Mototi octopus, Lembeh Strait, Indonesia

© Howard Chew/Alamy Stock Phot

Ocean's eight. World Octopus Day

Today, we celebrate a creature with three hearts and the uncanny ability to change colour at will: the octopus. Octopuses are cephalopods, marine animals like squids and cuttlefish that have tentacles. Among their many species is the mototi octopus, pictured here. It was discovered in 1999 around Rapa Island in the South Pacific and is known for the 'fake eyes' or ocelli—vibrant blue and yellow rings—between its eyes and arms. Found in the Indo-Pacific region, including Indonesia, Australia and Okinawa in Japan, mototi octopuses are masters of disguise. They usually have a dull orange-cream-brown colour but when alarmed, they can quickly shift to striking maroon with white stripes along their body and arms. Also known as poison ocellate octopuses, these cephalopods are highly venomous. But you don't need to worry about running into one, because they tend to be shy and solitary, often hiding in crevices, shells or man-made objects like bottles and cans.