文獻來源：C Kerdelhué et al.. 2009. Quaternary history and contemporary patterns in a currently expanding species. BMC Evolutionary Biology 9: 220 doi:10.1186/1471-2148-9-220背景
第四紀的氣候振盪對物種的演化造成巨大的影響。在高緯度地區，族群必須在避難所區域度過嚴寒的冰河期，然後週期性地在間冰期拓殖回高緯度地帶。這種歷史通常會導致遺傳多樣性的損失；反之，未經歷過冰河時期的族群，可能會比其祖先具有較高的遺傳多樣性。這些特色強烈影響到現今的遺傳多樣性分佈狀況，甚至影響到這些物種如何因應當前的全球變遷。作者針對一種廣分佈的松舟蛾複合群(Thaumetopoea pityocampa/T. wilkinsoni complex, Notodontidae)進行粒線體遺傳多樣性的研究，該種是地中海盆地與南歐地區的森林性害蟲。此物種對近期氣候變遷的反應為快速的自然擴張其分佈區域，其中或許也包括偶然的人為遷移。本研究的目標是探討第四紀冰河期氣候振盪是否影響該物種的分佈範圍，以及判斷晚近拓殖地區的族群是否能鑑別岀近代遷移過程的遺傳足跡。
結果
作者鑑別岀三個具有地理結構的主要支系。在大部份的歐洲地區，其遺傳岐異度的樣式符合典型經過顯著冰河週期的物種。除了避難所以外，歐洲的各個族群的特色為只具有一種單倍基因型(haplotype)與基因多樣性極低，此特色被預期發生在氣候條件變好時受到物種快速地重新拓殖的地區。相反地，其他在地中海盆地周圍的次支系發生在受限的部分且有強烈的空間結構，如同受冰河影響有限的區域，在各個族群中保留其高度的遺傳多樣性，且大多數的單倍基因型是該地特有的。這種格局在地中海的遙遠離島（克里特島、塞普勒斯、科西嘉島）上格外顯著，亦具有特有的單倍基因型。近期引入的典型是會在地理分佈距離遙遠的族群間出現非常近似的單倍基因型，但是由於缺乏整體的遺傳結構、故在歐洲大部份的地區難以偵測。
結論
在冰川作用不明顯的地區，晚近的蛾類引入/擴張可由是否存在強烈的空間遺傳結構來偵測。反之，經歷第四紀冰河期強烈氣候振盪的區域，其天然族群則缺乏遺傳結構，而晚近的族群擴張樣式則尚無法偵測。
Abstract
Background Quaternary climatic oscillations had dramatic effects on species evolution. In northern latitudes, populations had to survive the coldest periods in refugial areas and recurrently colonized northern regions during interglacials. Such a history usually results in a loss of genetic diversity. Populations that did not experience glaciations, in contrast, probably maintained most of their ancestral genetic diversity. These characteristics dramatically affected the present-day distribution of genetic diversity and may influence the ability of species to cope with the current global changes. We conducted a range-wide study of mitochondrial genetic diversity in the pine processionary moth (Thaumetopoea pityocampa/T. wilkinsoni complex, Notodontidae), a forest pest occurring around the Mediterranean Basin and in southern Europe. This species is responding to the current climate change by rapid natural range expansion and can also be accidentally transported by humans. Our aim was to assess if Quaternary climatic oscillations had a different effect across the species' range and to determine if genetic footprints of contemporary processes can be identified in areas of recent introduction.
Results We identified three main clades that were spatially structured. In most of Europe, the genetic diversity pattern was typical for species that experienced marked glaciation cycles. Except in refugia, European populations were characterized by the occurrence of one main haplotype and by a strong reduction in genetic diversity, which is expected in regions that were rapidly re-colonized when climatic conditions improved. In contrast, all other sub-clades around the Mediterranean Basin occurred in limited parts of the range and were strongly structured in space, as is expected in regions in which the impact of glaciations was limited. In such places, genetic diversity was retained in most populations, and almost all haplotypes were endemic. This pattern was extreme on remote Mediterranean islands (Crete, Cyprus, Corsica) where highly differentiated, endemic haplotypes were found. Recent introductions were typified by the existence of closely-related haplotypes in geographically distant populations, which is difficult to detect in most of Europe because of a lack of overall genetic structure.
Conclusion In regions that were not prone to marked glaciations, recent moth introductions/expansions could be detected due to the existence of a strong spatial genetic structure. In contrast, in regions that experienced the most intense Quaternary climatic oscillations, the natural populations are not genetically structured, and contemporary patterns of population expansion remain undetected.
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