Human evaluation of amphibian species: a comparison of disgust and beauty

Bioecological representations and social characteristics of students influence their attitudes toward wild vertebrates

BACKGROUND

The origin of different human emotions directed towards animals (whether in the utilitarian, affective, conflictual, or cosmological context) is strongly influenced by sociocultural factors, although our genetic predispositions also play an important role in the origin of these emotions. Such emotions guide people's representations of different species, which in turn affect their attitudes toward them. For this reason, understanding the factors that guide such attitudes becomes a key element in making conservationist decisions. In this sense, the main objective of this study was to analyze how sociocultural characteristics and bioecological representations can influence students' attitudes of empathy or antipathy towards vertebrate species; as well as which classes and species are related to greater and lesser support in people for their conservation.

METHODS

To do so, 667 interviews were conducted with students from urban (n = 1) and rural (n = 2) schools in the Brazilian semi-arid region. We used mixed generalized linear models (GLMM) to examine the effect of social factors and bioecological representations on empathy and antipathy attitudes and multiple factor analysis (MFA) to examine the relationship between the biological characteristics of the animals (positive or negative) and the attitudes toward them (antipathetic or empathetic).

RESULTS

Through GLMM, we found that students from the urban area and from lower school levels are more extreme in their responses, more frequently expressing both empathy and antipathy towards wild animals. Regarding gender, women had a higher frequency of responses associated with aversion than men for species perceived as dangerous and poisonous (p < 0.001). Through the MFA, we found greater support (empathy) for the conservation of fish species (31.56%), birds (29.37%) and mammals (25.94%), with emphasis on the Red-cowled cardinal (Paroaria dominicana) and clownfish (Amphiprion ocellaris) species, and less support (antipathy) for reptile and amphibian species such as rattlesnakes (Crotalus durissus) and horned frogs (Ceratophrys joazeirensis).

CONCLUSIONS

The attitudinal ambivalence reflected by varying empathy for certain species and antipathy to others has important implications for wildlife conservation. Understanding the socioeconomic factors and emotions that influence attitudes towards animals can enable integrating educational strategies for the conservation of species, especially those which are culturally important.

Amphibian Skin and Skin Secretion: An Exotic Source of Bioactive Peptides and Its Application

Amphibians have been consumed as an alternative protein source all around the world due to their delicacy. The skin of edible amphibians, particularly frogs and giant salamanders, always goes to waste without further utilization. However, these wastes can be utilized to extract protein and bioactive peptides (BPs). Various BPs have been extracted and reported for numerous biological activities such as antioxidant, antimicrobial, anticancer, antidiabetic, etc. The main BPs identified were brevinins, bombesins, dermaseptins, esculentins, magainin, temporins, tigerinins, and salamandrins. This review provides a comprehensive discussion on various BPs isolated and identified from different amphibian skins or skin secretion and their biological activities. The general nutritional composition and production statues of amphibians were described. Additionally, multiple constraints against the utilization of amphibian skin and secretions are reported. Finally, the prospective applications of BPs in food and biomedical industries are presented such as multifunctional food additives and/or supplements as well as drug delivery agents.

Factors Influencing the Sponsoring of Animals in Slovak Zoos

Simple Summary

To achieve conservation goals with ex situ programs, zoos have two alternatives: government funding and private donations. By using published data from 2018 on the amount of money received by zoos through adoption programs (if any), we investigated the factors influencing donations in all Slovak zoos. Generalized linear mixed models were applied throughout statistical analyses. Although the majority of animal species in the zoos included in this study had low a conservation status, a few others, like amphibians, were rarely listed as threatened species. In general, vertebrates received more funding than invertebrates, and mammals were the preferred taxa by private contributors. Mammals were sponsored more frequently than non-mammal species, except for reptiles. We submit that zoo managers could concentrate their efforts on the breeding of threatened animals to support their reintroduction to the wild and to enhance people’s awareness of these animal species.

Abstract

Anthropogenic disturbance causes biodiversity loss, and consequently the captive conservation (ex situ) of threatened animals may be an effective strategy in protecting species. We used estimated body mass, phylogenetic closeness with humans, International Union for Conservation of Nature (IUCN) conservation status, and species attractiveness scores, to examine the factors influencing the adoption likelihood of a species in all Slovak zoos. In general, vertebrates received more funding than invertebrates, and mammals were the preferred taxa by private contributors. In terms of funding, we propose that the perception of mammals as phylogenetically close to humans, and attractiveness factor, contribute to an advantage over less attractive and phylogenetically distant species. Conservation status also contributed to the amount of donations; however, the magnitude of these relationships was weak when compared to the effect of animal taxa. These results suggest that Slovak zoos might be more successful in raising donations by breeding threatened species, and raising public awareness about these animal species. Displaying popular, flagship species of non-mammal taxa may increase interest among the public as well, and may translate into a significant growth in the amount of donations.

What Makes Spiders Frightening and Disgusting to People?

The quality of human-animal interactions may crucially influence conservation efforts. Unfortunately, and despite their important roles in the functioning of the ecosystem, some animals are considered notoriously unpopular. Using the forced-choice paradigm, we investigated which cues humans perceive as frightening and disgusting in spiders, one of the most unpleasant animals in the world. The research was carried out with a representative sample of N = 1,015 Slovak adults. We found that perceived fear and disgust of spiders were triggered predominantly by enlarged chelicerae, enlarged abdomen, and the presence of body hair. Longer legs were associated with perceived fear as well; however, the presence of two eyes did not produce any statistical significance in terms of fear. We hope that further research in this field, where additional cues can be manipulated (e.g., color and number of legs), will improve conservation efforts by using an improved reputation of spiders in the eyes of the general public.

The Ultimate List of the Most Frightening and Disgusting Animals: Negative Emotions Elicited by Animals in Central European Respondents

Animals have always played an important role in our everyday life. They are given more attention than inanimate objects, which have been adaptive during the evolution of mankind, with some animal species still presenting a real threat to us. In this study, we focused on the species usually evaluated as the scariest and most disgusting in the animal kingdom. We analyzed which characteristics (e.g., weight, potential threat for humans) influence their evaluation in a nonclinical Central European WEIRD population (Western, educated, industrialized, rich, and democratic). The tested animals were divided into two separated sets containing 34 standardized photos evoking predominantly one negative emotion, fear or disgust. The pictures were ranked according to their emotional intensity by 160 adult respondents with high inter-rater agreement. The most fear-eliciting species are mostly large vertebrates (e.g., carnivorans, ungulates, sharks, crocodiles), whereas smaller fear-evoking vertebrates are represented by snakes and invertebrates are represented by arachnids. The most disgust-evoking animals are human endo- and ectoparasites or animals visually resembling them. Humans emotionally react to fear-evoking animals that represent a real threat; however, identifying truly dangerous disgust-evoking animals might be harder. The results also support a somewhat special position of snakes and spiders.

Venomous snakes elicit stronger fear than nonvenomous ones: Psychophysiological response to snake images

Snakes have been important ambush predators of both primates and human hunter-gatherers throughout their co-evolutionary history. Viperid snakes in particular are responsible for most fatal venomous snakebites worldwide and thus represent a strong selective pressure. They elicit intense fear in humans and are easily recognizable thanks to their distinctive morphotype. In this study, we measured skin resistance (SR) and heart rate (HR) in human subjects exposed to snake pictures eliciting either high fear (10 venomous viperid species) or disgust (10 nonvenomous fossorial species). Venomous snakes subjectively evaluated as frightening trigger a stronger physiological response (higher SR amplitude) than repulsive non-venomous snakes. However, stimuli presented in a block (more intense stimulation) do not trigger a stronger emotional response compared to sequentially presented stimuli (less intense stimulation). There are significant interindividual differences as subjects with high fear of snakes confronted with images of viperid snakes show stronger, longer-lasting, and more frequent changes in SR and higher HR compared to low-fear subjects. Thus, we show that humans demonstrate a remarkable ability to discriminate between dangerous viperids and harmless fossorial snakes, which is also reflected in distinct autonomous body responses.