Search results
Results from the WOW.Com Content Network
Planktivorous fish (8, some damselfishes and triggerfishes) transfer energy from zooplankton up to reef predators like jacks (9), [101] which provide top-down control of reefs [102] and are important targets for shoreline recreational fisherfolk. [103] Grazers (10, chubs) help keep coral reefs from being overgrown by macroalgae. [104]
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. [1] Most coral reefs are built from stony corals, whose polyps cluster in groups. Coral belongs to the class Anthozoa in the animal phylum Cnidaria, which includes sea anemones and ...
At least one microscopic animal group, the parasitic cnidarian Myxozoa, is unicellular in its adult form, and includes marine species. Other adult marine microanimals are multicellular. Microscopic adult arthropods are more commonly found inland in freshwater, but there are marine species as well.
Reefs can also grow on other surfaces, which has made it possible to create artificial reefs. Coral reefs also support a huge community of life, including the corals themselves, their symbiotic zooxanthellae, tropical fish and many other organisms. Much attention in marine biology is focused on coral reefs and the El Niño weather
Mangrove area has declined worldwide by more than one-third since 1950, [65] and 60% of the world's coral reefs are now immediately or directly threatened. [66] [67] Human development, aquaculture, and industrialization often lead to the destruction, replacement, or degradation of coastal habitats. [64]
The classification of corals has been discussed for millennia, owing to having similarities to both plants and animals. Aristotle's pupil Theophrastus described the red coral, korallion, in his book on stones, implying it was a mineral, but he described it as a deep-sea plant in his Enquiries on Plants, where he also mentions large stony plants that reveal bright flowers when under water in ...
Coral reefs are some of the most biodiverse habitats on earth, supporting large numbers of species of corals, fish, molluscs, worms, arthropods, starfish, sea urchins, other invertebrates and algae. Because of the photosynthetic requirements of the corals, they are found in shallow waters, and many of these fringe land masses. [ 24 ]
The sponges form reefs (called sponge reefs) off the coast of British Columbia, southeast Alaska and Washington state, [15] which are studied in the Sponge Reef Project. In the case of Sarostegia oculata, this species almost always hosts symbiotic zoanthids, which cause the hexactinellid sponge to imitate the appearance and structure of coral ...