DNA 研究揭示蛇類如何入侵關島
DNA research reveals how snakes invaded Guam
Updated at: July 27, 2026 at 04:45 AM
外來入侵種在小群體殖民新區域時，通常會面臨「遺傳瓶頸」，這通常會限制牠們的生存。
Invasive species often face a 'genetic bottleneck' when a small group colonizes a new area, which typically limits their survival.
然而，關島的棕樹蛇打破了這條規則，自二次世界大戰後作為貨物偷渡客抵達以來，其密度已達到每平方英里三萬條蛇。
However, the brown tree snake in Guam has defied this rule, reaching densities of up to 30,000 snakes per square mile since arriving as cargo stowaways after World War II.
近期《科學前沿》(Science Advances) 發表的一項研究揭示了這些蛇如何克服嚴重的近親繁殖。
A recent study in Science Advances reveals how these snakes overcame severe inbreeding.
透過使用先進的 DNA 定序技術，研究人員識別出超過一萬九千個「結構變異」(Structural variants)——即遺傳密碼中大規模的改變。
By using advanced DNA sequencing, researchers identified over 19,000 'structural variants'—large-scale changes in their genetic code.
這些變異集中在增強嗅覺與免疫力的基因中，使這些蛇在捕食獵物及抵抗島嶼病原體方面具備顯著優勢。
These variations are concentrated in genes that enhance smell and immunity, giving the snakes a distinct edge in hunting prey and resisting island pathogens.
這項發現解釋了為何這些蛇在初始數量有限的情況下，族群仍能變得如此強韌。
This discovery explains how the population became so resilient despite its limited starting numbers.
這場入侵對當地野生動物造成了毀滅性打擊，導致許多鳥類與蜥蜴滅絕。
The invasion has been devastating for native wildlife, causing the extinction of many birds and lizards.
儘管生態破壞顯而易見，但這項研究為理解「入侵悖論」(Invasion paradox) 提供了突破性進展。
While the ecological damage is clear, this research provides a breakthrough in understanding the 'invasion paradox.'
