The indication of mammals and birds as the most studied animals in the schooling processes experienced, as well as the most indicated as locally occurring, by the questioned students evidences a tendency of greater human interest in these animal groups, which reinforces the results of other studies [22,23,24]. This tendency may reflect the greater phylogenetic proximity of these animals with humans, or utilitarian, aesthetic, or conflictual factors, among others [8, 22, 25,26,27,28,29,30]. These factors, reinforced by the students’ greater interest in and curiosity about these animal groups, may influence their approach to formal education processes. In this sense, Lindemann-Matthies  noted that children, as well as adults, in all age groups at school are more interested in animals, especially large mammals.
For the other animal groups, the data revealed a tendency toward limited knowledge regarding diversity, with a predominance of citation frequencies being for generic terms such as “birds,” “reptiles,” “snakes,” “amphibians,” and “fish,” with no indication of the diversity that exists within each of these groups. This fact may reflect factors such as habitat and morphological aspects of these animals, but also, above all, little emphasis on the diversity of these animal groups in the education processes. Limitations in knowledge regarding the diversity of some animal groups have a significant impact on human alienation from animal conservation . Thus, knowledge is considered a priority condition for the development of positive behaviors and attitudes , without which conservation efforts are not viable . In the case of amphibians, for example, Tarrant et al.  highlighted that research with students in South Africa revealed that conceptual limitation with these animals is frequent, even among educators.
Mammals and birds were indicated as the most addressed local animals in the educational processes experienced. Among mammals, however, domestic animals (“dog” and “can”) were the most cited, followed by exotic animals (“lion,” “jaguar,” and “tiger”) and only one locally occurring animal (“fox”), which reflects a limited understanding of the local fauna. In addition to these, citations were also frequent for “ox/cow” (Order Artiodactyla) and “horse” (Order Perissodactyla). Among the birds mentioned, in addition to the domestic “chicken” (Order Galliformes), there was a predominance of birds that are the target of hunting or are involved in conflicts with local people, especially in the rural context. These results allow us to reiterate conclusions observed in previous studies, that in addition to the influence of phylogenetic proximity, human interest in animals rests on aesthetic and utilitarian factors, among others [8, 22, 25,26,27,28,29,30], reverberating, therefore, in the curricular approach practiced. In addition, our results, in part, are supported by curricular parameters for Brazilian basic education (Ensino Básico), which emphasize the relationship between the thematic blocks “Environment” and “Technological Resources,” the use of living beings as natural resources, examples of hunting and animal breeding, and problematic predatory initiatives, with a view to the development of conservationists [1, 2].
For the other animal groups indicated as the most studied by the research participants, there were limitations in their recognition of the diversity of animals cited, and thus of their ecological importance. This constraint limits the development of critical awareness in light of the importance of biodiversity conservation since, as pointed out by Orientações Curriculares Brasileiras (Brazilian Curriculum Guidelines) for basic education, knowledge of the diversity of life, as well as of aspects related to its conservation, must appear as fundamental aspects of education processes, from the perspective of developing critical awareness about relationships/interactions between humans and other life forms [1,2,3,4,5]. Among the objectives of biodiversity education, we highlight the relevance of broader diversification of known organisms, for which school education has an indispensable function .
In all of the situations analyzed, even when the approach was directed to vertebrates in the region under study, invertebrates were cited as animals studied in science/biology classes, despite the low richness of the citations when compared to other cited animal groups. The highest frequencies were for “insects,” “mosquitos” (Class Insecta), and “earthworm” (Phylum Annelida), reflecting, perhaps, greater contact between students and these animals, especially in the rural context. We also highlight, among other cited groups, a high citation frequency for “bacteria,” mostly by rural students. In all these cases, one may conclude, among other factors, that there is inattention and/or poor clarity about the distinction between “vertebrates,” “invertebrates,” and “unicellular beings.” Because it is an elementary aspect, and of utmost importance for subsequent learning with a view to the development of critical awareness in reading and understanding about life forms, it is worth reflecting on the role of schooling, especially biology education, in developing adequate recognition of animal categories. Converging with these considerations, the Orientações Curriculares Brasileiras for basic education emphasize the importance of knowing, from the initial grades of schooling, how to classify animals into groups, such as vertebrates and invertebrates, among others, with an emphasis on their ecological and evolutionary implications [1, 2]. Páramo and Galvis  emphasized that in some cases, children do not recognize animal categorizations. Reinforcing investments in early childhood education, therefore, are critical for appreciating wildlife in subsequent stages of schooling [22, 26, 31].
In practically all situations analyzed, the average number of citations of animals was higher at the end of Ensino Médio, which reflects, in our view, the cumulative effect of the curriculum experienced, contributing to the expansion of the repertoire of animals known by students. That is, according to the curricular guidelines for basic education in Brazil, the content about animals is expanded from one schooling cycle to another, aiming at the development of valorization of biodiversity and the preservation of environments. In other words, biological contents are repeatedly addressed in depth as the cycles of schooling advance [1, 2, 5], based on a cognitive-based curricular logic [32,33,34,35,36].
An approach emphasizing the importance of animal conservation was recognized in the educational processes experienced by the majority (almost 70%) of the students, which is an important finding. However, conceptual understanding of “Conservation of Nature” ranged from 31.21% for rural students in Ensino Fundamental II to 52.20% for urban students in Ensino Médio. This finding reflects, in a way, disagreement with Brazilian curriculum guidelines on the subject, which proposes that this topic should be approached, implicitly or explicitly, throughout all curricular practice in basic education [1,2,3,4,5], in addition to the more specific approach of it as a transverse (cross-cutting) theme “Environment,” in which the conceptual notion “Conservation of Nature” is explained as the use of natural resources in a “rational” way, seeking a good yield without exhausting capacity for “renewal” or its ability to be “self-sustaining”; and still adds, based on Brazilian law, “implies management, use with care and maintenance” [10, 11]. Such conceptual understanding has convergences with theoretical orientations of ecology [12,13,14,15,16]. Therefore, our results suggest the need for more theoretical investments in this conceptual understanding in formal educational processes, especially in the rural context where the aforementioned understanding is more critical. In short, efficiency in conceptual understanding of biodiversity and its conservation presupposes a rethinking of the curriculum from a more contextual, systemic, and interdisciplinary perspective [6, 9, 18].