The co-evolution of human hands and tool using behaviour

当你和人们谈论人类与其他动物的不同之处时，他们会很快识别出人类的手。事实上，他们很可能会认为“相对的拇指”是人类独有的特征。虽然可以争辩说这不是严格意义上的事实，但可以肯定的是，没有其他动物拥有人类对手的精确控制程度。我们认为单个手指的精细动作是理所当然的，这些动作让我们可以弹钢琴或系鞋带，而这些活动是非人类不可能完成的。我们物种的进化史很可能与我们双手的进化史密切相关，因此这是一个重要的科学研究领域。我们目前知道很多关于我们的手的形状是如何与近亲物种的手的形状发生变化的，但实际上我们对这些形状的变化与手的功能如何相关的了解很少。我们与黑猩猩和现代人共同祖先的分歧包括用后肢行走，石器的创造，我们智力的增长，以及广泛的社会群体生活。人类手的功能发生了变化，失去了它的运动角色，允许它操纵和感知世界的专门化，并扩大了它在交流中的作用，这成为了一个令人信服的叙事。特别是，我们手的进化与我们对日益复杂的工具的采用密切相关的观点似乎非常有道理。因此，本研究项目的目的是探索人类手的功能能力的变化，并利用这些信息来评估手的进化历史及其与工具使用和制造的关系。为了实现这一目标，我们需要收集关于人类如何使用手的各个部分的信息。这需要以一种受控的方式完成，这样我们就可以对不同动作的机械要求进行客观比较，我们可以将这些机械要求与非血液学记录中的特定人工制品联系起来。因此，我们建议在执行这样一系列任务时收集人类的运动和力信息。我们将使用一系列为虚拟现实和电影特效开发的令人兴奋的新技术，在这些技术中，可以使用特殊仪器的手套和将反光标记连接到手指上，自动记录手部和手指的动作。此外，仅仅记录这些信息不足以完全理解像手这样复杂的机制。我们还将使用来自医学成像和解剖的信息来构建这些手和手臂运动的3D计算机模拟。然后，我们将使用各种复杂的机械工程技术来评估单个骨骼和肌肉在手中的功能。我们还需要评估人类的手功能是如何随着时间的推移而变化的，这意味着我们需要调查灵长类化石及其在世亲属的手。为了做到这一点，我们将为这些从化石骨骼重建的灭绝物种创建等效的计算机模拟。计算机模型将使我们能够预测这些物种的能力，我们将能够直接评估随着时间的推移，我们最近的祖先的手的运动、觅食和工具使用能力的变化。

When you talk to people about what makes humans different from other animals, one of the features that they will rapidly identify is the human hand. Indeed they are very likely to identify the 'opposable thumb' as a uniquely human characteristic. Whilst it can be argued that this is not strictly true, it is certainly the case that there are no other animals that have anything like the degree of precise control of their hands that humans have. We take for granted the fine movements of individual fingers that allow us to play the piano or tie our shoelaces, and these are activities that are impossible for non-humans to achieve. It is likely that the evolutionary history of our species is very closely linked to the evolutionary history of our hands and this is therefore an important area for scientific study. We currently know a great deal about how the shape of our hands has changed from those of closely related species but we actually know very little about how these shape changes are linked to how the hand functions. The story of our divergence from the common ancestor of chimpanzees and modern humans includes walking on our hindlimbs, the creation of stone tools, the increase in our intelligence, and living in extended social groups. The change in function of the human hand by losing its locomotor role and allowing its specialisation for manipulating and sensing the world, and extending its role in communication becomes a compelling narrative. In particular the idea that the evolution of our hands is closely linked to our adoption of increasingly sophisticated tools seems extremely plausible.Thus the aim of this research project is to explore the changes in functional capabilities of the human hand and to use this information to evaluate the evolutionary history of the hand and its relationship to tool use and manufacture. To achieve this goal we need to collect information about how the individual parts of the hand are used in humans. This needs to be done in a controlled fashion so that we can make objective comparisons of the mechanical requirements of different actions that we can link to specific artifacts in the achaeological record. We therefore propose to collect movement and force information from humans whilst performing such a range of tasks. We will use a range of exciting new technologies developed for virtual reality and movie special effects where hand and finger movements can be recorded automatically using specially instrumented gloves and by attaching reflective markers to the fingers. In addition simply recording this information is insufficient to fully understand a mechanism as complex as a hand. We will also construct 3D computer simulations of these hand and arm movements using information from medical imaging and dissections. We will then use a variety of sophisticated mechanical engineering techniques to evaluate how the individual bones and muscles function within the hand. We also need to evaluate how human hand function has changed over time and this means that we need to investigate the hands of fossil primates as well as their living relatives. To do this we will create equivalent computer simulations for these extinct species reconstructed from the fossil bones. The computer models will allow us to predict the capabilities of these species and we will be able to directly evaluate the changes in locomotor, foraging and tool use capabilities of the hands of our closest ancestors over time.