Quantifying the evolutionary dynamics of language
Quantifying the evolutionary dynamics of language
复制标题
DOI：
10.1038/nature06137
复制
发表时间：
2007-10-11
期刊：
影响因子：
64.8
通讯作者：
Nowak, Martin A.
中科院分区：
文献类型：
--
作者：
Lieberman, Erez;Michel, Jean-Baptiste;Nowak, Martin A.
人类语言是基于语法规则（1-4）。文化的进化允许这些规则随着时间的推移而改变（5）。规则相互竞争：随着新规则的崛起，旧规则逐渐消失。为了量化语言演变的动态，我们研究了过去1,200年来英语动词的规则化。虽然在英语的原始日耳曼祖先中存在着一套复杂的生产性变化系统，但现代英语使用牙齿后缀'-ed'来表示过去时态。在这里，我们描述了这一语言规则的出现，在它的例外，我们所知道的不规则动词的进化衰变。我们已经生成了一个动词的数据集，其变化已经演变了一千多年，跟踪177个古英语不规则动词的屈折变化。在这些不规则动词中，有145个在中古英语中仍然是不规则的，98个至今仍然是不规则的。我们研究了正则化的速率如何取决于单词使用的频率。不规则动词的半衰期与其使用频率的平方根成正比：频率低100倍的动词规则化的速度快10倍。我们的研究提供了对规则化过程的定量分析，通过该过程，祖先形式逐渐屈服于新兴的语言规则。
Human language is based on grammatical rules(1-4). Cultural evolution allows these rules to change over time(5). Rules compete with each other: as new rules rise to prominence, old ones die away. To quantify the dynamics of language evolution, we studied the regularization of English verbs over the past 1,200 years. Although an elaborate system of productive conjugations existed in English's proto-Germanic ancestor, Modern English uses the dental suffix, '-ed', to signify past tense(6). Here we describe the emergence of this linguistic rule amidst the evolutionary decay of its exceptions, known to us as irregular verbs. We have generated a data set of verbs whose conjugations have been evolving for more than a millennium, tracking inflectional changes to 177 Old-English irregular verbs. Of these irregular verbs, 145 remained irregular in Middle English and 98 are still irregular today. We study how the rate of regularization depends on the frequency of word usage. The half-life of an irregular verb scales as the square root of its usage frequency: a verb that is 100 times less frequent regularizes 10 times as fast. Our study provides a quantitative analysis of the regularization process by which ancestral forms gradually yield to an emerging linguistic rule.