These sea creatures, the Pyura chilensis, start life as tiny tadpoles as larvae. They also have everything little tadpoles have - including a brain. They need this above all in order to find a suitable place for their further development. It should be a rock in the sea on which they can settle and which they will never leave again and in the vicinity of which there is enough plankton for their nutrition. Once they have found their future home, they begin to reject their brains and - after all, they are hungry - to finish eating. The adult hermaphroditic organisms no longer need this body part for food intake and reproduction.
The meat of the piure has a spicy, very intense taste and is often used in Chilean cuisine. Arroz con piure picado (rice with chopped piure) is available in many seafood restaurants. The inhabitants of the cliffs of Chile often at risk of death, equipped with wetsuits and diving goggles, gather piure in the dangerous surf of the Pacific Ocean. Piure can be eaten raw or cooked and is high in iodine, vanadium and iron. The following video is from 2011, here a group of German tourists finds Piure beach and cut it open to see what the inside looks like ...