Browsing by Subject "AVOIDANCE"

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  • Kämppi, Antti; Tanner, Tarja; Viitanen, Olavi; Pohjola, Vesa; Päkkilä, Jari; Tjäderhane, Leo; Anttonen, Vuokko; Patinen, Pertti (2022)
    The main aim of this cross-sectional study was to examine the prevalence of dental fear among Finnish conscripts. Other aims were to study the association between dental fear and cariological status as well as their self-reported, dentition-related well-being. The study material consisted of 13,564 men and 255 women conscripts who underwent oral examinations. Of those, 8713 responded to a computer-based questionnaire. The mean number of decayed teeth (DT) was used in analyses for cariological status. Self-reported dental fear, dentition-related well-being and regular check-ups were analysed. Data were analysed with cross tables, Pearson Chi-Square tests, Fisher's exact test and binary logistic regressive analysis. High dental fear or finding dental visits very scary was associated with DT > 2 both among women (14.6%, when DT = 0; 33.3%, when DT > 2) and men conscripts (2.3% and 10.8%, respectively). In addition, those reporting that dental health had a negative impact on their well-being and had no regular check-ups were more likely to need cariological treatment than the rest. A high education level, both one's own and parental, was a protective factor for restorative treatment need in male conscripts. The findings of this study support the concept of a vicious cycle of dental fear and dental caries. A preventive, interactive way of work by dental teams would most likely be beneficial for dental health, avoiding the development of dental fear, and dentition-related well-being.
  • Kikuchi, David W.; Waldron, Samuel J.; Valkonen, Janne K.; Dobler, Susanne; Mappes, Johanna (2020)
    Mullerian mimicry is a classic example of adaptation, yet Muller's original theory does not account for the diversity often observed in mimicry rings. Here, we aimed to assess how well classical Mullerian mimicry can account for the colour polymorphism found in chemically defended Oreina leaf beetles by using field data and laboratory assays of predator behaviour. We also evaluated the hypothesis that thermoregulation can explain diversity between Oreina mimicry rings. We found that frequencies of each colour morph were positively correlated among species, a critical prediction of Mullerian mimicry. Predators learned to associate colour with chemical defences. Learned avoidance of the green morph of one species protected green morphs of another species. Avoidance of blue morphs was completely generalized to green morphs, but surprisingly, avoidance of green morphs was less generalized to blue morphs. This asymmetrical generalization should favour green morphs: indeed, green morphs persist in blue communities, whereas blue morphs are entirely excluded from green communities. We did not find a correlation between elevation and coloration, rejecting thermoregulation as an explanation for diversity between mimicry rings. Biased predation could explain within-community diversity in warning coloration, providing a solution to a long-standing puzzle. We propose testable hypotheses for why asymmetric generalization occurs, and how predators maintain the predominance of blue morphs in a community, despite asymmetric generalization.
  • Nokelainen, Ossi; Rezende, Francisko de Moraes; Valkonen, Janne K.; Mappes, Johanna (2022)
    A big question in behavioral ecology is what drives diversity of color signals. One possible explanation is that environmental conditions, such as light environment, may alter visual signaling of prey, which could affect predator decision-making. Here, we tested the context-dependent predator selection on prey coloration. In the first experiment, we tested detectability of artificial visual stimuli to blue tits (Cyanistes caeruleus) by manipulating stimulus luminance and chromatic context of the background. We expected the presence of the chromatic context to facilitate faster target detection. As expected, blue tits found targets on chromatic yellow background faster than on achromatic grey background whereas in the latter, targets were found with smaller contrast differences to the background. In the second experiment, we tested the effect of two light environments on the survival of aposematic, color polymorphic wood tiger moth (Arctia plantaginis). As luminance contrast should be more detectable than chromatic contrast in low light intensities, we expected birds, if they find the moths aversive, to avoid the white morph which is more conspicuous than the yellow morph in low light (and vice versa in bright light). Alternatively, birds may attack first moths that are more detectable. We found birds to attack yellow moths first in low light conditions, whereas white moths were attacked first more frequently in bright light conditions. Our results show that light environments affect predator foraging decisions, which may facilitate context-dependent selection on visual signals and diversity of prey phenotypes in the wild. Light environments are constantly changing and may alter visual appearance of prey, but also bias predators' decision making. Our findings using blue tits in visual search tasks and the wood tiger moth prey under two light environments demonstrate that birds show context-dependent predatory behavior. This suggests that light environments can play a major selective role and influence visual signaling in the wild.
  • Tammilehto, Jaakko; Bosmans, Guy; Kuppens, Peter; Flykt, Marjo; Peltonen, Kirsi; Kerns, Kathryn A.; Lindblom, Jallu (2022)
    Attachment theory proposes that the activation of the attachment system enacts emotion regulation (ER) to maintain security or cope with insecurity. However, the effects of ER on attachment states and their bidirectional influences remain poorly understood. In this ecological momentary assessment study, we examined the dynamics between attachment and ER. We hypothesised that attachment states and ER influence each other through time. Specifically, we hypothesised bidirectional short-term cycles between state attachment security and reappraisal, state attachment anxiety and rumination, and state attachment avoidance and suppression. We also tested how trait attachment is related to state attachment and ER. One hundred twenty-two participants (M-age = 26.4) completed the Experiences in Close Relationship-Revised and reported state attachment and ER seven times daily for seven days. The results were only partly consistent with our cycle hypotheses yet revealed a cycle between low state attachment security and rumination that was attenuated by reappraisal. Moreover, rumination and suppression predicted increased insecure states, and reappraisal predicted increased secure and insecure states. Finally, trait attachment showed associations with state attachment and ER. Our study suggests regulatory dynamics between attachment and ER and opens important questions about their functional relationship in maintaining attachment-related behavioural patterns and emotional well-being.
  • Kuukka-Anttila, Hanna; Peuhkuri, Nina; Kolari, Irma; Kause, Antti (2020)
    Parasite infectivity, virulence and host resistance have been in the centre of the scientific interest when it comes to host-parasite relationships. In addition to resistance, hosts may also vary in their tolerance against parasites. This is important to notice because resistance and tolerance have different consequences in host-parasite co-evolution. Here, we show that families of farmed rainbow trout (Oncorhynchus mykiss) show both host defence strategies, resistance, and tolerance, against infectivity and virulence ofDiplostomumsp. (Trematoda) parasites. Both strategies have moderate genetic variation and are genetically independent of each other. It is also shown that the families having the highest performance measured as higher weight, better condition factor and lower mortality in absence of the parasites suffer the most when parasitism increases. For practical breeding programmes, this means that both resistance and tolerance can be improved by selection without compromising one of the strategies. These results give new insight into defence strategies against parasites in fish and into processes of fish-parasite co-evolution.
  • Penteriani, Vincenzo; Delgado, Maria del Mar; Campioni, Letizia; Lourenço , Rui (2010)
  • Winters, Anne E.; Lommi, Jenna; Kirvesoja, Jimi; Nokelainen, Ossi; Mappes, Johanna (2021)
    Aposematic organisms warn predators of their unprofitability using a combination of defenses, including visual warning signals, startling sounds, noxious odors, or aversive tastes. Using multiple lines of defense can help prey avoid predators by stimulating multiple senses and/or by acting at different stages of predation. We tested the efficacy of three lines of defense (color, smell, taste) during the predation sequence of aposematic wood tiger moths (Arctia plantaginis) using blue tit (Cyanistes caeruleus) predators. Moths with two hindwing phenotypes (genotypes: WW/Wy = white, yy = yellow) were manipulated to have defense fluid with aversive smell (methoxypyrazines), body tissues with aversive taste (pyrrolizidine alkaloids) or both. In early predation stages, moth color and smell had additive effects on bird approach latency and dropping the prey, with the strongest effect for moths of the white morph with defense fluids. Pyrrolizidine alkaloid sequestration was detrimental in early attack stages, suggesting a trade-off between pyrrolizidine alkaloid sequestration and investment in other defenses. In addition, pyrrolizidine alkaloid taste alone did not deter bird predators. Birds could only effectively discriminate toxic moths from non-toxic moths when neck fluids containing methoxypyrazines were present, at which point they abandoned attack at the consumption stage. As a result, moths of the white morph with an aversive methoxypyrazine smell and moths in the treatment with both chemical defenses had the greatest chance of survival. We suggest that methoxypyrazines act as context setting signals for warning colors and as attention alerting or "go-slow" signals for distasteful toxins, thereby mediating the relationship between warning signal and toxicity. Furthermore, we found that moths that were heterozygous for hindwing coloration had more effective defense fluids compared to other genotypes in terms of delaying approach and reducing the latency to drop the moth, suggesting a genetic link between coloration and defense that could help to explain the color polymorphism. Conclusively, these results indicate that color, smell, and taste constitute a multimodal warning signal that impedes predator attack and improves prey survival. This work highlights the importance of understanding the separate roles of color, smell and taste through the predation sequence and also within-species variation in chemical defenses.
  • Eskelinen, Teppo; Ylonen, Matti (2017)
    Tax havens and tax flight have lately received increasing attention, while interest toward multilateral trade policies has somewhat diminished. We argue that more attention needs to be paid exactly to the interrelations between trade and tax policies. Drawing from two case studies on Panama's trade disputes, we show how World Trade Organization (WTO) rules can be used both to resist attempts to sanction secrecy structures and to promote measures against tax flight. The theory of new constitutionalism can help to explain how trade treaties can 'lock in' tax policies. However, our case studies show that trade policy not only 'locks in' democratic policy-making, but also enables tax havens to use their commercialized sovereignty to resists anti-secrecy measures. What is being 'locked in' are the policy tools, not necessarily the policies. The changing relationship between trade and tax policies can also create new and unexpected tools for tackling tax evasion, underlining the importance of epistemic arbitrage in the context of new constitutionalism. In principle, political actors with sufficient technical and juridical knowledge can shape global tax governance to various directions regardless of their formal position in the world political hierarchies. This should be taken into account when trade treaties are being negotiated or revised.
  • Valkonen, Janne K.; Vakkila, Annu; Pesari, Susanna; Tuominen, Laura; Mappes, Johanna (2020)
    Antipredator adaptations in the form of animal coloration are common and often multifunctional. European vipers (genus Vipera) have a characteristic dorsal zigzag pattern, which has been shown to serve as a warning signal to potential predators. At the same time, it has been suggested to decrease detection risk, and to cause a motion dazzle or flicker-fusion effect during movement. We tested these hypotheses by asking whether (1) the zigzag pattern decreases detection risk and (2) the detection is dependent on the base coloration (grey or brown) or the snake's posture (coiled, basking form or S-shaped, active form). Additionally, (3) we measured the fleeing speed of adders, Vipera berus, and calculated the flicker rate of the zigzag pattern, to see whether it is fast enough to cause a flicker-fusion effect against predators. Our results show that the zigzag pattern reduced detectability regardless of base coloration or posture of the snake. The brown zigzag morph was detected less often than the grey zigzag morph. The fleeing speed of adders appeared to be fast enough to induce a flicker-fusion effect for mammalian predators. However, it is unlikely to be fast enough to induce the flicker-fusion effect for raptors. Our findings highlight that the colour pattern of animals can be multifunctional. The same colour pattern that can decrease detection by predators can also serve as a warning function once detected, and potentially hinder capture during an attack. (c) 2020 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.
  • Linke, Daniel; Elias, Marianne; Kleckova, Irena; Mappes, Johanna; Matos-Maravi, Pavel (2022)
    Advertising escape ability could reduce predatory attacks. However, the effectiveness of certain phenotypic cues (e.g., color, shape, and size) in signaling evasiveness is still unknown. Understanding the role of such signals in driving predator learning is important to infer the evolutionary mechanisms leading to convergent evasiveness signals among prey species (i.e., evasive mimicry). We aim to understand the role of the color pattern (white patches on dark background) and morphology (extended butterfly hindwings) in driving learning and avoidance of escaping prey by surrogate avian predators, the European blue tit. These cues are common in butterflies and have been suspected to advertise escape ability in nature. We use dummy butterflies harboring shape and color patterns commonly found in skippers (family Hesperiidae). The prey models displayed the studied phenotypical cues (hindwing tails and white bands) in factorial combinations, and we tested whether those cues were learned as evasive signals and were generalised to different phenotypes. Our results suggest that hindwing tails and white bands can be associated with prey evasiveness. In addition, wild blue tits might learn and avoid attacking prey models bearing the studied phenotypic cues. Although blue tits seem to have an initial preference for the phenotype consisting of white patches and hindwing tails, the probability of attacking it was substantially reduced once the cues were associated with escaping ability. This suggests that the same morphological cues might be interchangeable as preference/avoidance signals. Further investigation of the salience of hindwing tails vs. white bands as cues for escaping ability, revealed that predators can associate both color pattern and shape to the difficulty of capture, and possibly generalize their aversion to other prey harboring those cues. More studies with larger sample sizes are needed to confirm this trend. Altogether, our results highlight the hitherto overlooked role of shape (butterfly hindwing tails) for signaling prey unprofitability.
  • Hamalainen, Liisa; Mappes, Johanna; Rowlane, Hannah M.; Thorogood, Rose (2019)
    Aposematism is an effective antipredator strategy. However, the initial evolution and maintenance of aposematism are paradoxical because conspicuous prey are vulnerable to attack by naive predators. Consequently, the evolution of aposematic signal mimicry is also difficult to explain. The cost of conspicuousness can be reduced if predators learn about novel aposematic prey by observing another predator's response to that same prey. On the other hand, observing positive foraging events might also inform predators about the presence of undefended mimics, accelerating predation on both mimics and their defended models. It is currently unknown, however, how personal and social information combines to affect the fitness of aposematic prey. For example, does social information become more useful when predators have already ingested toxins and need to minimize further consumption? We investigated how toxin load influences great tits' (Parus major) likelihood to use social information about novel aposematic prey, and how it alters predation risk for undefended mimics. Birds were first provided with mealworms injected with bitter-tasting chloroquine (or a water-injected control), before information about a novel unpalatable prey phenotype was provided via video playback (either prey alone, or of a great tit tasting the noxious prey). An experimentally increased toxin load made great tits warier to attack prey, but only if they lacked social information about unpalatable prey. Socially educated birds consumed fewer aposematic prey relative to a cryptic phenotype, regardless of toxin load. In contrast, after personally experiencing aposematic prey, birds ignored social information about palatable mimics and were hesitant to sample them. Our results suggest that social information use by predators could be a powerful force in facilitating the evolution of aposematism as it reduces predation pressure on aposematic prey, regardless of a predator's toxin load. Nevertheless, observing foraging events of others is unlikely to alter frequency-dependent dynamics among models and mimics, although this may depend on predators having recent personal experience of the model's unpalatability. A plain language summary is available for this article.
  • Hämäläinen, Liisa; Hoppitt, William; Rowland, Hannah M.; Mappes, Johanna; Fulford, Anthony J.; Sosa, Sebastian; Thorogood, Rose (2021)
    Social transmission of information is taxonomically widespread and could have profound effects on the ecological and evolutionary dynamics of animal communities. Demonstrating this in the wild, however, has been challenging. Here we show by field experiment that social transmission among predators can shape how selection acts on prey defences. Using artificial prey and a novel approach in statistical analyses of social networks, we find that blue tit (Cyanistes caeruleus) and great tit (Parus major) predators learn about prey defences by watching others. This shifts population preferences rapidly to match changes in prey profitability, and reduces predation pressure from naive predators. Our results may help resolve how costly prey defences are maintained despite influxes of naive juvenile predators, and suggest that accounting for social transmission is essential if we are to understand coevolutionary processes. Many species learn through social transmission, which can alter co-evolutionary selection pressures. Experiments involving artificial prey and social networks show that wild birds can learn about unpalatable food by watching others, which helps explain the persistence of costly prey defences despite influxes of naive juvenile predators.