Polyploids with different origins and ancestors form a single sexual polyploid species
Polyploids with different origins and ancestors form a single sexual polyploid species
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DOI：
10.1086/501079
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发表时间：
2006-04-01
影响因子：
2.9
通讯作者：
Hillis, DM
中科院分区：
文献类型：
--
作者：
Holloway, AK;Cannatella, DC;Hillis, DM
多倍化是少数几种能产生瞬间物种形成的机制之一。来自相同的两个二倍体祖先的四倍体谱系的多个起源是常见的，但在这里，我们报告了第一个已知的单一四倍体物种重复起源于至少三个二倍体祖先的实例。广告呼吁在四倍体谱系的灰色树蛙的平行进化，使这些谱系杂交，导致一个单一的性相互作用的多倍体物种，尽管不同的二倍体多倍体的不同起源。在这些青蛙中通过多倍体化形成的物种一直是相当大的争论的来源，但各种已发表的假说都假设多倍体是通过现存二倍体物种的同源多倍体或异源多倍体产生的。我们利用分子标记和广告电话来推断四倍体灰树蛙的起源。以前的假设没有充分考虑到观察到的数据。相反，我们发现四倍体多次起源于现存的二倍体灰树蛙和另外两种显然已经灭绝的树蛙谱系。四倍体谱系然后通过杂交融合，产生单一物种。因此，多倍体物种可能有复杂的起源，特别是在系统中，隔离机制（如广告调用）直接通过杂交和多倍体的影响。
Polyploidization is one of the few mechanisms that can produce instantaneous speciation. Multiple origins of tetraploid lineages from the same two diploid progenitors are common, but here we report the first known instance of a single tetraploid species that originated repeatedly from at least three diploid ancestors. Parallel evolution of advertisement calls in tetraploid lineages of gray tree frogs has allowed these lineages to interbreed, resulting in a single sexually interacting polyploid species despite the separate origins of polyploids from different diploids. Speciation by polyploidization in these frogs has been the source of considerable debate, but the various published hypotheses have assumed that polyploids arose through either autopolyploidy or allopolyploidy of extant diploid species. We utilized molecular markers and advertisement calls to infer the origins of tetraploid gray tree frogs. Previous hypotheses did not sufficiently account for the observed data. Instead, we found that tetraploids originated multiple times from extant diploid gray tree frogs and two other, apparently extinct, lineages of tree frogs. Tetraploid lineages then merged through interbreeding to result in a single species. Thus, polyploid species may have complex origins, especially in systems in which isolating mechanisms (such as advertisement calls) are affected directly through hybridization and polyploidy.