LS Zoologie/Evolutionsbiologie, Universität Regensburg, Regensburg, Germany.
Insect Sci. 2019 Apr;26(2):333-340. doi: 10.1111/1744-7917.12530. Epub 2017 Nov 8.
Most disturbed habitats in the tropics and subtropics harbor numerous species of invasive ants, and occasionally the same species has been introduced repeatedly from multiple geographical sources. We examined how experimental crossbreeding between sexuals from different populations affects the fitness of queens of the tramp ant Cardiocondyla itsukii, which is widely distributed in Asia and the Pacific Islands. Eggs laid by queens that mated with nestmate males had a higher hatching rate than eggs laid by queens mated to males from neighboring (Hawaii × Kauai) or distant introduced populations (Hawaii/Kauai × Okinawa). Furthermore, inbreeding queens had a longer lifespan and produced a less female-biased offspring sex ratio than queens from allopatric mating. This suggests that the genetic divergence between different source populations may already be so large that in case of multiple invasions eventual crossbreeding might negatively affect the fitness of tramp ants.
在热带和亚热带地区，大多数受干扰的栖息地都栖息着许多种入侵蚂蚁，而且偶尔同一物种会从多个地理来源被反复引入。我们研究了来自不同种群的有性个体之间的杂交实验如何影响广泛分布在亚洲和太平洋岛屿的流浪蚁 Cardiocondyla itsukii 的蚁后的适合度。与与同巢雄蚁交配的蚁后产下的卵相比，与来自邻近（夏威夷×考艾岛）或遥远引入的种群（夏威夷/考艾岛×冲绳）的雄蚁交配的蚁后的卵孵化率更高。此外，与来自地理隔离交配的蚁后相比，近亲繁殖的蚁后寿命更长，产生的雌蚁与雄蚁性别比例偏差更小。这表明不同来源种群之间的遗传分化可能已经很大，在多次入侵的情况下，最终的杂交可能会对流浪蚁的适合度产生负面影响。
