Department of Earth and Planetary Sciences, University of California, Davis, CA 95616
Proc Natl Acad Sci U S A. 2019 Sep 3;116(36):17619-17623. doi: 10.1073/pnas.1901785116. Epub 2019 Aug 16.
Organic waste, an inevitable byproduct of metabolism, increases in amount as metabolic rates (per capita power) of animals and plants rise. Most of it is recycled within aerobic ecosystems, but some is lost to the system and is sequestered in the crust for millions of years. Here, I identify and resolve a previously overlooked paradox concerning the long-term loss of organic matter. In this efficiency paradox, high-powered species are inefficient in that they release copious waste, but the ecosystems they inhabit lose almost no organic matter. Systems occupied by more efficient low-powered species suffer greater losses because of less efficient recycling. Over Phanerozoic time, ecosystems have become more productive and increasingly efficient at retaining and redistributing organic matter even as opportunistic and highly competitive producers and consumers gained power and became less efficient. These patterns and trends are driven by natural selection at the level of individuals and coherent groups, which favors winners that are more powerful, active, and wasteful. The activities of these competitors collectively create conditions that are increasingly conducive to more efficient recycling and retention of organic matter in the ecosystem.
有机废物是新陈代谢不可避免的副产品,随着动植物代谢率(人均功率)的升高,其数量也会增加。大部分有机废物在好氧生态系统中得到循环利用,但也有一部分会流失到系统之外,并在地壳中封存数百万年。在这里,我发现并解决了一个关于有机物质长期损失的先前被忽视的悖论。在这种效率悖论中,高功率物种效率低下,因为它们会释放大量废物,但它们所栖息的生态系统几乎不会损失有机物质。而效率较低的低功率物种所栖息的系统由于循环效率较低,因此会遭受更大的损失。在整个显生宙时期,即使机会主义和高竞争力的生产者和消费者获得了更多的权力并变得效率更低,生态系统在保留和重新分配有机物质方面的生产力和效率却不断提高。这些模式和趋势是由个体和连贯群体层面的自然选择驱动的,它有利于更强大、更活跃、更浪费的胜利者。这些竞争者的活动共同创造了条件,使生态系统中有机物质的循环利用和保留变得更加高效。