Not all animal species, whether endangered or not, are fortunate enough to be appreciated by humans. While it is true that aesthetic reasons are not (or should not be) scientifically accepted when carrying out conservation measures, the fact remains that aesthetics greatly influences the support given by the public and various decision-making bodies to the preservation of many species . It is easier to justify the preservation of more aesthetically pleasant species than less appreciated species . Considering this, species like the giant panda (Ailuropoda melanoleuca) and dolphins are often used as symbols by famous organizations or environmental protection agencies and are called "flagship species". They are ambassadors for conservation and their protection contributes to the preservation of other organisms in their ecosystems [3, 4]. Human preferences among different types of organisms have influenced the provision of conservation resources toward large charismatic species  and what are largely considered by the public to be more attractive vertebrate groups . Birds, mammals, and fishes may have been more privileged and protected because they are more socially accepted than reptiles, amphibians, and invertebrates ; however, there are exceptions . For example, bats are also mammals, but they are regarded as similar to reptiles or invertebrates. The Iberian wolf (Canis lupus signatus) is another exception to this rule and illustrates the factors affecting wildlife conservation. In Portugal the wolf's image (e.g., as a bloodthirsty, demonic, man-eating animal) has been influenced by negative values, folklore, and mythologies and it has been perceived as a threat to regional pastoralist economies . Fear and competition for food create a conflict between the wolf and man, leading to persecution and deliberate extermination of wolves . The perception that a particular animal is dangerous and aggressive to humans, like the Iberian wolf in Portugal, has led to other similar situations for other large carnivores all over the world, as documented in other studies [10–20].
Although reptiles and amphibians are not responsible for major economic losses and most are harmless, they are feared and persecuted [21, 22]. In fact, many reptiles are quite useful for human beings, not only as sources of food , medicines , and raw materials , but also in terms of ecological equilibrium. Despite this usefulness to human beings, many animals are seen as dangerous and are persecuted. For instance, despite its ecological importance and role in preventing mosquito plagues, the gecko is seen as a poisonous and evil animal and is therefore persecuted in Portugal . Knight  showed that most people disdain creatures that represent little threat to humans. These fears are often irrational and might be connected to animal phobias , cultural issues [12, 25], and emotional reactions . Aspects of human evolution might also have led to fears of these animals. Sagan  suggests that the human fear of reptiles could be a result of the ancient conditions in which the first mammals evolved. In addition to that, he suggests that these fears may even be an evolutionary heritage. The high prevalence of fear of snakes and other animals among humans and other primates suggests that this fear is the result of an ancient evolutionary history, and genetic variability may explain why not all individuals harbor these phobias [27, 28].
Morris and Morris  reported that in Britain 27% of the children interviewed stated that snakes were the least liked animal and that 24% of people said that snakes were the animals whose conservation status they cared about least. Agras et al.  reported that in a U.S. study, fear of snakes was the most intense compared with other animal phobias in the country, and this fear was prevalent in 38% of women and 12% of men interviewed. Fear of certain animals constitutes a great number of phobias, such as fear of spiders (arachnophobia), insects (insectophobia), rats (musophobia), and snakes (ophidiophobia), with snakes being at the top of the list globally . Phobias associated with snakes and spiders are the most common phobias in Western societies and may result in part from genetic predisposition associated with the risk experienced by humans during their evolution, resulting in a process known as biophobia . These types of feelings towards animals are what Kellert [14, 25, 33] defines as negative values in his typology of attitudes towards animals.
The causes of human persecution of animals have various natures [17, 19, 20, 24, 34], and the existence of a large number of myths, stories, and misconceptions (some of them resulting from the direct interpretation of local folklore) may be largely responsible for some of this persecution [19, 22]. In Portugal, there are a large number of such folklore tales about reptiles and amphibians [22, 24, 35, 36], mostly depicting reptiles and amphibians as evil and dangerous animals. These types of misconceptions are just more ideas to add to the vast list of erroneous ideas and negative values about reptiles and amphibians. The idea of threat or potential harm to humans is one of the main reasons for disliking animals, and the prevalence of perceptions rather than actual bio-ecological characteristics is also the most important reason for the preference for certain types of animals.
All of those folklore, ideas, perceptions, and values are a very important part of the human relation with animals (besides the more "scientific" zoological approaches) and can be considered as a part of the human relation with animals, or "ethnozoology". According to Alves et al.  we can define ethnozoology as "the variety of interactions (both past and present) that human cultures maintain with animals" and this type of study "has its roots as deep within the past as the first relationships between humans and other animals". Although dealing with a very vast and important area--all the types of human relations with animals--these studies are still not very common worldwide, except in Brazil , where many studies have already been done. In this regard, as a sub-part of ethnozoology, ethnoherpetological studies are even less common worldwide. Ethnoherpetology can be defined as the study of people's relations with and knowledge about reptiles and amphibians. Worldwide there are few studies on the topic, and existing ones are mainly concentrated in Africa [38–40], south America [41–45], and Asia [46–49]. In Europe these types of studies are very rare [50–52] and in Portugal, apart from some anecdotal references in some herpetological publications or in old general ethnographic studies, there are also few studies on the topic [24, 35, 36]. Studies presenting situations in which this type of knowledge has a negative impact on conservation are few, and almost none have ever established a clear link between the presence of folklore, negative values, and preferences and persecution and anti-conservation attitudes towards reptiles.
It is therefore extremely important to understand how common these tales, folklore, misperceptions, and negative values are in societies and how these factors can contribute to the persecution of reptiles and amphibians and affect their conservation. Although the theme is quite common and is reported as anecdotal information in the literature on herpetology, conservation biology, and ethnozoology [3, 4, 21, 22, 35], few studies have been dedicated to understanding how the presence of these topics may or may not influence peoples' attitudes towards reptiles and amphibians. This work is intended to be an early contribution to clarify the situation. Thus, the general objectives of this study were to analyze human values and folklore about herpetofauna and their possible relationship with the persecution which this fauna suffers.