ENVS 111 Lecture 12: Envs 111 - 12th class
Document Summary
Economic value: tourism valued at . 6 billion, fishery valued at . 7 billion, ecosystem services estimated at . 5 billion. Symbiosis a close biological or ecological relationship between two species in a mutualism, individuals of both species benefit from the symbiosis. Zooxanthellae coral symbiosis zooxanthellae: provided with a sheltered (safe) place in which to live, excrement from corals fuels metabolic processes. Corals: consume organic matter that zooks produce through photosynthesis healthy bleached. Small branching corals will die within 10 days. Abnormally high temperatures result in thermal stress, and many corals respond by expelling the symbiotic algae (zooxanthellae) that live in the corals" tissues. Since the zooxanthellae are responsible for most of the corals" color, corals that have expelled their algal symbionts appear to be bleached. Not all coral species are equally sensitive to temperature stress. Within species, there is variation in how individuals respond to stress.
