisa Munger.
He counted to nine. newUp to 50 kHz, although some hormones were over 200 kHz! For comparison, the human ear sounds between 20 and 20,000 – or 20 kHz. These ultrasonic calls now represent 17% of the known seal call repertoire. But an unknown relic: what are they for?
Nine vowels, two hypotheses
« You never know what you are going to getAnd ears in the ocean, especially Antarctica »Says Paul Cziko. This scientist speculates two possible causes of the ultrasound call. On one hand, they can be used for ” Stand out from low frequency noise like switching to a separate channel for communication “. On the other hand, they can allow Say that one Organic is used to navigate when visibility is limited. During’ For example, Antarctica, which seals Weddell in the dark for several months.
To uncover this mystery, researchers are planning large recordings. ” How do seals use these sounds? Lisa asks Munger, We need to record more locations to see correlations with behavior ».