Eric Baccega / Polar bear (Ursus maritimus) feeding on a Narwhal (Monodon monoceros), Arctic Bay, Baffin Island, Nunavut, Canada, June.

Jeff Rotman / Orangespine unicornfish (Naso lituratus) profile portrait, Red Sea, Egypt.

Flip Nicklin / Narwhal (Monodon monoceros) male surfacing, Canadian Northwest Territories

Flip Nicklin / Narwhal (Monodon monoceros) surfacing, Baffin Island, Nunavut, Canada

Flip Nicklin / Narwhal (Monodon monoceros) males sparring over carcass of dead female, Baffin Island, Canada

Flip Nicklin / Narwhal (Monodon monoceros) group in ice break, Baffin Island, Nunavut, Canada

Flip Nicklin / Narwhal (Monodon monoceros) group of males, Baffin Island, Nunavut, Canada

Flip Nicklin / Narwhal (Monodon monoceros) males, Lancaster Sound, Baffin Island, Canada

Espen Bergersen / The Einhyrningur mountain. The name means "The Unicorn", and is derived from the shape of the mountain. Iceland, October 2017. Digitally stitched panorama.

Alex Mustard / A portrait of a tiny Unicorn goby (Cerogobius petrophilus). Gubal Island, Egypt. Red Sea.

Gary Bell/ Oceanwide / Unicornfish (Naso vlamingii), Papua New Guinea

David Fleetham / Orangespine unicornfish (Naso lituratus), female amongst Bigscale soldierfish (Myripristis berndti) school, Hawaii.