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The global rise of pharmaceutical contaminants in the aquatic environment poses a serious threat to ecological and evolutionary processes. Studies have traditionally focused on the collateral (average) effects of psychoactive pollutants on ecologically relevant behaviors of wildlife, often neglecting effects among and within individuals, and whether they differ between males and females. We tested whether psychoactive pollutants have sex-specific effects on behavioral individuality and plasticity in guppies (Poecilia reticulata), a freshwater species that inhabits contaminated waterways in the wild. Fish were exposed to fluoxetine (Prozac) for 2 years across multiple generations before their activity and stress-related behavior were repeatedly assayed. Using a Bayesian statistical approach that partitions the effects among and within individuals, we found that males—but not females—in fluoxetine-exposed populations differed less from each other in their behavior (lower behavioral individuality) than unexposed males. In sharp contrast, effects on behavioral plasticity were observed in females—but not in males—whereby exposure to even low levels of fluoxetine resulted in a substantial decrease (activity) and increase (freezing behavior) in the behavioral plasticity of females. Our evidence reveals that psychoactive pollution has sex-specific effects on the individual behavior of fish, suggesting that males and females might not be equally vulnerable to global pollutants. [ABSTRACT FROM AUTHOR]

Urbanization can compromise biodiversity as cities expand further into native landscapes. The urban heat island (UHI) describes elevated urban temperatures due to heat retained by built structures (e.g. concrete surfaces). Animal behavior may be critical in determining an animal's ability to thrive in the wake of human disturbance. Yet, we have a relatively poor understanding of how animal behavior is affected by the UHI. We examined sibling cannibalism in urban and desert juvenile black widow spiderling (Latrodectus hesperus) lineages exposed to extreme UHI temperatures (33 °C) or native Sonoran desert temperatures (27 °C). Family of origin had a significant impact on cannibalism, while the effects of temperature and habitat were dependent on spiderling density. Our most pronounced results came at the lower densities of three and two spiderlings. Here habitat and temperature interacted such that spiderlings at 33 °C were consistently more cannibalistic than spiderlings at 27 °C, and this result was consistently stronger for spiderlings from urban families than it was for spiders from desert families. If UHI-induced siblicide promotes the survival and growth of a subset of spiderlings from a clutch, then it might actually foster urban population growth. In contrast, if siblicide in the city simply reduces clutch size, then we might expect the UHI to slow urban infestations. Understanding behavioral phenotypes underlying the explosive population growth of urban pest species will aid in the development of safer and more effective deterrents to infestations, and allow us to better understand the mechanisms shaping urban biodiversity patterns. [ABSTRACT FROM AUTHOR]

Background: Globally, there is growing concern over the impacts of pharmaceuticals and drug manufacturing on aquatic animals, and pharmaceuticals are now recognized as contaminants of emerging environmental concern. In recent years, scientists, environmental managers, and policymakers have been interested in using behavioural endpoints for chemical regulation, given their importance for fitness and survival. The body of research on whether and how pharmaceutical exposure alters the behaviour of aquatic animals has grown exponentially, making it difficult to get an overview of the results. With an international spotlight on the management of these environmental threats, synthesizing the currently available data is vital to inform managers and policymakers, as well as highlighting areas where more research is needed. This is a protocol for a systematic evidence map (SEM) and serves as an a priori record of our objectives and methodological decisions. Our objectives are to identify, catalogue, and present primary research articles on the effects of human and veterinary pharmaceuticals on aquatic animal behaviour. Methods: The literature search will be conducted using two electronic databases: Web of Science and Scopus, and we will supplement these searches with additional sources. The search string has been developed using a Population–Exposure–Comparison–Outcome (PECO) framework, to capture articles that used an aquatic organism (P, population) to test the effects of a pharmaceutical (E, exposure) on behaviour (O, outcome). Eligible articles must also have a control group (C, comparison). Articles will be screened in two stages, title and abstract, followed by full-text screening before data extraction. Decision trees have been designed a priori to appraise articles for eligibility at both stages of screening. At both stages, screening each article will be completed by two independent reviewers. Study validity will be appraised but not used as a basis for article inclusion. The information extracted from the eligible articles, along with bibliometric data, will be mapped and displayed. All data associated with this SEM will be publicly available through the Open Science Framework (OSF) and a future project webpage. [ABSTRACT FROM AUTHOR]

Environmental contamination by pharmaceuticals is global, substantially altering crucial behaviours in animals and impacting on their reproduction and survival. A key question is whether the consequences of these pollutants extend beyond mean behavioural changes, restraining differences in behaviour between individuals. In a controlled, two-year, multigenerational experiment with independent mesocosm populations, we exposed guppies (Poecilia reticulata) to environmentally realistic levels of the ubiquitous pollutant fluoxetine (Prozac). Fish (unexposed: n = 59, low fluoxetine: n = 57, high fluoxetine: n = 58) were repeatedly assayed on four separate occasions for activity and risk-taking behaviour. Fluoxetine homogenized individuals' activity, with individual variation in populations exposed to even low concentrations falling to less than half that in unexposed populations. To understand the proximate mechanism underlying these changes, we tested the relative contribution of variation within and between individuals to the overall decline in individual variation. We found strong evidence that fluoxetine erodes variation in activity between but not within individuals, revealing the hidden consequences of a ubiquitous contaminant on phenotypic variation in fish—likely to impair adaptive potential to environmental change. [ABSTRACT FROM AUTHOR]

• Contamination of the environment with agricultural pollutants is a major issue. • We tested for impacts of the endocrine disruptor 17β-trenbolone on tadpoles. • We found that 17β-trenbolone altered morphology. • It also altered baseline activity and responses to a predatory threat. • However, it did not affect anxiety-like behaviours in a scototaxis assay. Endocrine-disrupting chemicals—compounds that directly interfere with the endocrine system of exposed animals—are insidious environmental pollutants that can disrupt hormone function, even at very low concentrations. The dramatic impacts that some endocrine-disrupting chemicals can have on the reproductive development of wildlife are well documented. However, the potential of endocrine-disrupting chemicals to disrupt animal behaviour has received far less attention, despite the important links between behavioural processes and population-level fitness. Accordingly, we investigated the impacts of 14 and 21-day exposure to two environmentally realistic levels of 17β-trenbolone (4.6 and 11.2 ng/L), a potent endocrine-disrupting steroid and agricultural pollutant, on growth and behaviour in tadpoles of an anuran amphibian, the southern brown tree frog (Litoria ewingii). We found that 17β-trenbolone altered morphology, baseline activity and responses to a predatory threat, but did not affect anxiety-like behaviours in a scototaxis assay. Specifically, we found that tadpoles exposed to our high-17β-trenbolone treatment were significantly longer and heavier at 14 and 21 days. We also found that tadpoles exposed to 17β-trenbolone showed higher levels of baseline activity, and significantly reduced their activity following a simulated predator strike. These results provide insights into the wider repercussions of agricultural pollutants on key developmental and behavioural traits in aquatic species, and demonstrate the importance of behavioural studies in the ecotoxicological field. [ABSTRACT FROM AUTHOR]