欧亚大陆广布物种的谱系地理研究:现状与发展趋势

Phylogeography of widespread species in Eurasia:Current progress and future prospects

广布物种的地理分布范围涉及欧亚大陆地区,主要分为4种模式:全球分布模式、全北区分布模式、欧亚大陆中高纬度分布模式以及欧亚大陆中低纬度分布模式.通过比较近年来欧亚大陆广布种的谱系地理学的研究结果,总结得出三种谱系地理格局:(ⅰ)'单一组分'格局;(ⅱ)'东-西组分'格局;(ⅲ)'边域组分'格局.本研究分析了欧亚大陆广布种的谱系地理格局形成的成因,主要包括以下三个方面:(ⅰ)物种本身较强的环境耐受力和扩散能力,以及受到人类的贸易、运输、驯养活动的影响;(ⅱ)东-西相异的更新世冰期气候和内陆干旱带来的影响:欧洲在冰期期间大部分区域被冰盖覆盖,物种退到避难所,间冰期物种从避难所向适宜生存的区域扩张,扩张时间大致在末次冰盛期后;亚洲大部分地区的冰期气候相对较为温和,尤其是亚洲东部并没有被大范围冰川覆盖,冰期对这些地区生物的分布格局影响相对较小;此外,由于更新世青藏高原的快速隆升及亚洲夏季风的增强,促进了欧亚大陆内陆干旱带的形成,从而起到长期生态隔离的作用;(ⅲ)边域种化的影响:种群扩散至分布边缘新环境,由于地理或新环境隔离,遗传漂变在小的隔离种群中固定下来,种群间产生遗传分化.通过分析欧亚大陆广布物种在相同地理、地质历史事件下的应对机制的独特性与一致性规律,有助于深入了解广布种在欧亚大陆的地理种群演化及种系发生的形成机制,能够更好地总结、完善整个欧亚大陆生物物种的谱系地理格局的多样性和普遍规律.最后,从大规模核基因组标记的应用和基于物种的生活史特征的预测谱系地理学两个方面对欧亚大陆广布物种的谱系地理学研究提出了展望.

The geographical distribution patterns of the widespread species in Eurasia are classified into four major categories:global distribution,holarctic distribution,mid-high latitude Eurasian distribution,and mid-low latitude Eurasian distribution patterns.By comparing the results of recent phylogeographic studies on the widespread species in Eurasia,we have outlined three phylogeographic patterns:(i)'single-component,'(ii)'east-west component,'and(iii)'peripatric component'patterns.The present study summarizes the factors that potentially influence the phylogeographic patterns of the widespread species in Eurasia.These factors include the following:(i)the relatively high environmental tolerance and dispersal ability of the species as well as the influence of human trade,transportation,and domestication activities;(ii)the east-west diverging Pleistocene glacial climate and the inland arid belt:during glaciation,most regions of Europe were covered with ice sheets;therefore,the species retreated to refuge areas and during the interglacial periods,they recolonized to suitable areas,which facilitated survival after the Last Glacial Maximum.The glacial climates in most parts of Asia were relatively mild,particularly in east Asia,which was less extensively glaciated,as a result of which the glacial period had a relatively low impact on the distribution patterns of species in such areas.In addition,the rapid uplift of the Qinghai-Tibetan Plateau during the Pleistocene and the intensification of the Asian summer monsoon have promoted the formation of the inland arid belt of Eurasia,resulting in long-term ecological isolation.Lastly,(iii)the influence of peripatric speciation:populations disperse to the new marginal environment.Due to geographic or environmental isolation,genetic drift is fixed in small isolated populations,resulting in genetic differentiation among populations.Analyzing the unique and consistent response mechanisms of the widespread species in Eurasia under similar geographical and geological histories would facilitate our understanding of the mechanisms underlying the establishment of geographical populations of the widely distributed species in Eurasia.In addition,this will summarize and identify appropriate diversities and universal principles influencing the phylogeographical patterns of the Eurasian species.Finally,the present study reveals prospective research directions in phylogeography on the widespread species in Eurasia based on large-scale nuclear genome markers and the integration of life history traits into predictive phylogeography.