[Article] 一種毒蝶中隱藏的遺傳分化與斑紋多樣性
摘要 [原文網址]
Despite rampant colour pattern diversity in South America, Heliconius erato exhibits a ‘postman’ wing pattern throughout most of Central America. We examined genetic variation across the range of H. erato, including dense sampling in Central America, and discovered a deep genetic break, centred on the mountain range that runs through Costa Rica. This break is characterized by a novel mitochondrial lineage, which is nearly fixed in northern Central America, that branches basal to all previously described mitochondrial diversity in the species. Strong genetic differentiation also appears in Z-linked and autosomal markers, and it is further associated with a distinct, but subtle, shift in wing pattern phenotype. Comparison of clines in wing phenotype, mtDNA and nuclear markers indicate they are all centred on the mountains dividing Costa Rica, but that cline width differs among data sets. Phylogeographical analyses, accounting for this new diversity, rewrite our understanding of mimicry evolution in this system. For instance, these results suggest that H. erato originated west of the Andes, perhaps in Central America, and as many as 1 million years before its co-mimic, H. melpomene. Overall our data indicate that neutral genetic markers and colour pattern loci are congruent and converge on the same hypothesis—H. erato originated in northwest South America or Central America with a ‘postman’ phenotype and then radiated into the wealth of colour patterns present today.
毒蝶的故事太複雜，之後再來整理，先總結一下這篇的結論。（本篇請搭配中南美洲地圖服用）
這篇也是利用族群遺傳的方法討論Heliconius erato的分化，用了好幾個分子標記（詳情請自行參閱本文）與十分密集的取樣，即使如此仍發現H. erato在哥斯大黎加的山區兩側的族群有遺傳分化。而這個種根據本文的分析則顯示可能起源於哥斯大黎加（中美洲起源，與之前的假說是從南美洲的安地斯山起源不同），而起源的時間則比其co-mimics Heliconius melpomene早了一百萬年。如果這個假說成立，則最早的斑紋是一個叫做postman樣式的斑紋，從中美洲起源後 擴散至南美洲。
ps. 種起源與斑紋的起源可能不同啊......
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