Hydrozoans are mostly colonial organisms. A colony is composed of individual members that are physically connected and adapted to share resources such as food. Most hydrozoan colonies are 2 to 6 inches high. The colonies usually contain two types of polyp. The feeding polyp captures food and feeds the colony. The reproductive polyp is specialized for the process of reproduction.
Not all hydrozoans form colonies. Members of the hydrozoan orders Siphonophora and Chondrophora produce floating colonies (ex. the Portuguese man-of-war), where the colony is suspended from a large gas sac that acts as a float. These floating colonies contain several types of specialized polyps. Feeding polyps function in digestion, and fishing polyps capture prey. Other parts of the colony are modified medusae that contain ovaries or testes and function in reproduction.
0 Comments
|
|