Nature’s Living Rock

At first glance Pyura chilensis looks like nothing more than a regular beach rock. But when cut open, their bright red contents will make you think you’ve discovered an alien specimen. Despite appearances, Pyura chilensis is a sea creature that lives on the rocky coasts of Chile and Peru and are fished commercially. The locals eat them raw or cooked with rice because they’re tasty and considered a delicacy.

The outer rock-like appearance of Pyura chilensis is called its tunicin which consists of a strong band of molecules that helps it attach itself to a hard surface. The tunicin is lined with an epidermis and a muscular band and it is inside of these layers that lies the main part of the animal. It has two siphons and eats by inhaling water through one and filtering out the edible micro algae before exhaling the water back out the other. 

Pyura chilensis is also a hermaphroditic, with the gonads of both a male and a female, that can release eggs and sperm simultaneously that meet as a fertile cloud in the surrounding water. When the sperm-egg collisions are successful, they produce tiny tadpole-like offspring. Nature has yet again produced a truly bizarre life form with the ultimate in camouflage.

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