阿拉伯芥是第一個完成基因體定序的開花植物，其基因體資訊提供植物學研究的重要依據；在解析阿拉伯芥屬物種的親緣關係以及種化機制等重要的演化議題時，阿拉伯芥近緣的野生物種自然成了不可或缺的關鍵；跟阿拉伯芥近緣的物種包括A. halleri及A. lyrata，其中A. halleri ssp. gemmifera (葉芽阿拉伯芥)主要分布於中國東北、日本以及台灣，與近緣的A. halleri ssp. halleri其分布於歐洲隔著天山及大陸的障蔽，而A. lyrata ssp. kamchatica (玉山阿拉伯芥)主要分布於東北亞及台灣，與分布於北美五大湖的A. lyrata ssp. lyrata被北極圈所分隔，這樣的分布模式暗示異域種化的可能。
藉由多基因分析比較祖先物種與現生物種遺傳歧異度的相關可提供訊息探討種化時期的族群遺傳結構，本研究針對A. halleri ssp. gemmifera、A. halleri ssp. halleri及A. lyrata ssp. kamchatica、A. lyrata ssp. lyrata四個物種，兩對互為亞種的姊妹群，以阿拉伯芥為外群進行研究，在四個物種完成98個同源基因的分子序列，利用套裝軟體MCMCcoal來估算祖先物種的遺傳變異，亦估算現生物種的核苷酸歧異度，觀察到許多物種配對中祖先物種遺傳多型性大於現生物種DNA歧異度，顯示異域種化模型並無法完全解釋阿拉伯芥屬物種的種化模式，在某些物種配對間鄰域種化模式應比異域種化更為可能；在基因樹與物種樹的比較，98個基因片段的親緣模式只有28個是與已知物種樹一致的，有23個基因其樹狀圖支持{[(kamchatica, gemmifera), halleri], lyrata}, thaliana的型式，藉由kamchatica位置的變化以及估算各物種配對間的平均同義置換率，推測在A. halleri ssp. gemmifera與A. lyrata ssp. kamchatica間具有近代的單方向基因交流。

During the postgenomics era, the information about genomic sequence and gene functions provides a new foundation for evolutionary biology and ecology. As the first whole-genome sequenced plant, Arabidopsis thaliana and its wild relatives have played a critical role in understanding the evolution of genomics and speciation. Both A. halleri and A. lyrata are closely related to the model species A. thaliana. A. halleri ssp. gemmifera occurs in northeastern China, Japan and Taiwan; while its sister A. halleri ssp. halleri is mainly distributed in Europe. Geographical barriers, such as Tienshan Mountain Range, isolate these intraspecific sisters. Likewise, A. lyrata ssp. kamchatica and ssp. lyrata occur in East Asia and North America, respectively. Such distribution patterns seem to be consistent with allopartic speciation.
The comparison between ancestral and extant polymorphism by multilocus can be informative about the population genetics of speciation. In this study, we collected and analyzed DNA sequences of 98 genes from four wild relatives of A. thaliana, A. halleri ssp. gemmifera, A. halleri ssp. halleri, A. lyrata ssp. kamchatica and A. lyrata ssp. lyrata. The ancestral states of these four species were compared to each other in terms of level of genetic variation. However, the ancestral species at the time of speciation were substantially more polymorphic than the extant geographical populations. The observations are not fully compatible with speciation by strict allopatry. At some species pairs parapatric speciation seems more reasonable in speciation of Arabidopsis. The 98 gene sequences are also used for the congruence test between gene genealogy and species phylogeny. Only 28 genes support the species phylogeny, but there are 23 genes supports another major genealogy, {[(kamchatica, gemmifera), halleri], lyrata}, thaliana. Based on the phylogenetic position change of A. lyrata ssp. kamchatica and Ks value for each species pair suggested the recent directional gene flow between A. halleri ssp. gemmifera and A. lyrata ssp. kamchatica.

黃增泉(1993) 植物分類學：台灣維管束植物科誌，國立編譯館，台北。
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