This animal looks something like a hot water bottle clinging to a rock. It feeds by straining water to retrieve plant and animal micro-organisms as well as organic debris. It has two siphons that do this: one in the upper part, through which it takes in water, and the other on the side, to breathe it out. Each animal has a ring of bristles that it uses to close its orifice whenever it is disturbed, and to prevent the intrusion of inedible particles.
When it detects danger, the sea squirt contracts, expelling the water from its cavity, and curls up into a small, tough mass.
Sea squirts reproduce in November. An egg fertilized by a spermatozoon produces a larva that looks like a tadpole. Each one has an axis: its cord, the equivalent of a spinal column. After living an unfettered life, the larva attaches to the ground and metamorphoses. At that point, its tail and cord recede. The temporary presence of that axis gives the sea squirt a special place in the classification of animals.
The artist on stage