Worldwide diversity of hair curliness: a new method of assessment
Worldwide diversity of hair curliness: a new method of assessment
复制标题
DOI：
10.1111/j.1365-4632.2007.03453.x
复制
发表时间：
2007-10-01
影响因子：
3.6
通讯作者：
de la Mettrie, Roland
中科院分区：
文献类型：
--
作者：
Loussouarn, Genevieve;Garcel, Anne-Lise;de la Mettrie, Roland
多年来，化妆品科学家一直试图测量人类头发的物理特征，例如其形状和颜色，因为这些可以使用化妆品进行人工修改。关于头发的形状，以前的人类学研究强调了它在人类种族群体内部和之间的变异性。许多研究已经大致区分了三个种族人类亚群：非洲人，亚洲人和高加索人。这种宽泛的分类无法解释人类生物多样性的巨大复杂性，这是多种、过去或最近的混合起源造成的。对头发形状的口头描述从经典到更复杂，如直，波浪，卷曲，卷曲，扭结，羊毛状，螺旋状等，虽然这些描述唤起了全球的外观，但它们仍然令人困惑，因为它们的定义和限制不清楚。评估，因此需要更准确地定义这样的口头attributes.Objective工作报告这里试图解决以下问题：（i）定义头发类型根据特定的形状标准，通过客观和简单的测量;以及（ii）在不涉及人类种族的情况下定义这种头发类型。方法测量与头发卷曲相关的四个参数在来自22个不同国家的2449名受试者的头发上进行了头发的卷曲度（曲线直径、卷曲指数）或扭结度（波浪数、扭曲数）的测量。主成分分析和等级上升分类被用来确定同质组的头发，并确定组成员的分配的关键变量。最后，一个分割树的准备，以建立简单的规则，预测组成员的新subjects.Results和结论这项研究表明，它是可能的各种头发类型的分类发现世界各地的8个主要群体。该方法涉及头发形状的客观描述符，并且比依赖于卷曲，波浪和扭结等类别的传统方法更可靠。适用于世界范围内的人类多样性，它避免了参考假定的，不明确的种族起源的主题。简单地说，I型直发就是这样，它是来自高加索人还是亚洲人并没有争议。这里定义的头发类型也更充分地反映了世界各地头发形状多样性的巨大变化，并可能有助于追溯人类亚群之间过去的混合起源。
Background For many years, cosmetic scientists have attempted to measure the physical features of human hair, such as its shape and colour, as these can be artificially modified using cosmetic products. With regard to hair shape, previous anthropologic studies have emphasized its variability within and between human ethnic groups. Many studies have broadly distinguished three ethnic human subgroups: African, Asian, and Caucasian. Such a broad classification cannot account for the great complexity of human biological diversity, resulting from multiple, past or recent mixed origins. The verbal description of hair shape ranges from the classic to the more sophisticated, with terms such as straight, wavy, curly, frizzy, kinky, woolly, helical, etc. Although these descriptions evoke a global appearance, they remain confusing as their definitions and limits are unclear. Assessments are therefore required to more accurately define such verbal attributes.Objective The work reported here attempts to address the following issues: (i) to define hair types according to specific shape criteria through objective and simple measurements; and (ii) to define such hair types without referring to human ethnicity.Methods Measurements of four parameters related to hair curliness (curve diameter, curl index) or kinking of the hair (numbers of waves, numbers of twists) were performed on hair from 2449 subjects from 22 different countries. Principal components analysis and hierarchical ascendant classification were used to identify homogeneous groups of hair and to determine key variables for the assignment of group membership. Finally, a segmentation tree was prepared in order to establish simple rules for predicting group membership of new subjects.Results and conclusions This study has shown that it is possible to classify the various hair types found worldwide into eight main groups. The approach involves objective descriptors of hair shape, and is more reliable than traditional methods relying on categories such as curly, wavy, and kinky. Applied to worldwide human diversity, it avoids reference to the putative, unclear ethnic origin of subjects. Briefly, a straight hair type I is just that, and whether it originates from a Caucasian or an Asian subject is not at issue. The hair types defined here also more adequately reflect the large variation of hair shape diversity around the world, and may possibly help to trace past mixed origins amongst human subgroups.