Mouse-like rodents often take cover in natural shelters or burrow underground where they build simple nests. A few species build extensive shelters above ground, called lodges, mounds or houses. Here, we present the first phylogenetically controlled comparative study on the ecological factors of habitat heterogeneity, environmental aridity and fire risk related to nesting habits in mouse-like rodents (Myomorpha, 326 genera). Twenty species from seven genera were found to build lodges, and they mainly occur in arid environments with low fire risk. Most lodge-building species (14 out of 20) belong to the pack rats (genus Neotoma), which in phylogeny only represent one event of evolution of lodge building and therefore limit the statistical power of the phylogenetically controlled analysis. The Bayesian phylogenetic mixed-effects models show a phylogenetic signal of 0.43 for 515 Myomorpha species. Under this moderate to strong phylogenetic relatedness, we did not find specific factors being associated to the evolution of sheltering habit in Myomorpha. We suggest studying the importance of aridity combined with low fire risk for lodge building on the species level, for example, by studying the limits of species distribution ranges depending on these factors.
Carcass scavenging by vertebrates is a critical ecosystem service that is influenced by environmental factors such as season and habitat. However, there is limited understanding of the role that these factors play in shaping scavenging patterns across different bioregions. We used camera traps to monitor vertebrate scavengers at 120 kangaroo (Family: Macropodidae) carcasses that were positioned across different seasons (warm/cool) and habitats (open/closed canopy) in three disparate desert, subalpine and temperate bioregions in Australia. Our survey identified 27 species that scavenged carcasses and revealed clear differences in scavenging patterns across the three bioregions. Carcass use was highest for feral cats, birds of prey, corvids and red foxes in the desert bioregion; for reptiles and dingoes in the temperate bioregion and for feral pigs, possums and dingoes in the subalpine bioregion. Bioregional differences in scavenger guild composition explained >4.6 times more variation in scavenger guild dissimilarity than season and >9.8 times more variation than habitat. Further, habitat had few effects on scavenger communities or carcass detection and use, whereas season was a strong predictor of these responses. Across bioregions, there were some general seasonal and habitat scavenging trends, with mammals and birds often using carcasses more frequently in cooler seasons and birds detecting carcasses faster in open habitat. However, there was also extensive within-bioregion seasonal variation. For example, depending on bioregion, some animals scavenged more frequently or detected carcasses faster in warmer seasons (i.e. birds and reptiles). Our results show that vertebrate scavenging is mediated by a complex interplay of environmental variables, especially seasonality, which may operate differently across bioregions. These findings have implications for understanding variability in vertebrate scavenging patterns and, in turn, functionally redundant or complementary scavenging processes.
Under an optimal foraging scenario, prey selection would be expected to occur when food resources are abundant. A positive frequency-dependent prey selection would elicit prey switching when the abundance of main food resources decreases, potentially favouring community resilience to the effects of intensive, selective predation on a single prey. We assessed whether a positive frequency-dependent prey selection by the wolf Canis lupus occurred in two areas hosting abundant populations of wild ungulates, one in northern (Słowiński National Park, Poland) and the other one in southern (Maremma Regional Park, Italy) Europe, throughout a cold semester. In Słowiński, ungulate community was dominated by red deer Cervus elaphus (57% availability) over wild boar Sus scrofa (35%) and roe deer Capreolus capreolus (8%); wild boar and fallow deer Dama dama (43–37%) were more abundant than roe deer (20%) in Maremma. In both areas, wolf diet was dominated by wild ungulates, with a major use of red deer in Słowiński and wild boar in Maremma. Prey selection occurred in both areas, and it was addressed towards the most abundant prey in Słowiński, that is, the red deer, but only towards the wild boar in Maremma, where the fallow deer was used according to availability. In Slowinski, high red deer density may have driven wolf prey selection, while the shifting of activity rhythms of the fallow deer in the Maremma as antipredator response to wolf presence may have reduced predation. Despite its comparable densities between the two areas, the wild boar was selected in Maremma and under-used in Słowiński. Results provide partial support to positive frequency-dependent selection, emphasising the spatiotemporal plasticity of wolf–prey relationships. The relative role of prey density and other factors (e.g., antipredator behavioural responses) should be assessed at longer temporal scales.
Understanding how species respond to environmental changes, particularly in the context of climate change, is crucial for biodiversity conservation. This study focuses on the plastic responses of canyon tree frog (Dryophytes arenicolor) larvae to variations in temperature and pond-drying, examining potential consequences of climate change. Frog larvae serve as an excellent model due to their high responsiveness to environmental cues during development. We analysed the impact of temperature and pond-drying on morphological and life-history traits, via a common garden experiment with individuals from three distinct populations with different ecological conditions. The experiments revealed significant differences in responses among populations, indicating geographic variation in plasticity. Pond-drying treatments led to reduced survival and reduction of morphological traits and growth, challenging the assumption that tadpoles have adaptive responses to drying conditions. In contrast, temperature treatments showed variable effects, with elevated temperatures generally favouring growth rates, reducing metamorphosis time, and having population-specific morphological shifts. We emphasize the importance of considering both morphological and life-history traits, as well as geographic variation, in assessing species' vulnerability to climate change. Furthermore, the integration of environmental standardized plasticity index (ESPI) and relative distances plasticity index (RDPI) in amphibian developmental plasticity will allow to quantify and compare plastic responses among populations and even other amphibian species in which these metrics are obtained in the future. Our results underscore the complexity of phenotypic plasticity, revealing genotype–environment interactions. These findings contribute valuable insights into the potential adaptability of D. arenicolor populations to ongoing climate changes, highlighting the need for comprehensive inter-population studies for a more nuanced understanding of species' responses to environmental change, and suggest that certain populations may be more vulnerable to extinction or better equipped to handle climate change based on their ability to adapt to environmental change.