Bradshaw J L
Department of Psychology, Monash University, Clayton, Victoria, Australia.
Br J Psychol. 1991 Feb;82 ( Pt 1):39-59. doi: 10.1111/j.2044-8295.1991.tb02381.x.
At the time of the last major review on this subject in the British Journal of Psychology (Walker, 1980) there was, with a few notable exceptions, little evidence of anatomical or behavioural asymmetries in non-human species at all comparable to our own. In the past decade the picture has changed dramatically, and now includes invertebrates from the Cambrian formations of half a billion years ago, many species of birds, rats and mice, antelopes, cats, dogs, whales, and primates. Asymmetries may differ as a function of sex (including hormone status-females of many species including humans appearing more lateralized at a motor level), developmental status and environmental influences. Effects may be manifest anatomically (limb or brain dimensions), or at a sensory, cognitive or motor level (paw preference, turning biases). A recurring observation across species is that the right hemisphere seems to be weakly specialized for spatial and emotional roles, and the left for learning, discriminatory and communicatory functions. Three million years ago our hominid ancestors were more or less fully bipedal, developed the first stone tools and were dextral in manipulating them. However, tool use seems not to have driven the evolution of language, our other strongly lateralized capacity. Evolutionary scenarios for bipedalism, tool use and language are discussed, together with the question of whether human language is continuous, in an evolutionary sense, with earlier primate call systems.
在《英国心理学杂志》（沃克，1980年）上次对该主题进行的重大综述时，除了少数显著的例外情况，几乎没有证据表明非人类物种存在与我们人类相当的解剖学或行为不对称现象。在过去十年中，情况发生了巨大变化，现在包括来自5亿年前寒武纪地层的无脊椎动物、许多鸟类、大鼠和小鼠、羚羊、猫、狗、鲸鱼以及灵长类动物。不对称现象可能因性别（包括激素状态——包括人类在内的许多物种的雌性在运动水平上似乎更具偏侧性）、发育状态和环境影响而有所不同。其影响可能在解剖学上表现出来（肢体或大脑尺寸），或者在感觉、认知或运动水平上表现出来（爪偏好、转向偏差）。跨物种反复观察到的一个现象是，右半球似乎在空间和情感角色方面有较弱的专门化，而左半球则在学习、辨别和交流功能方面有专门化。300万年前，我们的原始人类祖先或多或少已经完全直立行走，发明了第一批石器工具，并且在使用这些工具时惯用右手。然而，工具使用似乎并没有推动语言的进化，语言是我们另一种高度偏侧化的能力。本文讨论了直立行走、工具使用和语言的进化情景，以及从进化意义上讲人类语言是否与早期灵长类动物的叫声系统连续的问题。
