SwePub - search: WFRF:(Wong Bob B.M.)

Enumeration	Reference	Cover	Find
1.	Bertram, Michael G., et al. (author) Frontiers in quantifying wildlife behavioural responses to chemical pollution 2022 In: Biological Reviews. - : John Wiley & Sons. - 1464-7931 .- 1469-185X. ; 97:4 Journal article (peer-reviewed)abstract Animal behaviour is remarkably sensitive to disruption by chemical pollution, with widespread implications for ecological and evolutionary processes in contaminated wildlife populations. However, conventional approaches applied to study the impacts of chemical pollutants on wildlife behaviour seldom address the complexity of natural environments in which contamination occurs. The aim of this review is to guide the rapidly developing field of behavioural ecotoxicology towards increased environmental realism, ecological complexity, and mechanistic understanding. We identify research areas in ecology that to date have been largely overlooked within behavioural ecotoxicology but which promise to yield valuable insights, including within- and among-individual variation, social networks and collective behaviour, and multi-stressor interactions. Further, we feature methodological and technological innovations that enable the collection of data on pollutant-induced behavioural changes at an unprecedented resolution and scale in the laboratory and the field. In an era of rapid environmental change, there is an urgent need to advance our understanding of the real-world impacts of chemical pollution on wildlife behaviour. This review therefore provides a roadmap of the major outstanding questions in behavioural ecotoxicology and highlights the need for increased cross-talk with other disciplines in order to find the answers.
2.	Brand, Jack A., et al. (author) Temperature change exerts sex-specific effects on behavioural variation 2023 In: Proceedings of the Royal Society of London. Biological Sciences. - 0962-8452 .- 1471-2954. ; 290:2002 Journal article (peer-reviewed)abstract Temperature is a key factor mediating organismal fitness and has important consequences for species' ecology. While the mean effects of temperature on behaviour have been well-documented in ectotherms, how temperature alters behavioural variation among and within individuals, and whether this differs between the sexes, remains unclear. Such effects likely have ecological and evolutionary consequences, given that selection acts at the individual level. We investigated the effect of temperature on individual-level behavioural variation and metabolism in adult male and female Drosophila melanogaster (n = 129), by taking repeated measures of locomotor activity and metabolic rate at both a standard temperature (25°C) and a high temperature (28°C). Males were moderately more responsive in their mean activity levels to temperature change when compared to females. However, this was not true for either standard or active metabolic rate, where no sex differences in thermal metabolic plasticity were found. Furthermore, higher temperatures increased both among- and within-individual variation in male, but not female, locomotor activity. Given that behavioural variation can be critical to population persistence, we suggest that future studies test whether sex differences in the amount of behavioural variation expressed in response to temperature change may result in sex-specific vulnerabilities to a warming climate.
3.	Brodin, Tomas, et al. (author) The urgent need for designing greener drugs 2024 In: Nature Sustainability. - 2398-9629. Journal article (other academic/artistic)abstract The pervasive contamination of ecosystems with active pharmaceutical ingredients poses a serious threat to biodiversity, ecosystem services and public health. Urgent action is needed to design greener drugs that maintain efficacy but also minimize environmental impact.
4.	Dyer, Adrian G, et al. (author) Parallel evolution of angiosperm colour signals : common evolutionary pressures linked to hymenopteran vision. 2012 In: Proceedings of the Royal Society of London. Biological Sciences. - : The Royal Society. - 0962-8452 .- 1471-2954. ; 279:1742, s. 3606-15 Journal article (peer-reviewed)abstract Flowering plants in Australia have been geographically isolated for more than 34 million years. In the Northern Hemisphere, previous work has revealed a close fit between the optimal discrimination capabilities of hymenopteran pollinators and the flower colours that have most frequently evolved. We collected spectral data from 111 Australian native flowers and tested signal appearance considering the colour discrimination capabilities of potentially important pollinators. The highest frequency of flower reflectance curves is consistent with data reported for the Northern Hemisphere. The subsequent mapping of Australian flower reflectances into a bee colour space reveals a very similar distribution of flower colour evolution to the Northern Hemisphere. Thus, flowering plants in Australia are likely to have independently evolved spectral signals that maximize colour discrimination by hymenoptera. Moreover, we found that the degree of variability in flower coloration for particular angiosperm species matched the range of reflectance colours that can only be discriminated by bees that have experienced differential conditioning. This observation suggests a requirement for plasticity in the nervous systems of pollinators to allow generalization of flowers of the same species while overcoming the possible presence of non-rewarding flower mimics.
5.	Ford, Alex T., et al. (author) The Role of Behavioral Ecotoxicology in Environmental Protection 2021 In: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 55:9, s. 5620-5628 Journal article (peer-reviewed)abstract For decades, we have known that chemicals affect human and wildlife behavior. Moreover, due to recent technological and computational advances, scientists are now increasingly aware that a wide variety of contaminants and other environmental stressors adversely affect organismal behavior and subsequent ecological outcomes in terrestrial and aquatic ecosystems. There is also a groundswell of concern that regulatory ecotoxicology does not adequately consider behavior, primarily due to a lack of standardized toxicity methods. This has, in turn, led to the exclusion of many behavioral ecotoxicology studies from chemical risk assessments. To improve understanding of the challenges and opportunities for behavioral ecotoxicology within regulatory toxicology/risk assessment, a unique workshop with international representatives from the fields of behavioral ecology, ecotoxicology, regulatory (eco)toxicology, neurotoxicology, test standardization, and risk assessment resulted in the formation of consensus perspectives and recommendations, which promise to serve as a roadmap to advance interfaces among the basic and translational sciences, and regulatory practices.
6.	Lagesson, Annelie, et al. (author) Fish on steroids : Temperature-dependent effects of 17β-trenbolone on predator escape, boldness, and exploratory behaviors 2019 In: Environmental Pollution. - : Elsevier. - 0269-7491 .- 1873-6424. ; 245, s. 243-252 Journal article (peer-reviewed)abstract Hormonal growth promoters (HGPs), widely used in beef cattle production globally, make their way into the environment as agricultural effluent—with potential impacts on aquatic ecosystems. One HPG of particular concern is 17β-trenbolone, which is persistent in freshwater habitats and can affect the development, morphology and reproductive behaviors of aquatic organisms. Despite this, few studies have investigated impacts of 17β-trenbolone on non-reproductive behaviors linked to growth and survival, like boldness and predator avoidance. None consider the interaction between 17β-trenbolone and other environmental stressors, such as temperature, although environmental challenges confronting animals in the wild seldom, if ever, occur in isolation. Accordingly, this study aimed to test the interactive effects of trenbolone and temperature on organismal behavior. To do this, eastern mosquitofish (Gambusia holbrooki) were subjected to an environmentally-relevant concentration of 17β-trenbolone (average measured concentration 3.0 ± 0.2 ng/L) or freshwater (i.e. control) for 21 days under one of two temperatures (20 and 30 °C), after which the predator escape, boldness and exploration behavior of fish were tested. Predator escape behavior was assayed by subjecting fish to a simulated predator strike, while boldness and exploration were assessed in a separate maze experiment. We found that trenbolone exposure increased boldness behavior. Interestingly, some behavioral effects of trenbolone depended on temperature, sex, or both. Specifically, significant effects of trenbolone on male predator escape behavior were only noted at 30 °C, with males becoming less reactive to the simulated threat. Further, in the maze experiment, trenbolone-exposed fish explored the maze faster than control fish, but only at 20 °C. We conclude that field detected concentrations of 17β-trenbolone can impact ecologically important behaviors of fish, and such effects can be temperature dependent. Such findings underscore the importance of considering the potentially interactive effects of other environmental stressors when investigating behavioral effects of environmental contaminants.
7.	Lehtonen, Topi K., et al. (author) Adjustment of brood care behaviour in the absence of a mate in two species of Nicaraguan crater lake cichlids 2011 In: Behavioral Ecology and Sociobiology. - : Springer Science and Business Media LLC. - 0340-5443 .- 1432-0762. ; 65:4, s. 613-619 Journal article (peer-reviewed)abstract In many taxa, parental strategies can vary among individuals. This is especially true in species with biparental care, with males, more often than females, deserting their mates. While there is an abundance of theoretical predictions and empirical data on factors inducing mate abandonment by males, much less is known about what consequences this may have on female behaviour, particularly in the field and in non-avian systems. Here, we compared brood defence rate, behavioural defence types, and brood success of solitary and paired females in two species of Neotropical cichlid fish in their natural habitat. In terms of the rate of territorial aggression towards potential brood predators, solitary females were able to fully compensate in the absence of a male but, in so doing, ended up maintaining smaller territories, which appeared to compromise offspring fitness in at least one of the two species. Hence, our results suggest that even extensive quantitative compensation in parental effort by solitary females may not be enough to ensure adequate qualitative compensation for the lack of male participation, highlighting the importance of distinguishing between these two aspects of compensatory parental care.
8.	Lehtonen, Topi K., et al. (author) Aggressive desert goby males also court more, independent of the physiological demands of salinity 2018 In: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 8 Journal article (peer-reviewed)abstract Both between- and within-individual variation in behaviour can be important in determining mating opportunities and reproductive outcomes. Such behavioural variability can be induced by environmental conditions, especially if individuals vary in their tolerance levels or resource allocation patterns. We tested the effects of exposure to different salinity levels on male investment into two important components of mating success-intrasexual aggression and intersexual courtship-in a fish with a resource defence mating system, the desert goby, Chlamydogobius eremius. We found that males that were more aggressive to rivals also exhibited higher rates of courtship displays towards females. Contrary to predictions, this positive relationship, and the consistency of the two behaviours, were not affected by the salinity treatment, despite the physiological costs that high salinity imposes on the species. Moreover, over the entire data-set, there was only a marginally non-significant tendency for males to show higher levels of aggression and courtship in low, than high, salinity. The positive correlation between male aggression and courtship, independent of the physiological demands of the environment, suggests that males are not inclined to make contrasting resource investments into these two key reproductive behaviours. Instead, in this relatively euryhaline freshwater species, typical investment into current reproductive behaviours can occur under a range of different salinity conditions.
9.	Lehtonen, Topi K., et al. (author) Both male and female identity influence variation in male signalling effort 2011 In: BMC Evolutionary Biology. - : Springer Science and Business Media LLC. - 1471-2148. ; 11 Journal article (peer-reviewed)abstract Background: Male sexual displays play an important role in sexual selection by affecting reproductive success. However, for such displays to be useful for female mate choice, courtship should vary more among than within individual males. In this regard, a potentially important source of within male variation is adjustment of male courtship effort in response to female traits. Accordingly, we set out to dissect sources of variation in male courtship effort in a fish, the desert goby (Chlamydogobius eremius). We did so by designing an experiment that allowed simultaneous estimation of within and between male variation in courtship, while also assessing the importance of the males and females as sources of courtship variation. Results: Although males adjusted their courtship depending on the identity of the female (a potentially important source of within-male variation), among-male differences were considerably greater. In addition, male courtship effort towards a pair of females was highly repeatable over a short time frame. Conclusion: Despite the plasticity in male courtship effort, courtship displays had the potential to reliably convey information about the male to mate-searching females. Our experiment therefore underscores the importance of addressing the different sources contributing to variation in the expression of sexually-selected traits.
10.	Lehtonen, Topi K., et al. (author) Effects of salinity on nest-building behaviour in a marine fish 2016 In: BMC Ecology. - : Springer Science and Business Media LLC. - 1472-6785. ; 16 Journal article (peer-reviewed)abstract Background: Parental allocation and reproductive success are often strongly influenced by environmental factors. In this respect, salinity is a key factor influencing species distributions and community structure in aquatic animals. Nevertheless, the effects of salinity on reproductive behaviours are not well known. Here, we used the sand goby (Pomatoschistus minutus), a small fish inhabiting a range of different salinities, to experimentally assess the effects of changes in salinity on nesting behaviour, a key component of reproduction in sand gobies and many other taxa. Results: We found that salinity levels influenced some aspects of male nesting behaviour (i.e. nest entrance size) but not others (i.e. latency to build a nest, choice of nest site, sand on top of nest) and that small and large individuals were differently affected. In particular, the importance of body size in adjustment of nest entrance depended on the salinity level. Conclusion: The results support the prediction that geographically widespread aquatic species, such as sand gobies, are able to perform well under a range of salinity levels. The phenotype by environment interaction found between male size and behavioural responses to salinity can, in turn, help to explain the notable variation observed in nest-building (and other) behaviours closely linked to reproduction.
11.	Lehtonen, Topi K., et al. (author) The influence of recent social experience and physical environment on courtship and male aggression 2016 In: BMC Evolutionary Biology. - : Springer Science and Business Media LLC. - 1471-2148. ; 16 Journal article (peer-reviewed)abstract Background: Social and environmental factors can profoundly impact an individual's investment of resources into different components of reproduction. Such allocation trade-offs are expected to be amplified under challenging environmental conditions. To test these predictions, we used a desert-dwelling fish, the desert goby, Chlamydogobius eremius, to experimentally investigate the effects of prior social experience (with either a male or a female) on male investment in courtship and aggression under physiologically benign and challenging conditions (i.e., low versus high salinity). Results: We found that males maintained a higher level of aggression towards a rival after a recent encounter with a female, compared to an encounter with a male, under low (but not high) salinity. In contrast, male investment in courtship behaviour was unaffected by either salinity or social experience. Conclusion: Together, our results suggest that male investment in aggression and courtship displays can differ in their sensitivity to environmental conditions and that not all reproductive behaviours are similarly influenced by the same environmental context.
12.	Orford, Jack T., et al. (author) Bigger and bolder : Widespread agricultural pollutant 17β-trenbolone increases growth and alters behaviour in tadpoles (Litoria ewingii) 2023 In: Aquatic Toxicology. - 0166-445X .- 1879-1514. ; 260 Journal article (peer-reviewed)abstract 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.
13.	Orford, Jack T., et al. (author) Impacts of Exposure to Ultraviolet Radiation and an Agricultural Pollutant on Morphology and Behavior of Tadpoles (Limnodynastes tasmaniensis) 2024 In: Environmental Toxicology and Chemistry. - 0730-7268 .- 1552-8618. ; 43:7, s. 1615-1626 Journal article (peer-reviewed)abstract Amphibians are the most threatened vertebrate class globally. Multiple factors have been implicated in their global decline, and it has been hypothesized that interactions between stressors may be a major cause. Increased ultraviolet (UV) radiation, as a result of ozone depletion, has been identified as one such stressor. Exposure to UV radiation has been shown to have detrimental effects on amphibians and can exacerbate the effects of other stressors, such as chemical pollutants. Chemical pollution has likewise been recognized as a major factor contributing to amphibian declines, particularly, endocrine-disrupting chemicals. In this regard, 17 beta-trenbolone is a potent anabolic steroid used in the agricultural industry to increase muscle mass in cattle and has been repeatedly detected in the environment where amphibians live and breed. At high concentrations, 17 beta-trenbolone has been shown to impact amphibian survival and gonadal development. In the present study, we investigated the effects of environmentally realistic UV radiation and 17 beta-trenbolone exposure, both in isolation and in combination, on the morphology and behavior of tadpoles (Limnodynastes tasmaniensis). We found that neither stressor in isolation affected tadpoles, nor did we find any interactive effects. The results from our 17 beta-trenbolone treatment are consistent with recent research suggesting that, at environmentally realistic concentrations, tadpoles may be less vulnerable to this pollutant compared to other vertebrate classes. The absence of UV radiation-induced effects found in the present study could be due to species-specific variation in susceptibility, as well as the dosage utilized. We suggest that future research should incorporate long-term studies with multiple stressors to accurately identify the threats to, and subsequent consequences for, amphibians under natural conditions. Environ Toxicol Chem 2024;00:1-12. (c) 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
14.	Polverino, Giovanni, et al. (author) Sex-specific effects of psychoactive pollution on behavioral individuality and plasticity in fish 2023 In: Behavioral Ecology. - 1045-2249 .- 1465-7279. ; 34:6, s. 969-978 Journal article (peer-reviewed)abstract Lay Summary Prozac is present in freshwater systems across the globe as the pharmaceutical contaminant fluoxetine. The effect of fluoxetine on aquatic species' behavioral variability is not yet clear. We show that male guppies become more similar to each other after exposure to fluoxetine, and females become less flexible in their behavior. These sex-specific differences in response to fluoxetine can have a meaningful impact on their ability to survive in a changing world. 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.
15.	Saaristo, Minna, et al. (author) Behavioural effects of psychoactive pharmaceutical exposure on European perch (Perca fluviatilis) in a multi-stressor environment 2019 In: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 655, s. 1311-1320 Journal article (peer-reviewed)abstract With the ability to resist biodegradation and exert therapeutic effects at low concentrations, pharmaceutical contaminants have become environmental stressors for wildlife. One such contaminant is the anxiolytic oxazepam, a psychoactive pharmaceutical that is frequently detected in surface waters globally. Despite growing interest in understanding how wildlife respond to anxiolytics, synergistic effects of pharmaceuticals and other abiotic (e.g. temperature) and biotic (e.g. predation risk) stressors remain unclear. Here, using a multi-stressor approach, we investigated effects of 7-day oxazepam exposure (6.5 μg/L) on anxiety-related behaviours in juvenile European perch (Perca fluviatilis). The multi-stressor approach was achieved by exposing perch to oxazepam at two temperatures (10 °C and 18 °C), and at two predation risk regimes—generated using chemical cues from the northern pike (Esox lucius). Our exposures resulted in a successful uptake of the drug from the water, i.e., oxazepam was measured in perch muscle tissue at 50 ± 17 ng/g (mean ± SD). We found significant oxazepam-induced effects on boldness, with 76.7% of the treated fish entering the white background (i.e. ‘exposed’ area where exposure to presumed risks are higher) within the first 5 min, compared to 66.6% of the control fish. We also found a significant effect of temperature on total time spent freezing (i.e. staying motionless). Specifically, fish in the low temperature treatments (oxazepam, predation) froze for longer than fish in high temperatures. Our multi-stressor study is the first to uncover how anxiety-related behaviours in wild juvenile fish are altered by changes in water temperature and perceived predation risk. Importantly, our findings highlight the need to focus on multiple stressors to improve understanding of how organisms not only survive, but adapt to, human-induced environmental change.
16.	Saaristo, Minna, et al. (author) Behavioural effects of temperature, predation-risk and anxiolytic exposure on the European perch (Perca fluviatilis) 2018 Other publication (other academic/artistic)abstract With the ability to resist biodegradation and exert therapeutic effects at low concentrations, emerging contaminants have become environmental stressors for wildlife. One such contaminant is the anxiolytic oxazepam, a psychoactive pharmaceutical which is frequently detected in surface waters globally. Despite the growing interest in understanding how wildlife responds to such contaminants, the synergistic fitness effects of pharmaceuticals and increased variability in temperature remain unclear. Here, by using a multi-stressor approach, we investigated the effects of 7-d oxazepam exposure (6.5 μg/L) on anxiety-related behaviours in juvenile European perch (Perca fluviatilis). The multi-stressor approach was achieved by exposing perch to oxazepam at either low (10°C) or high (18°C) temperature, with or without a predation cue, generating 8 treatments. Our exposures resulted in a successful uptake of the drug from the water, i.e. oxazepam was measured at muscle tissue concentrations around 50 ± 17 ng/g (mean ± SD). We found significant effects on boldness induced by the studied drug: 92.8% of the fish in the 'oxazepam and predation and high temperature' treatment entered the white background (representing a novel area where exposure to presumed risks are higher) within the first 5 min, compared to 79.3% of the 'control and predation and high temperature' fish. We also found a significant effect on temperature on the total time freezing (i.e. staying motionless). Specifically, fish in the low temperature treatments (oxazepam, predation and control) froze for longer than fish in the high temperatures, respectively. Our study is the first to show altered anxiety-related behaviours in a native juvenile fish resulting from oxazepam, predation and high temperature. As adaptation to a range of biotic and abiotic pressures is essential to living organisms, our study highlights the need to focus on multiple stressors to improve understanding of how organisms not only survive, but adapt to human-induced environmental change.
17.	Saaristo, Minna, et al. (author) Direct and indirect effects of chemical contaminants on the behaviour, ecology and evolution of wildlife 2018 In: Proceedings of the Royal Society of London. Biological Sciences. - : ROYAL SOC. - 0962-8452 .- 1471-2954. ; 285:1885 Research review (peer-reviewed)abstract Chemical contaminants (e.g. metals, pesticides, pharmaceuticals) are changing ecosystems via effects on wildlife. Indeed, recent work explicitly performed under environmentally realistic conditions reveals that chemical contaminants can have both direct and indirect effects at multiple levels of organization by influencing animal behaviour. Altered behaviour reflects multiple physiological changes and links individual-to population-level processes, thereby representing a sensitive tool for holistically assessing impacts of environmentally relevant contaminant concentrations. Here, we show that even if direct effects of contaminants on behavioural responses are reasonably well documented, there are significant knowledge gaps in understanding both the plasticity (i.e. individual variation) and evolution of contaminant-induced behavioural changes. We explore implications of multi-level processes by developing a conceptual framework that integrates direct and indirect effects on behaviour under environmentally realistic contexts. Our framework illustrates how sublethal behavioural effects of contaminants can be both negative and positive, varying dynamically within the same individuals and populations. This is because linkages within communities will act indirectly to alter and even magnify contaminant-induced effects. Given the increasing pressure on wildlife and ecosystems from chemical pollution, we argue there is a need to incorporate existing knowledge in ecology and evolution to improve ecological hazard and risk assessments.
18.	Sowersby, Will, et al. (author) Resource trait specialisation in an introduced fish population with reduced genetic diversity 2020 In: Biological Invasions. - : Springer Science and Business Media LLC. - 1387-3547 .- 1573-1464. ; 22:8, s. 2447-2460 Journal article (peer-reviewed)abstract Ecological specialisation is hypothesised to play a major role in the evolution of phenotypic diversity, especially following the colonisation of novel habitats. For example, cichlid fishes provide some of the most remarkable evidence for rapid ecological diversification. Here, we capitalised on a recently (<= 40 years ago) introduced population of red devils (Amphilophus labiatus) in Australia to investigate adaptive phenotypic responses to a novel environment. We used stomach content analyses, morphometrics and laboratory experiments to test for covariation between diet and size of an important trophic trait, lip size. We found that, while maximum lip size in the study population was smaller than in the species' natural range, the proportions of algae, insects and fish remains in the diet covaried with lip size. However, contrary to predictions, we found no evidence for lip development to be plastic under laboratory conditions in relation to substrate complexity or food manipulation, nor did we find any relationship between lip morphology and feeding performance in adults. Single nucleotide polymorphism data, in turn, suggested that the introduced population has reduced standing genetic variation, which potentially influences both phenotypic plasticity and diversity, in comparison to native populations. Together, the results suggest that morphological variation in a key trophic trait can respond rapidly to diet in a novel environment, despite reduced genetic diversity in the population.
19.	Sowersby, Will, et al. (author) Temporal and sex-specific patterns of breeding territory defense in a color-polymorphic cichlid fish 2017 In: Hydrobiologia. - : Springer Science and Business Media LLC. - 0018-8158 .- 1573-5117. ; 791:1, s. 237-245 Journal article (peer-reviewed)abstract In biparental species, the costs and benefits of parental investment can vary between the sexes and shift over time. However, such sex-specific and temporal changes in territory defense are not well understood. Here, we experimentally investigated parental investment in breeding territory defense in a feral population of the color-polymorphic, biparental cichlid fish, the red devil (Amphilophus labiatus). We presented either gold- or dark-colored conspecific intruder models (i.e., dummy models) to A. labiatus pairs at three key stages during the breeding cycle (i.e., after pair formation, after eggs have been laid, and when fry were free-swimming). We found that males were more aggressive when the pair first formed, whereas females significantly increased their territory defense with time, and were most aggressive when fry were free-swimming. These results show that parental roles in territory defense can markedly shift over key stages of the breeding cycle. Our results demonstrate that parental behaviors may not only vary between the sexes, but can also shift dramatically over the course of the brood cycle.
20.	Svensson, P. Andreas, 1973-, et al. (author) A high aggression strategy for smaller males 2012 Conference paper (peer-reviewed)abstract Male-male conflict is common among animals, but questions remain as to when, how and by whom aggression should be initiated. Factors that affect agonistic strategies include residency, the value of the contested resource and the fighting ability of the contestants. Game-theoretical models often assume that strategies for aggression are conditional and shaped by mutual assessment. We quantified aggression in a fish, the Australian desert goby, Chlamydogobius eremius, by exposing nest-holding males to male intruders. The perceived value of the resource (the nest) was manipulated by exposing half of the residents to sexually receptive females before the trial. We found resident male aggression to be unaffected by perceived mating opportunities. It was also unaffected by the size of the intruder. Instead, aggression was related the residents' own size, namely, smaller males attacked sooner and with greater intensity than larger males. Thus, contrary to theory, resident desert goby males appeared to have set strategies for initiating aggression. Rather than viewing high aggression in small males as a paradox (i.e. the Napoleon effect), we suggest that small individuals may benefit from attacking early, before an intruder has time to assess the resident and/or the resource.
21.	Svensson, P. Andreas, 1973-, et al. (author) A high aggression strategy for smaller males 2012 In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 7:8 Journal article (peer-reviewed)abstract Male-male conflict is common among animals, but questions remain as to when, how and by whom aggression should be initiated. Factors that affect agonistic strategies include residency, the value of the contested resource and the fighting ability of the two contestants. We quantified initiation of aggression in a fish, the desert goby, Chlamydogobius eremius, by exposing nest-holding males to a male intruder. The perceived value of the resource ( the nest) was manipulated by exposing half of the residents to sexually receptive females for two days before the trial. Resident male aggression, however, was unaffected by perceived mating opportunities. It was also unaffected by the absolute and relative size of the intruder. Instead resident aggression was negatively related to resident male size. In particular, smaller residents attacked sooner and with greater intensity compared to larger residents. These results suggest that resident desert goby males used set, rather than conditional, strategies for initiating aggression. If intruders are more likely to flee than retaliate, small males may benefit from attacking intruders before these have had an opportunity to assess the resident and/or the resource.
22.	Tan, Hung, et al. (author) No evidence that the widespread environmental contaminant caffeine alters energy balance or stress responses in fish 2023 In: Ethology. - 0179-1613 .- 1439-0310. ; 129:12, s. 666-678 Journal article (peer-reviewed)abstract Anthropogenic sources of environmental pollution are ever-increasing as urban areas expand and more chemical compounds are used in daily life. The stimulant caffeine is one of the most consumed chemical compounds worldwide, and as a result, has been detected as an environmental contaminant in all types of major water sources on all continents. Exposure of wildlife to environmental pollutants can disrupt the energy balance of these organisms, as restoration of homeostasis is prioritised. In turn, energy allocated to other key biological processes such as growth or reproduction may be affected, consequently reducing the overall fitness of an individual. Therefore, we aimed to investigate if long-term exposure to environmentally relevant concentrations of caffeine had any energetic consequences on wildlife. Specifically, we exposed wild eastern mosquitofish (Gambusia holbrooki) to one of three nominal concentrations of caffeine (0, 100 and 10,000 ng/L) and assayed individuals for metabolic rate, general activity, antipredator and foraging behaviour and body size as measures of energy expenditure or energy intake. We found no differences in any measured traits between any of the given exposure treatments, indicating that exposure to caffeine at current environmental levels may not adversely affect the energy balance and fitness of vulnerable freshwater fish.
23.	Tan, Hung, et al. (author) Widespread psychoactive pollutant augments daytime restfulness and disrupts diurnal activity rhythms in fish 2023 In: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 326 Journal article (peer-reviewed)abstract Pharmaceutical pollution is a major driver of global change, with the capacity to alter key behavioural and physiological traits in exposed animals. Antidepressants are among the most commonly detected pharmaceuticals in the environment. Despite well-documented pharmacological effects of antidepressants on sleep in humans and other vertebrates, very little is known about their ecologically relevant impacts as pollutants on non-target wildlife. Accordingly, we investigated the effects of acute 3-day exposure of eastern mosquitofish (Gambusia holbrooki) to field-realistic levels (nominal concentrations: 30 and 300 ng/L) of the widespread psychoactive pollutant, fluoxetine, on diurnal activity patterns and restfulness, as indicators of disruptions to sleep. We show that exposure to fluoxetine disrupted diel activity patterns, which was driven by augmentation of daytime inactivity. Specifically, unexposed control fish were markedly diurnal, swimming farther during the day and exhibiting longer periods and more bouts of inactivity at night. However, in fluoxetine-exposed fish, this natural diel rhythm was eroded, with no differences in activity or restfulness observed between the day and night. As a misalignment in the circadian rhythm has been shown to adversely affect fecundity and lifespan in animals, our findings reveal a potentially serious threat to the survival and reproductive success of pollutant-exposed wildlife.

Skapa referenser, mejla, bekava och länka

Permalink

Träfflista för sökning "WFRF:(Wong Bob B.M.) "

Refine your search

Year