Leonard W R, Robertson M L
Department of Anthropology, University of Florida, Gainesville 32611, USA.
Am J Phys Anthropol. 1997 Feb;102(2):265-81. doi: 10.1002/(SICI)1096-8644(199702)102:2<265::AID-AJPA8>3.0.CO;2-X.
There is currently great interest in developing ecological models for investigating human evolution. Yet little attention has been given to energetics, one of the cornerstones of modern ecosystem ecology. This paper examines the ecological correlates of variation in metabolic requirements among extant primate species, and uses this information to draw inferences about the changes in energy demands over the course of human evolution. Data on body size, resting metabolism, and activity budgets for selected anthropoid species and human hunter-gatherers are used to estimate total energy expenditure (TEE). Analyses indicate that relative energy expenditure levels and day ranges are positively correlated with diet quality; that is, more active species tend to consume more energy-rich diets. Human foragers fall at the positive extremes for modern primates in having high expenditure levels, large ranges, and very high quality diets. During hominid evolution, it appears that TEE increased substantially with the emergence of Homo erectus. This increase is partly attributable to larger body size as well as likely increases in day range and activity level. Assuming similar activity budgets for all early hominid species, estimated TEE for H. erectus is 40-45% greater than for the australopithecines. If, however, it is assumed that the evolution of early Homo was also associated with a shift to a more "human-like" foraging strategy, estimated expenditure levels for H. erectus are 80-85% greater than in the australopithecines. Changing patterns of resource distribution associated with the expansion of African savannas between 2.5 and 1.5 mya may been the impetus for a shift in foraging behavior among early members of the genus Homo. Such ecological changes likely would have made animal foods a more attractive resource. Moreover, greater use of animal foods and the resulting higher quality diet would have been important for supporting the larger day ranges and greater energy requirements that appear to have been associated with the evolution of a human-like hunting and gathering strategy.
目前，人们对开发用于研究人类进化的生态模型有着浓厚的兴趣。然而，作为现代生态系统生态学基石之一的能量学却很少受到关注。本文研究了现存灵长类物种代谢需求变化的生态关联，并利用这些信息推断人类进化过程中能量需求的变化。选取的类人猿物种和人类狩猎采集者的体型、静息代谢和活动预算数据用于估算总能量消耗（TEE）。分析表明，相对能量消耗水平和日间活动范围与饮食质量呈正相关；也就是说，活动较多的物种往往食用能量更丰富的饮食。人类觅食者在现代灵长类动物中处于积极极端，具有高消耗水平、大范围活动和非常高质量的饮食。在人类进化过程中，随着直立人的出现，总能量消耗似乎大幅增加。这种增加部分归因于体型增大以及日间活动范围和活动水平可能的增加。假设所有早期人类物种的活动预算相似，直立人的估计总能量消耗比南方古猿高出40 - 45%。然而，如果假设早期人类的进化也与向更“类人”的觅食策略转变有关，直立人的估计消耗水平比南方古猿高出80 - 85%。250万至150万年前非洲稀树草原扩张导致的资源分布变化模式可能是人类属早期成员觅食行为转变的动力。这种生态变化可能使动物食物成为更具吸引力的资源。此外，更多地食用动物食物以及由此产生的更高质量饮食对于支持更大的日间活动范围和更高的能量需求可能很重要，而这些似乎与类人狩猎和采集策略的进化有关。
