Volume 106, Issue 2, April 2025

We compared the diet of 3 common species of frugivorous bats using identification of seeds found in feces versus the 18S rDNA V9 metabarcoding. Using metabarcoding we identified 20 plant species versus 10 species with taxonomic identification of seeds. Metabarcoding made it possible to detect more interactions and a greater percentage of samples to the species level. Fifty percent of the plant species (8 species) recorded in the diet of Sturnira hondurensis, 62% (8 species) for Carollia perspicillata, and 50% (4 species) for Artibeus lituratus were exclusively detected with metabarcoding. The incorporation of molecular biology to determine the diet of frugivorous bats made it possible to suggest that it is more diverse than previously known.

Food is one important way in which animals manage water. However, food varies in both composition and seasonal availability, forcing animals to make decisions that could have a substantial effect on their survival. To understand ways in which the desert-adapted Cactus Mouse, Peromyscus eremicus, responds to variation in dietary fat content, mice were fed to 1 of 2 diets: a higher fat diet or a lower fat diet. Mice fed the lower fat diet had higher rates of water loss and differences in serum electrolyte values indicating dehydration. In environments where water scarcity is extreme, even small differences in water balance could have substantial effects on survival and reproductive success.

In the socially monogamous prairie vole, we found strong evidence that genetic similarity between males and females that produced offspring via extra-pair copulation (EPC) was less than that between social partners. This finding supports the hypothesis that EPC could be a mechanism to reduce inbreeding depression.

Dispersal in golden-mantled ground squirrels occurs mostly during the summer of birth and is male-biased. The dispersal decision for females originates soon after emergence from the natal burrow, and the females with littermate sisters present are more likely to disperse.

Eastern gray squirrels and fox squirrels may use niche partitioning to avoid competition. We found no evidence for temporal partitioning but found that different environmental characteristics affected occupancy of each species and co-occurrence was influenced by distance to road.

We quantified changes in small mammal abundance across an urban intensity gradient in the Midwestern United States. Prairie-associated species were more abundant in tall vegetation bordering mowed parks while habitat generalists were more abundant on sites with greater canopy and shrub cover.

Urbanization represents the greatest threat to habitat degradation. In agreement with this, in a subtropical area of northern Argentina, we found a negative association between urbanization and small rodent diversity, evidenced by a reduction in the number of native species in the most urbanized areas.

We explored the theft, or pilferage, risk of seeds buried and exposed to mammalian hoarders. Although most of our buried seeds were stolen before the end of the hoarding season, we found evidence that animals can selectively pilfer preferred seeds, highlighting the importance of pilferage reduction strategies.

Daurian Pika presence decreased strongly in areas with shorter grass height and fewer forbs, and their abundance declined in areas of heavy grazing and high soil moisture. Results highlight the strong declines that high grazing pressure can have on this species.

Antipredator behavior should increase fitness of animals but bats present mixed signals. Bat emergence was delayed while under simulated threat but was overpowered by responses to weather. While foraging within owl territories bats decreased their activity while under any treatment.

In the United States, Eastern Fox Squirrel populations are highly genetically similar across its native and introduced ranges. This pattern indicates that this species experienced rapid population growth and range expansion since the end of the last ice age (~12,000 years ago).

The Great Basin is a massive region of western North America, named for being a place where most rivers drain inward and disappear. Genetic data reveal a new species of ground squirrel endemic to Idaho, at the Basin’s far northern rim, highlighting the overlooked mammal diversity of this geographically unique region.

We used mitochondrial DNA sequences and microsatellite loci to examine mating patterns in the socially monogamous Desert Kit Fox and compared levels of genetic variation across other canids. Our results indicated evidence of extra-pair mating, resulting in mixed paternity litters, and supported male-biased dispersal. Additionally, we sequenced dog-specific microsatellite markers used extensively in other studies and identified loci that differed from the original dog repeat motif.

We used genome sequencing, population genetic, and phylogenetic techniques to identify pocket gopher subspecific boundaries in Texas. Using these methods, we determined the number of OTUs in each genus to be 5 for Thomomys bottae, 8 for Geomys species, and 5 for Cratogeomys castanops.

Determining genetic relationships is challenging when speciation happens rapidly. We used phylogenetic methods that work well under rapid diversification to resolve the position of Pipistrellus nathusii and corroborate earlier work supporting generic status for Asian pipistrelles.

Our findings suggest that warmer temperatures in southern hibernacula may provide optimal conditions for growth of Pseudogymnoascus destructans (Pd), the fungus that causes white-nose syndrome. Should Pd reach the southernmost hibernacula, research will be needed to determine whether white-nose syndrome develops and how lethal it will be.

This study explored regional, seasonal, and historical dietary change in black-backed jackals. Using dental microwear texture analysis, significant differences were found in East African populations over time, highlighting dietary flexibility as a response to anthropogenic impacts.

Study on young harbor seals reveals that body measurements such as body and teeth length can accurately estimate their age, aiding in conservation and rehabilitation efforts. Captive-raised pups grow differently from those in the wild, and initial poor body condition persists during rehabilitation.

Why do females maintain an active corpus luteum if they are not pregnant, and why does this phenomenon vary across species? A new comparative evolutionary study across 72 species discovers one potential answer: corpora lutea lifespan in nonpregnant females is positively correlated with gestation length. Active corpora lutea in nonpregnant females may represent physiological inertia leftover from preparing for implantation and pregnancy.

Pantanal Wetland feral hogs have coexisted with indigenous mammal species for about 175 years in Central Brazil. In the last 20 years, European wild boars were introduced in this region as game species and started to breed with these feral hogs leading to unpredictable morphological and ecological alterations.

Here, we present best practices for the required elements of a taxonomic description and identify some of the common pitfalls leading to an inadequate description resulting in an unavailable name. We also suggest best practices that would enhance taxonomic descriptions and make them more informative.