Filter feeding mechanism of sponge moves water through body by intaking low and releasing high.
“A sponge takes in water at its base, filtering the food from it and expelling it through holes higher up.” (Courtesy of the Biomimicry Guild)
Image: Kimmo Hagman / Shutterstock / Some rights reserved
Capture, Absorb, or Filter Organisms
Many living systems must secure organisms for food. But just as one living system must capture its prey to survive, its prey must escape to survive. This results in capture and avoidance strategies that include trickery, speed, poisons, constructed traps, and more. For example, a carnivorous plant called the pitcher plant has leaves formed into a tube that collect water. Long, slippery hairs within the tube face downward. When insects enter the tube seeking nectar, they lose their footing and slide inside, unable to climb out and escape being eaten and digested by the plant.
Sponges
Phylum Porifera (“pore-bearing”): Sponges
Sponges may seem simple, but there’s more to them than meets the eye. True, they don’t have nerves, muscles, or organs. But they do have unique, specialized cells that help them survive. Collar cells have long tails or flagella that line the inner sponge cavity and funnel water through the body. Sponges are filter feeders, taking in large amounts of water and trapping tiny particles to eat. They also have small spiky spicules made of silica or calcium carbonate that help them keep their structure. There are at least 5,000 known species of sponges living in aquatic systems, with 98% of them in the ocean.
