CREATURE FEATURE - SPONGES
Sponges are very primitive animals, little more than a mass of cells, without any true tissues or organs. In fact, if a living sponge is forced through a sieve, not only would the cells survive, but they would also regroup to form a new sponge body.
A sponge body is made up of two layers of cells held together by a gel-like substance. Minute needles of silica (glass) within the gel, called spicules, give the sponge body support and offer some protection against predators.
Adult sponges are sessile, or anchored in place, and filter the water for food particles, drawing water in through tiny pores which perforate the sponge body. Sponges are widespread, living on rocks, kelp holdfasts and even spider crabs. Common sponges on the rocky shores of the Moray Firth include the elephant's ear sponge and the breadcrumb sponge.