Sales Lilian Patrícia, Ribeiro Bruno R, Hayward Matt Warrington, Paglia Adriano, Passamani Marcelo, Loyola Rafael
Conservation Biogeography Lab, Department of Ecology, Universidade Federal de Goiás, Goiânia, Brazil.
Programa de Pós-graduação em Ecologia e Evolução, Universidade Federal de Goiás, Goiânia, Brazil.
J Anim Ecol. 2017 Sep;86(5):1214-1223. doi: 10.1111/1365-2656.12721. Epub 2017 Jul 26.
Niche conservatism, i.e. the retention of a species' fundamental niche through evolutionary time, is cornerstone for biological invasion assessments. The fact that species tend to maintain their original climate niche allows predictive maps of invasion risk to anticipate potential invadable areas. Unravelling the mechanisms driving niche shifts can shed light on the management of invasive species. Here, we assessed niche shifts in one of the world's worst invasive species: the wild boar Sus scrofa. We also predicted potential invadable areas based on an ensemble of three ecological niche modelling methods, and evaluated the performance of models calibrated with native vs. pooled (native plus invaded) species records. By disentangling the drivers of change on the exotic wild boar population's niches, we found strong evidence for niche conservatism during biological invasion. Ecological niche models calibrated with both native and pooled range records predicted convergent areas. Also, observed niche shifts are mostly explained by niche unfilling, i.e. there are unoccupied areas in the exotic range where climate is analogous to the native range. Niche unfilling is expected as result of recent colonization and ongoing dispersal, and was potentially stronger for the Neotropics, where a recent wave of introductions for pig-farming and game-hunting has led to high wild boar population growth rates. The invasive potential of wild boar in the Neotropics is probably higher than in other regions, which has profound management implications if we are to prevent their invasion into species-rich areas, such as Amazonia, coupled with expansion of African swine fever and possibly great economic losses. Although the originally Eurasian-wide distribution suggests a pre-adaptation to a wide array of climates, the wild boar world-wide invasion does not exhibit evidence of niche evolution. The invasive potential of the wild boar therefore probably lies on the reproductive, dietary and morphological characteristics of this species, coupled with behavioural thermoregulation.
生态位保守性，即物种在进化过程中对其基本生态位的保留，是生物入侵评估的基石。物种倾向于维持其原始气候生态位这一事实，使得入侵风险预测图能够预判潜在的可入侵区域。阐明驱动生态位转移的机制有助于深入了解入侵物种的管理。在此，我们评估了世界上最具危害性的入侵物种之一：野猪（Sus scrofa）的生态位转移情况。我们还基于三种生态位建模方法的集合预测了潜在的可入侵区域，并评估了用本地物种记录与汇总（本地加入侵地）物种记录校准的模型的性能。通过剖析外来野猪种群生态位变化的驱动因素，我们发现了生物入侵过程中生态位保守性的有力证据。用本地和汇总分布记录校准的生态位模型预测出了趋同区域。此外，观察到的生态位转移大多可以用生态位未填满来解释，即在外来分布范围内存在气候与原生范围相似但未被占据的区域。由于近期的定殖和持续扩散，生态位未填满是可以预期的，在新热带地区可能更为明显，最近一波为养猪和狩猎引进野猪的浪潮导致该地区野猪种群增长率很高。野猪在新热带地区的入侵潜力可能高于其他地区，如果我们要防止它们入侵物种丰富的地区，如亚马逊地区，同时应对非洲猪瘟的扩散并可能造成巨大经济损失，这将具有深远的管理意义。尽管野猪最初在欧亚大陆广泛分布表明其对多种气候具有预适应性，但全球范围内的入侵并未显示出生态位进化的证据。因此，野猪的入侵潜力可能在于该物种的繁殖、饮食和形态特征，以及行为体温调节。
