Humans are evolutionarily adapted to caloric restriction resulting from ecologically dictated dietary deprivation imposed during the Plio-Pleistocene period
Humans are evolutionarily adapted to caloric restriction resulting from ecologically dictated dietary deprivation imposed during the Plio-Pleistocene period
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DOI：
10.1016/j.mehy.2005.11.013
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发表时间：
2006-01-01
影响因子：
4.7
通讯作者：
Amen-Ra, N
中科院分区：
文献类型：
--
作者：
Amen-Ra, N
由于生态上的饮食限制，人类在进化上适应了慢性营养不良。干旱加剧、气温降低和气候振荡加剧，改变了古人类在更新世-更新世时期赖以生存的植被的数量和质量。原始人对气候诱导的卡路里减少的生理反应与生物体对实验施加的卡路里限制的反应相同：通过降低速度和/或改变它们代谢燃料的方式。这种代谢变化主要是由下丘脑介导的，这里假设人类下丘脑受到相当大的选择性压力，促进了能量保守的低代谢状态。此外，人类物种最显著的表型特征--长寿命、低繁殖潜力、长发育和高大脑/体重比在接受热量限制的生物体中实现。这些表型/生理特征--这里称为四分复合体--可以受代谢率的调节，而代谢率又受下丘脑的调节。在200万至150万年前，气候发生了明显的变化，在这一交界点上，一个原始人血统(类人猿)灭绝了。类人猿的特征是具有健壮的颅面部等外部适应能力。形态和明显的釉质沉积，表明以坚韧、低质量的植物食物为生。相反，人的血统通过内部方式对其边际饮食体系做出反应，以代谢抑制为中心。这里假设，这种适应性代谢改变，是对生态施加的热量限制的反应，产生了人类明确的形态特征，并使人类物种能够进化成功。这种思路的含义之一是，现代人可能对过量摄入能量的有害影响特别敏感，随之而来的是，特别容易受到卡路里限制的改善效果的影响。(C)2005爱思唯尔有限公司。保留所有权利。
Humans are evolutionarily adapted to chronic undernutrition as a consequence of ecologically dictated dietary restriction. Increased aridity, cooler temperatures and increased climatic oscillation effected an alteration of the quantity and quality of vegetation upon which hominids depended for food during the Plio-Pleistocene period. Hominids responded physiologically to climate-induced caloric curtailment in the same way organisms respond to experimentally imposed caloric restriction: by reducing the rate and/or altering the manner in which they metabolized fuel. Such metabolic alterations are mediated principally by the hypothalamus and it is herein hypothesized that the human hypothalamus was subjected to substantial selective pressure, promoting an energetically conservative hypometabolic state. Moreover, the most salient phenotypic characteristics typifying the human species - long lifespan, low reproductive potential, lengthy development and high brain/bodyweight ratio are effectuated in organisms undergoing caloric restriction. These phenotypic/physiological characteristics - herein termed the quadripartite complex - can be modulated by metabolic rate, which is, in turn, modulated by the hypothalamus. An appreciable alteration in climate occurred between 2.0 and 1.5 million years ago, a juncture at which one hominid Lineage (Paranthropus) went extinct. Paranthropus was characterized by such external adaptations as robust cranio-facial. morphology and pronounced enamel deposition, indicative of subsistence on tough, low-quality vegetal foods. Conversely, the Homo lineage responded to its marginal dietary repertoire through internal means, centering on metabolic suppression. It is herein hypothesized that this adaptive metabolic alteration, enacted in response to ecologically imposed caloric restriction, produced the defining morphologic attributes of Homo and enabled the evolutionary success of the human species. Among the implications of this line of thinking is that modern humans may be particularly sensitive to the deleterious effects of excess energy intake and, concomitantly, particularly amenable to the ameliorative effects of caloric restriction. (c) 2005 Elsevier Ltd. All rights reserved.