Unchanged for hundreds of centuries, and with no close relatives on the evolutionary tree, the sponge remains a very simple and primitive form of animal. Sponges have a remarkable ability to withstand enormous loss of body material, suddenly growing many times faster than normal to regain the original size. The average lifespan for individual specimens was estimated to be 50 years or more.
The simplest type of sponge is shaped somewhat like a vase, with feeding cells on the inner wall. Water is drawn through minute pores in the outer wall and expelled through the large main aperture. The present is maintained by the feeding cells, each with a very small whip that’s waved always back and forth. Because of the huge volume of water contained inside the chamber in proportion to the inner wall surface of cells, higher forms of sponges have adapted by folding out the interior walls to improve the feeding area.
On low tide areas of the beach could be found lots of the apartment in crusting sponges. These appear in a wide array of colors and have no definite shape of their own, instead taking on the kind of the rock beneath.
Some kinds of sponge are capable of releasing a poisonous substance to prevent the encroachment of acquaintances, and several of these toxins are used in research laboratories for the preparation of human medicines.