Nie Yufan, Wang Zikang, Yu Simin, Zhang Luyao, Liu Rui, Liu Yuping, Zhu Wentao, Zhou Zhiqiang, Diao Jinling
Department of Applied Chemistry, China Agricultural University, Yuanmingyuan West Road 2, Beijing 100193, China.
School of Food and Biological Engineering, Shaanxi University of Science and Technology, Xi'an 710021, China.
Sci Total Environ. 2023 Jun 25;879:163078. doi: 10.1016/j.scitotenv.2023.163078. Epub 2023 Mar 25.
Life-history theory suggests that organisms must distribute a limited share of their energetic resources among competing life-history trait demands. Therefore, the trade-off strategies individuals develop for particular life-history traits in a given environment may profoundly impact their environmental adaptability. In this study, lizards (Eremias. argus) were exposed to single and combined atrazine (4.0 mg·kg and 20.0 mg·kg) and different temperatures (25 °C and 30 °C) for 8 weeks during the breeding season. The effects of atrazine and warming on the adaptability of lizards were explored by examining changes in trade-offs via several key life history traits (i.e., reproduction, self-maintenance, energy reserves, and locomotion). The results show that after atrazine exposure at 25 °C, both female and male lizards tended to allocate energy to self-maintenance by reducing energy allocation to reproductive process. The lower energy reserves of males are considered a "risky" life-history strategy and the observed higher mortality may be related to atrazine-induced oxidative damage. The retention of energy reserves by females not only ensured their current survival but also facilitated survival and reproduction in subsequent stages, which can be regarded as a "conservative" strategy. However, under high temperature and/or combined atrazine exposure, the "risky" strategy of males caused them to consume more energy reserves to invest in self-maintenance, which ensured their immediate survival, and profited from more rapid degradation of atrazine. In contrast, the "conservative" strategy of females could not meet their higher reproductive and self-maintenance demands under high temperatures, and the elevated reproductive oxidative and metabolic costs led to individual mortality. Gender differences in life-history trade-off strategies can directly lead to "winners" and "losers" from environmental stress within a species.
生活史理论表明，生物体必须在相互竞争的生活史特征需求之间分配有限的能量资源份额。因此，个体在特定环境中为特定生活史特征所形成的权衡策略可能会深刻影响其环境适应性。在本研究中，在繁殖季节，将丽斑麻蜥暴露于单一和混合的莠去津（4.0毫克·千克和20.0毫克·千克）以及不同温度（25℃和30℃）下8周。通过研究几个关键生活史特征（即繁殖、自我维持、能量储备和运动能力）的权衡变化，探讨了莠去津和升温对蜥蜴适应性的影响。结果表明，在25℃下暴露于莠去津后，雌性和雄性蜥蜴都倾向于通过减少对生殖过程的能量分配，将能量分配给自我维持。雄性较低的能量储备被认为是一种“冒险”的生活史策略，观察到的较高死亡率可能与莠去津诱导的氧化损伤有关。雌性保留能量储备不仅确保了它们当前的生存，还促进了后续阶段的生存和繁殖，这可以被视为一种“保守”策略。然而，在高温和/或混合莠去津暴露下，雄性的“冒险”策略使它们消耗更多的能量储备来投入自我维持，这确保了它们的即时生存，并从莠去津更快的降解中获益。相比之下，雌性的“保守”策略在高温下无法满足其更高的生殖和自我维持需求，生殖氧化和代谢成本的增加导致个体死亡。生活史权衡策略中的性别差异可直接导致同一物种内环境压力下的“赢家”和“输家”。
