Lofeu Leandro, Bonini-Campos Bianca, Kohlsdorf Tiana
Department of Biology, FFCLRP, University of São Paulo, São Paulo, Brazil.
Front Cell Dev Biol. 2025 Jul 7;13:1531162. doi: 10.3389/fcell.2025.1531162. eCollection 2025.
Plastic phenotypes result from multidimensional developmental systems responding to distinct yet simultaneous environmental signals, which may differently affect the magnitude and directions of plastic responses.Concomitant environmental signals during development may result in dominant, synergistic, or even antagonistic phenotypic effects, so that a given condition may amplify or minimize plastic responses to other environmental stimuli. Knowledge on how external information shapes complex plastic phenotypes is essential to predict potential evolutionary trajectories driven by developmental plasticity.
Here, we manipulate water temperature to evaluate its effects on the well-described phenotypic accommodation of fish growth in the presence of water flow, using the neotropical species . We include larval and juvenile ontogenetic stages to examine the interaction between these two environmental signals in plastic responses related to body size and shape, skeleton ossification and gene expression, using as a proxy for ossification pathways.
Our results demonstrate that water temperature plays a crucial role determining the expression of plastic variation at all dimensions, and effects of water flow were restricted to specific thermal regimes. Combination of high temperature and water flow has a major effect on body shape and unveils unique phenotypic patterns, supporting the prediction that high temperatures can amplify plastic responses to external signals. Specifically, fish raised in the presence of water flow at warmer environments grew faster and ossified earlier, and this condition increased expression levels especially at later developmental stages. Such plastic phenotypes likely involve a functional relationship with swimming performance in running-water environments. Our findings highlight the importance of studying developmental plasticity in complex environments using a multidimensional approach, especially considering increments in water temperatures due to accelerated climate changes that likely impact the fish developmental potential to mitigate environmental changes through plastic responses.
可塑性表型源自多维度发育系统对不同但同时存在的环境信号做出的反应，这些信号可能会对可塑性反应的幅度和方向产生不同影响。发育过程中伴随出现的环境信号可能会导致显性、协同甚至拮抗的表型效应，从而使给定条件可能会放大或最小化对其他环境刺激的可塑性反应。了解外部信息如何塑造复杂的可塑性表型对于预测由发育可塑性驱动的潜在进化轨迹至关重要。
在此，我们通过操纵水温来评估其在水流存在的情况下对已充分描述的鱼类生长表型适应的影响，使用新热带物种。我们纳入了幼体和幼年期个体发育阶段，以研究这两种环境信号在与体型和形状、骨骼骨化及基因表达相关的可塑性反应中的相互作用，使用作为骨化途径的代表。
我们的结果表明，水温在决定所有维度上可塑性变异的表达方面起着关键作用，而水流的影响仅限于特定的热状态。高温与水流的组合对体型有重大影响，并揭示了独特的表型模式，支持了高温可放大对外部信号的可塑性反应这一预测。具体而言，在较温暖环境中水流存在的情况下饲养的鱼类生长更快且骨化更早，这种条件尤其在发育后期增加了表达水平。这种可塑性表型可能与流水环境中的游泳性能存在功能关系。我们的研究结果强调了使用多维度方法研究复杂环境中发育可塑性的重要性，特别是考虑到由于气候变化加速导致水温升高，这可能会影响鱼类通过可塑性反应减轻环境变化的发育潜力。
