Abstract:
Ongoing climate change poses an increasing threat to biodiversity. To avoid decline or extinction, species need to either adjust or adapt to new environmental conditions or track their climatic niches across space. In sessile organisms such as plants, phenotypic plasticity can help maintain fitness in variable and even novel environmental conditions and is therefore likely to play an important role in allowing them to survive climate change, particularly in the short term. Understanding a species\' response to rising temperature is crucial for planning well-targeted and cost-effective conservation measures. We sampled seeds of three Hypericum species (H. maculatum, H. montanum, and H. perforatum), from a total of 23 populations originating from different parts of their native distribution areas in Europe. We grew them under four different temperature regimes in a greenhouse to simulate current and predicted future climatic conditions in the distribution areas. We measured flowering start, flower count, and subsequent seed weight, allowing us to study variations in the thermal plasticity of flowering phenology and its relation to fitness. Our results show that individuals flowered earlier with increasing temperature, while the degree of phenological plasticity varied among species. More specifically, the plasticity of H. maculatum varied depending on population origin, with individuals from the leading range edge being less plastic. Importantly, we show a positive relationship between higher plasticity and increased flower production, indicating adaptive phenological plasticity. The observed connection between plasticity and fitness supports the idea that plasticity may be adaptive. This study underlines the need for information on plasticity for predicting species\' potential to thrive under global change and the need for studies on whether higher phenotypic plasticity is currently being selected as natural populations experience a rapidly changing climate.
摘要:
持续的气候变化对生物多样性构成了越来越大的威胁。为了避免衰落或灭绝,物种需要调整或适应新的环境条件,或者跨空间跟踪其气候生态位。在固着生物如植物中,表型可塑性可以帮助在可变甚至新颖的环境条件下保持适应性,因此可能在允许它们在气候变化中生存的过程中发挥重要作用,特别是在短期内。了解物种对温度升高的反应对于计划有针对性和具有成本效益的保护措施至关重要。我们采样了三种金丝桃属物种的种子(H。黄斑,H.Montanum,和穿孔虫H),来自来自欧洲本土分布区不同地区的23个种群。我们在温室中的四种不同温度条件下种植它们,以模拟分布区域当前和预测的未来气候条件。我们测量了开花开始,花计数,以及随后的种子重量,使我们能够研究开花物候的热可塑性变化及其与适应性的关系。我们的结果表明,随着温度的升高,个体开花更早,而物候可塑性的程度因物种而异。更具体地说,黄斑H.maculatum的可塑性因种群来源而异,与个人从领先的范围是较少的塑料。重要的是,我们显示了较高的可塑性和增加的花卉产量之间的正相关关系,表明适应性物候可塑性。观察到的可塑性和适应性之间的联系支持可塑性可能是自适应的想法。这项研究强调了对预测物种在全球变化下茁壮成长的潜力的可塑性信息的需求,以及对随着自然种群经历快速变化的气候,目前是否正在选择更高的表型可塑性进行研究的必要性。