Casu Marco, Azzena Ilenia, Scarpa Fabio, Locci Chiara, Niffoi Alessio, Delmastro Giovanni Battista, Lo Conte Paolo, Varcasia Antonio, Bovero Stefano, Candiotto Alessandro, Sanna Daria, Cossu Piero
Department of Veterinary Medicine, University of Sassari, 07100 Sassari, Italy.
Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy.
Animals (Basel). 2023 Jan 22;13(3):380. doi: 10.3390/ani13030380.
Biological invasions are a major threat to the conservation of biodiversity, as invasive species affect native biota through competition, predation, pathogen introduction, habitat alteration, and hybridisation. The present study focuses on a southern pike population, (Teleostei: Esocidae), that has been introduced outside the species' native range. Using microsatellite markers, this study's objective was to gather baseline genetic information and assess the presence of hybrids between this species and in the introduced population. The resulting estimates of genetic diversity and effective population size are comparable to those observed in the species' native range. Although different methods yield contrasting and uncertain evidence regarding introgressive hybridization, the presence of late-generation hybrids cannot be completely ruled out. Large numbers of breeders as well as multiple introductions of genetically divergent cohorts and introgressive hybridisation may explain the high genetic diversity of this recently introduced southern pike population. The present study issues a warning that the conservation of southern pike' introgressive hybridisation between northern and southern pike might be underestimated. The genetic information gathered herein may unravel the origin, number of introduction events, and evolutionary trajectory of the introduced population. This information may help us understand the evolution of introgressive hybridisation in the southern pike's native areas.
生物入侵是生物多样性保护面临的主要威胁，因为入侵物种通过竞争、捕食、病原体引入、栖息地改变和杂交等方式影响本地生物群。本研究聚焦于一个引入到该物种原生范围之外的南方狗鱼种群（硬骨鱼纲：狗鱼科）。利用微卫星标记，本研究的目的是收集基线遗传信息，并评估该物种与引入种群中其他物种之间杂种的存在情况。由此得出的遗传多样性和有效种群大小估计值与在该物种原生范围内观察到的结果相当。尽管不同方法对于渐渗杂交产生了相互矛盾且不确定的证据，但不能完全排除晚代杂种的存在。大量繁殖个体以及遗传上不同的群体的多次引入和渐渗杂交可能解释了这个最近引入的南方狗鱼种群的高遗传多样性。本研究发出警告，南方狗鱼渐渗杂交的保护情况可能被低估，北方狗鱼和南方狗鱼之间的渐渗杂交情况可能被低估。本文收集的遗传信息可能揭示引入种群的起源、引入事件的数量和进化轨迹。这些信息可能有助于我们了解南方狗鱼原生区域内渐渗杂交的进化情况。
