Frizzi Filippo, Bartalesi Viola, Santini Giacomo
Department of Biology, University of Florence, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Florence, Italy.
Department of Biology, University of Florence, Via Madonna del Piano 6, 50019 Sesto Fiorentino, Florence, Italy.
J Therm Biol. 2017 Apr;65:76-81. doi: 10.1016/j.jtherbio.2017.02.007. Epub 2017 Feb 16.
The invasive garden ant, Lasius neglectus, is a dominant species due to its capacity to form large supercolonies. This species was assumed to possess a wide thermal niche since it is able to adapt to cold climates, which is a factor that boosted its rapid expansion from south to many central-northern European Countries. However, the effect of variations in environmental temperatures on its competitive ability against other species has still not been investigated. In this paper, we analyzed the change in survival ability of Lasius neglectus during encounters with two Mediterranean dominant ants (Crematogaster scutellaris and Tapinoma nigerrimum) at four different temperatures (15, 20, 25 and 30°C). Firstly, control tests were performed to provide the baseline survival ability of the three species at different temperatures. Secondly, competition tests were carried out at the same temperatures. Lasius neglectus survival was negatively affected by high temperature (30°C) in control tests, and this impairment was much more pronounced in competition tests. On the contrary, the two opponent species were only marginally affected by temperatures in control tests. Crematogaster scutellaris was a better competitor than L. neglectus, particularly at high temperatures. Tapinoma nigerrimum was a weaker competitor and was always outcompeted by L. neglectus, particularly at low temperatures. This result could suggest that L. neglectus is at a disadvantage during interspecific encounters when temperatures are high and that the predicted future increase in environmental temperatures may potentially enhance this handicap.
入侵性花园蚁，即忽视拉斯蚁（Lasius neglectus），因其能够形成大型超级蚁群而成为优势物种。由于这种蚂蚁能够适应寒冷气候，所以被认为具有广泛的热生态位，这也是它从南方迅速扩张到许多欧洲中北部国家的一个因素。然而，环境温度变化对其与其他物种竞争能力的影响尚未得到研究。在本文中，我们分析了忽视拉斯蚁在与两种地中海优势蚂蚁（盾胸切叶蚁Crematogaster scutellaris和黑褐小家蚁Tapinoma nigerrimum）相遇时，在四个不同温度（15、20、25和30°C）下生存能力的变化。首先，进行对照试验以提供这三个物种在不同温度下的基线生存能力。其次，在相同温度下进行竞争试验。在对照试验中，高温（30°C）对忽视拉斯蚁的生存产生了负面影响，而在竞争试验中这种损害更为明显。相反，在对照试验中，这两种对手物种仅受到温度的轻微影响。盾胸切叶蚁比忽视拉斯蚁更具竞争力，尤其是在高温下。黑褐小家蚁竞争力较弱，总是被忽视拉斯蚁击败，尤其是在低温下。这一结果可能表明，当温度较高时，忽视拉斯蚁在种间相遇中处于劣势，而预计未来环境温度的升高可能会加剧这种不利状况。
