Wildlife in Natural and Altered Environments: What Is Special About This Issue?

The interaction between humans and the environment often entails the deterioration of the latter triggered by the actions of the former [1]. Among the many consequences [2], alterations such as changes in the use of land [3], pollution [4], the global warming [5] and invasive species [6], as well as certain interactions among these factors [7,8,9], lead to environmental conditions that differ from those found in pristine habitats. This gives rise to particular ecological relationships [10] and, subsequently, evolutionary dynamics [11]. Under the topic “Wildlife in natural and altered environments,” this Special Issue seeks to examine the various consequences of such a habitat differentiation.

Separation of humans from nature often entails desensitization to environmental issues [12] that stems from physical and emotional detachment between the two [13]. In this Special Issue, we feature the work of Jürgens et al. [14], who studied how a person’s background—specifically their previous exposure to nature—largely determines their mental images of different animal species, in turn shaping both the nature and intensity of their reactions to encounters with wildlife. Aligning with this finding, Locquet and Simon’s work [15] confirmed that the preservation of nature requires a global territorial transition that reinforces the links between societies and nature in a way that is financially stable and ecologically sustainable. These pieces of research highlight the necessity of facilitating a reconnection between humans and nature [16] that promotes the social change needed to turn nature preservation into a priority [17].

The preservation of biodiversity requires meticulous knowledge of its spatial distribution [18], considering the relevance of a given species’ habitat for its conservation [19]. In this regard, Cruz-Bazan et al. [20] provide a thorough analysis of the intricate spatial–temporal patterns of mammal abundance in an extreme habitat, namely, the semi-arid regions of Mexico, whose ecological balance is extremely delicate [21]. Habitat selection depends, among other factors, on the availability of the resources used by the species in question [22], which can potentiate competition [23], thus limiting the ability of the species to prosper [24]. In this Special Issue, Kajita and Kajimura [25] demonstrate that dead culms of dwarf bamboo function as refuges for mice, although they do not preclude competitive exclusion between mice species. Also, these refuges favor more careful utilization and selection of more nutritious food sources, illustrating how a given resource can define the ecological relationships among species [25]. Furthermore, Twynham et al. [26] proved that habitat selection depends not only on the distribution of the resource in question but also on how a given species uses it. In their case, bears’ dietary specialization on ungulate neonates defines the extent to which the distribution of the latter determines that of the former [26]. In other cases, however, the scale and intent of distribution studies may have a different focus. Such is the case of the research by Bernotienė et al. [27], which centered on the vertical distribution of Culicoides midges—which can function as vectors for certain pathogens—in temperate forests. Their finding that these midges preferentially occupy the mid and high canopies of the forests they inhabit is of ecological interest but is also relevant from an epidemiological standpoint [27].

The distribution of animal species may change dramatically as a consequence of human alterations to the environment [28], often leading to fragmented populations whose continuity is subject to particular challenges [29]. In this context, Bišćan et al. [30] modeled the role of ecological corridors to ensure connectivity among isolated wolf populations in Croatia, where a strategy based on translocation of individuals along these corridors was predicted to be the most effective. Other consequences of human activities are related to global warming, which is reshaping the dynamics of numerous habitats [31]. In their study, Mullet and Farina [32] analyze the patterns of noise in the ecosystems resulting from the deicing of subarctic ecosystems in North America, where noise peaks in the vicinity of roads due to traffic and wind blocks the sounds animals produce to communicate. These acoustic patterns follow human rhythms and may pose a novel threat to animal communication in areas humans traditionally do not occupy [32]. Global warming can also lead to the proliferation of certain species [33], which can alter the use of space and others’ accessibility to resources [34]. This hypothesis was tested by Troppin and Valenzuela [35], who studied whether the overgrowth of floating vegetation affected the ability of females to produce vitamin D. Although these plants can block insolation on the surface of the water, turtles may use them as basking perches, a behavior that could explain why these turtles’ ability to produce vitamin D is not impaired by plant overgrowth [35]. In like manner, Zamora-Camacho [36] found a positive relationship between locomotor performance and parotoid gland size in toads, which did not differ between animals from agrosystems and natural habitats, again suggesting that certain phenomena are resilient to human alterations of the environment.

All in all, this Special Issue compiles evidence that human activities underlie the appearance of novel ecological interactions that, despite typically following deterioration of the environment, are worthy of analysis and reflection [37]. Accordingly, wildlife in both natural and altered habitats must be continuously assessed and compared, and the interactions and interfaces between them, which are not always easy to distinguish clearly, must be subject to particular attention [38]. Moreover, reversing, stopping, or ameliorating the consequences of global change often entails further alterations of the environment [39], which should be carefully planned [40]. Such planning requires a thorough analysis of these environments and the effects modifying them can trigger [41]. This Special Issue is a valuable contribution to these objectives.