Organism responses to rapid change: What aquaria tell us about nature

Living corals are routinely collected and shipped to destinations thousands of mires from their point of origin. The fact that corals can survive the rigors of collecting, transport, and acclimation to totally artificial envi ronments was considered impossible not long ago, but hobbyists and some res earchers have persevered and have developed aquarium systems and techniques capable of maintaining corals in apparently healthy condition for many yea rs. In particular, new lighting equipment, advances in the control of water chemistry, and new technology for simulating water movement have all contr ibuted to the ability to keep corals alive indefinitely in captivity, Despi te the completely artificial conditions of most aquariums, coral extension rates and calcification rates in some aquarium systems are close to those r eported for natural reefs, although anomalies have been observed such as de creased skeletal density and unusual changes in colony morphology, Nonethel ess, aquariums present real opportunities to culture corals for a variety o f bioassay, medicinal, and conservation purposes. As model reef communities ("microcosms"), these systems allow us to test hypotheses concerning the e ffects of rapidly changing environmental conditions.