This video says about itself:
Listen to a narwhal’s resting heartbeat | Science News
7 December 2017
Narwhals have a resting heart rate of about 60 beats per minute. Now researchers have observed narwhals’ heart rate dropping precipitously low when diving to escape from humans. As melting sea ice opens up the Arctic to more human activity, the mammals, known as “unicorns of the sea” for their single tusk, may be more exposed to the potentially harmful escape response, scientists say.
Narwhals react to certain dangers in a really strange way. ‘Unicorns of the sea’ fleeing humans show the physiological signs of also being frozen in fear. By Mariah Quintanilla, 2:41pm, December 7, 2017.
This video says about itself:
Science News – Whales & Dolphins Have “Human-Like” Societies
19 October 2017
AI eavesdrops on dolphins and discovers six unknown click types. Computer program picked out the noises from underwater recordings of 52 million echolocation signals. By Maria Temming, 2:00pm, December 7, 2017.
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