MARE - Marine and Environmental Sciences Centre, Laboratório Marítimo da Guia, Faculdade de Ciências da Universidade de Lisboa, Av. Nossa Senhora do Cabo, 939, 2750-374, Cascais, Portugal.
Department of Neuroscience, Physiology Unit, Biomedical Centre (BMC), Uppsala University, Box 593, Uppsala, SE, 75124, Sweden.
Sci Rep. 2019 Sep 4;9(1):12728. doi: 10.1038/s41598-019-49086-0.
Cleaning interactions are textbook examples of mutualisms. On coral reefs, most fishes engage in cooperative interactions with cleaners fishes, where they benefit from ectoparasite reduction and ultimately stress relief. Furthermore, such interactions elicit beneficial effects on clients' ecophysiology. However, the potential effects of future ocean warming (OW) and acidification (OA) on these charismatic associations are unknown. Here we show that a 45-day acclimation period to OW (+3 °C) and OA (980 μatm pCO) decreased interactions between cleaner wrasses (Labroides dimidiatus) and clients (Naso elegans). Cleaners also invested more in the interactions by providing tactile stimulation under OA. Although this form of investment is typically used by cleaners to prolong interactions and reconcile after cheating, interaction time and client jolt rate (a correlate of dishonesty) were not affected by any stressor. In both partners, the dopaminergic (in all brain regions) and serotoninergic (forebrain) systems were significantly altered by these stressors. On the other hand, in cleaners, the interaction with warming ameliorated dopaminergic and serotonergic responses to OA. Dopamine and serotonin correlated positively with motivation to interact and cleaners interaction investment (tactile stimulation). We advocate that such neurobiological changes associated with cleaning behaviour may affect the maintenance of community structures on coral reefs.
清洁互动是互利共生的典型例子。在珊瑚礁中，大多数鱼类与清洁鱼进行合作互动，它们从减少外寄生虫和最终减轻压力中受益。此外，这种互动对客户的生态生理学产生有益的影响。然而，未来海洋变暖（OW）和酸化（OA）对这些魅力四射的关联的潜在影响尚不清楚。在这里，我们表明，45 天的 OW（+3°C）和 OA（980 μatm pCO）适应期降低了清洁濑鱼（Labroides dimidiatus）和客户（Naso elegans）之间的互动。在 OA 下，清洁鱼还通过提供触觉刺激来更多地投资于互动。尽管这种形式的投资通常是由清洁鱼用来延长互动和在欺骗后和解，但互动时间和客户电击率（不诚实的相关指标）不受任何胁迫因素的影响。在两个合作伙伴中，这些胁迫因素显著改变了多巴胺能（所有大脑区域）和血清素能（前脑）系统。另一方面，在清洁鱼中，与变暖的相互作用减轻了 OA 对多巴胺能和血清素能的反应。多巴胺和血清素与互动动机和清洁鱼互动投资（触觉刺激）呈正相关。我们主张，与清洁行为相关的这种神经生物学变化可能会影响珊瑚礁上群落结构的维持。
