The narwhal, often referred to as the “unicorn of the sea” in a nod to its trademark tusk, has long remained an enigma. Scientists have observed few interactions of narwhals in their natural habitat, creating speculation about the purpose of the species’ distinctive spiraling tusk. Now scientists say they have the first recorded video evidence of narwhals using tusks not only to strike and manipulate fish during feeding but also engage in what appears to be playful behavior: https://cnn.it/3FdNc