Introduction to The Evolution of Human Handedness
Introduction to The Evolution of Human Handedness
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人类惯用手的进化简介
DOI：
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发表时间：
2013
影响因子：
5.2
通讯作者：
L. Marchant
中科院分区：
文献类型：
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作者：
W. McGrew;W. Schiefenhövel;L. Marchant
所有已知的现代智人都喜欢用右手，无论是在运动上、文化上还是在象征意义上;因此，右利手是物种的典型特征。手功能的偏侧性，沿着两足动物和语言，可能是人类普遍而独特的，使得利手成为高度衍生的特征，基于同样专门的神经基质。相反，对于各种非人类物种的脊椎动物（包括其他灵长类动物），偏侧化的程度从某些行为模式的表现偏差到整体的两侧性。生物体可以在个体、科、种群或物种水平上进行侧化。为什么人类如此片面？或者，更准确地说，人类为什么以及如何进化出用手习惯？2011年10月13日至16日，位于德国德尔门霍斯特的汉斯-维森沙夫茨科勒格高等研究院举办了一次研讨会，试图解决这些问题。William C. McGrew（英国剑桥大学）和Wulf Schiefenhövel（德国马克斯普朗克研究所）组织了这次会议，来自8个国家的18名科学家聚集在一起，探讨人类利手的进化;进行了16次演讲和一次公开演讲。大多数与会者为本年鉴卷提供了论文，会后向未出席会议的其他人征求了两篇论文。人类惯用手的现象引起了一系列相关的问题：如果个体的偏侧性足够，为什么群体和物种水平的偏侧性会进化？在人类的过去，用手习惯是什么时候出现的？如何发现？人的一生中，什么时候会出现用手习惯？我们能在多大程度上确定利手的神经基质和遗传基础？其他现存的动物物种是否能提供线索，说明形成这种不寻常的人类适应形式的选择压力？或者，人类的用手习惯只是一种附带现象，不是直接选择的，而是其他选择性力量的副产品，比如那些塑造语言或工具使用的力量？为什么在一个以右撇子为主的世界里，左撇子仍然存在？目前对这些问题的答案从共识到矛盾各不相同：所有人类都有右偏，但程度不同。解释这种变异似乎需要文化和环境变量，但不能排除遗传变量。传统的、无文字的社会可能提供的数据不像工业化社会那样复杂，例如，通过制度化的教育培训。在我们最近的生活关系中，非洲大猿，个体侧化似乎占主导地位，但结果因环境和方法而异。在史前时期，特别是在进化的过去，对功能的偏侧性的测量必然是间接的，正如考古学和古生物学记录所证明的那样。没有一个代理是理想的，都有自己的缺点，但石头（例如，人工制品）和骨骼（例如，cutmarks）可以产生强有力的推论。手动侧化开始于子宫内，但纵向研究表明，感觉和运动的发展并不同步进行。通过禁止或规定，社会上对侧化用手的训练是普遍存在的。在这个过程中，发育可塑性可能会对肌肉骨骼应力产生后天形态不对称。在语言学层面上，用手习惯的语言描述通常倾向于用右手习惯，而往往是以贬低左手习惯为代价的。
All known populations of living Homo sapiens favor the right hand, motorically, culturally, and symbolically; thus right-handedness is species typical. Manual laterality of function, along with bipedality and language, may be both universal and unique to humans, making handedness a highly derived trait, based on an equally specialized neural substrate. In contrast, for various nonhuman species of vertebrates (including other primates), the extent of lateralization varies from bias in the performance of some behavioral patterns to overall ambilaterality. Organisms may be lateralized at the individual, family, population, or species level. Why are humans so one-sided? Or, more precisely, why and how did humans evolve handedness? From October 13–16, 2011, the Hanse-Wissenschaftskolleg Institute for Advanced Study, in Delmenhorst, Germany, hosted a workshop that sought to tackle these questions. William C. McGrew (University of Cambridge, UK) and Wulf Schiefenhövel (Max Plank Institute, Germany) organized the meeting in which 18 scientists from eight countries met to explore the evolution of human handedness; 16 presentations and a public lecture were given. Most participants contributed papers to this Annals volume, and two papers were solicited after the meeting from others who did not attend. The phenomenon of human handedness gives rise to a set of related queries: Why did populationand species-level laterality evolve, if individual laterality sufficed? When in humanity’s past did handedness emerge, and how can this be detected? When in the human life span does handedness emerge? To what extent can we specify the neural substrates and genetic underpinnings of handedness? Do other living species of animals give clues to the selection pressures that shaped the unusual human form of the adaptation? Or, is human handedness just an epiphenomenon, not selected for directly, but instead a by-product of other selective forces, such as those shaping language or tool use? Why does left-handedness persist in a predominately right-handed world? Current answers to these questions vary from consensual to contradictory: all human populations are right biased, but to varying extents. Explaining this variation appears to require both cultural and environmental variables, but genetic variables cannot be ruled out. Traditional, preliterate societies may provide data that are less complicated by, for example, institutionalized educational training, than are industrialized ones. In our nearest living relations, the African great apes, individual lateralization appears to predominate, but results vary across contexts, and by methodology. Measures of laterality of function in prehistory, especially in the deep evolutionary past, are necessarily indirect, as evidenced in both the archaeological and paleontological records. None of the proxies is ideal, and all have their drawbacks, but stones (e.g., artifacts) and bones (e.g., cutmarks) may yield powerful inferences. Manual lateralization begins in utero, but longitudinal study reveals that sensory and motor development does not proceed in lockstep. Societal training for conformity in lateralized hand use, either by proscription or prescription, is ubiquitous. In the process, developmental plasticity may respond to musculoskeletal stresses to produce acquired morphological asymmetries. At the linguistic level, it seems that verbal descriptors of handedness usually favor right-handedness, often at the expense of denigrated left-handedness.