摘要
世界上已知有十多种动物的最大寿命(Amax)可超过100年,淡水珍珠贝(Margaritifera margaritifera)即是其中的一种。这种动物寿命较长者可达到100～200年,寿命的长短与其生活地的环境条件及所处纬度有关。淡水珍珠贝南方种群与北极地区种群相比,其寿命差异可以达3～7倍。一些南方种群的最大寿命为28～40年,而在北极地区则可达到114～190年。用进化和生态学的观点来看,北极地区珍珠贝长寿的原因可能是因为这些地区性种群已适应了当地恶劣、多变的气候及水文条件,寒冷气候条件下较低的代谢率及生长过程中较低的能量消耗均对长寿产生了积极的影响。为使损坏的贝壳或机体组织得以修复或自愈,这类物种通常能很快地将其代谢率水平增加至130倍。通过对这类物种进行生理学的研究,相信在理解长寿和延迟衰老的机理方面能有极大的收获。
Only about a dozen species of animals are known to achieve maximum ages (Amax) i.e. exceeding 100 yr., including the freshwater pearlshell (Margaritifera margaritifera). This species has a life-span of between 100-200 years depending on latitude and environmental conditions. The difference in Amax is 3-7 times when southern populations, with Amax of 28-40 years, are compared to northern Arctic populations, with Amax of 114-190 years. Evolutionary and ecological explanations for longevity in the Arctic pearlshell include adaptations to the severe, unstable climatic and hydrological conditions in rivers. Extreme longevity seems to be related not only to the low metabolic rate in the cold climate, but the species can reduce energy expenditure for growth, and can rapidly increase metabolic rate up to 130x the normal level, to regenerate damaged shell or tissue. The physiology of this species may provide valuable clues to understanding the mechanisms that sustain longevity and retard senescence.Ambio, Vol. 29, No. 2, pp. 102-105, 2000
