The spatiotemporal context of individual specialization in resource use and environmental associations.

1. Individual niche specialization is widespread in natural populations and has key implications for higher levels of biological organization. This phenomenon, however, has been primarily quantified in resource niche axes, overlooking individual variation in environmental associations (i.

Trained quantity discrimination in invasive red-eared slider and a comparison with the native stripe-necked turtle.

Little is known about the behavioral and cognitive traits that best predict invasion success. Evidence is mounting that cognitive performance correlates with survival and fecundity, two pivotal factors for the successful establishment of invasive populations. We assessed the quantity discrimination ability of the globally invasive red-eared slider (Trachemys scripta elegans).

The role of a synanthropic bird in the nest niche expansion of a secondary cavity nester to man-made structures.

Species with similar ecological characters often compete with each other; however, a species may also facilitate the survival or reproduction of another ecologically similar species, although such interaction is rarely documented in birds. Here, we reported a facilitative species interaction between Asian house martins () and russet sparrows (), both passerines using closed nests, in a montane farming area of Taiwan. We found that Asian house martins constructed dome-shaped nests in human houses that provided additional nest sites for russet sparrows, secondary cavity nesters with greatly declining populations in Taiwan.

Niche overlap in rodents increases with competition but not ecological opportunity: A role of inter-individual difference.

Niche variation at population level mediates niche packing (i.e. patterns of species' spread within the niche space) and species coexistence at community level.

Morphological variations in a widely distributed Eastern Asian passerine cannot be consistently explained by ecogeographic rules.

Ecogeographic rules that describe quantitative relationships between morphologies and climate might help us predict how morphometrics of animals was shaped by local temperature or humidity. Although the ecogeographic rules had been widely tested in animals of Europe and North America, they had not been fully validated for species in regions that are less studied. Here, we investigate the morphometric variation of a widely distributed East Asian passerine, the vinous-throated parrotbill (), to test whether its morphological variation conforms to the prediction of Bergmann's rule, Allen's rules, and Gloger's rule.

Superior continuous quantity discrimination in a freshwater turtle.

Background: Quantity discrimination, the ability to discriminate a magnitude of difference or discrete numerical information, plays a key role in animal behavior. While quantitative ability has been well documented in fishes, birds, mammals, and even in previously unstudied invertebrates and amphibians, it is still poorly understood in reptiles and has never been tested in an aquatic turtle despite the fact that evidence is accumulating that reptiles possess cognitive skills and learning ability. To help address this deficiency in reptiles, we investigated the quantitative ability of an Asian freshwater turtle, Mauremys sinensis, using red cubes on a white background in a trained quantity discrimination task.

Niche-trait relationships at individual and population level in three co-occurring passerine species.

The niche variation hypothesis (NVH) predicts that populations with wider niches exhibit greater morphological variation through increased interindividual differences in both niche and morphology. In this study, we examined niche-trait relationships in three passerine species (, , and ). A total of 289 from 7 sites, 259 from 8 sites, and 144 from 6 sites were sampled along an elevation gradient (0-2,700 m) in Taiwan from 2009 to 2017.

Bigger doesn't mean bolder: behavioral variation of four wild rodent species to novelty and predation risk following a fast-slow continuum.

Background: Understanding how wild species respond to novel situations with associated risk can provide valuable insights for inter-specific behavioral variation and associations with pace-of-life (POL). Rodents, a globally distributed and diverse taxonomic group, have been the subjects of countless studies emulating risky situations. Controlled laboratory experiments with a focus on wild-caught species provide the opportunity to test fine-scale behavioral responses to contexts of risk with ecological implications.

Long-term monitoring reveals invariant clutch size and unequal reproductive costs between sexes in a subtropical lacertid lizard.

Based on 20,000 records representing . 11,000 individuals from an 8-year capture-mark-recapture (CMR) study, we tested and confirmed a new case of invariant clutch size (ICS) in a sexually dichromatic lacertid lizard, . In the grassland habitat of the early succession stage, females showed strictly low and invariant clutch size, multiple clutches in a breeding season, high reproductive potential, and annual breeding cycles that correspond to the emergence of male courtship coloration.

Spatial and temporal relationship between native mammals and free-roaming dogs in a protected area surrounded by a metropolis.

With rapid urbanization worldwide, anthropogenic impacts such as human settlements and invasive carnivores (dogs Canis familiaris, cats Felis catus) are altering spatial distributions and temporal activity patterns of native species. In this study, we focused on spatiotemporal responses of native mammals to anthropogenic impacts in a protected area surrounded by a large metropolis (i.e.

When males live longer: Resource-driven territorial behavior drives sex-specific survival in snakes.

Phylogenetic analysis has shown that males' propensity to engage in aggressive encounters is associated with females having greater longevity. Here, we confirm the causal link between aggression and reduced longevity by looking at an egg-eating snake () in which females defend territories in the presence of sea turtle eggs. We monitored aggressiveness and survival at two sites: a control site with a stable supply of turtle eggs, and a second site where we collected data before and after a storm that eroded the beach on which turtles nested, thus leading to a loss of territoriality.

Effects of Greenfall on Ground-dwelling Arthropods in a Subtropical Forest.

Resource events such as typhoon-triggered greenfall have consequences for multiple ecological mechanisms, ranging from population dynamics and trophic interactions to ecosystem processes. Arthropods are sensitive to environmental disturbances, and many taxa have been used as indicator species. In a field experiment, we tested the effects of greenfall on ground-dwelling arthropods (mostly litter-dwelling taxa) in a forest of Taiwan red pine () in the summer of 2013.

The effects of food and parasitism on reproductive performance of a wild rodent.

Food and parasitism can have complex effects on small mammal reproduction. In this study, we tested the effects of sex, food, and parasitism on reproductive performance of the Taiwan field mouse (). In a field experiment, we increased food availability for a portion of the mice in the population by providing sorghum seeds to a set of food stations.

Genomic Analysis of Demographic History and Ecological Niche Modeling in the Endangered Sumatran Rhinoceros Dicerorhinus sumatrensis.

The vertebrate extinction rate over the past century is approximately 22-100 times greater than background extinction rates [1], and large mammals are particularly at risk [2, 3]. Quaternary megafaunal extinctions have been attributed to climate change [4], overexploitation [5], or a combination of the two [6]. Rhinoceroses (Family: Rhinocerotidae) have a rich fossil history replete with iconic examples of climate-induced extinctions [7], but current pressures threaten to eliminate this group entirely.

Corrigendum: Developing informative microsatellite markers for non-model species using reference mapping against a model species' genome.

This corrects the article DOI: 10.1038/srep23087.

Geographic variation in advertisement calls of a Microhylid frog - testing the role of drift and ecology.

Acoustic signals for mating are important traits that could drive population differentiation and speciation. Ecology may play a role in acoustic divergence through direct selection (e.g.

Developing informative microsatellite markers for non-model species using reference mapping against a model species' genome.

Microsatellites have a wide range of applications from behavioral biology, evolution, to agriculture-based breeding programs. The recent progress in the next-generation sequencing technologies and the rapidly increasing number of published genomes may greatly enhance the current applications of microsatellites by turning them from anonymous to informative markers. Here we developed an approach to anchor microsatellite markers of any target species in a genome of a related model species, through which the genomic locations of the markers, along with any functional genes potentially linked to them, can be revealed.

Trophic cascade effects of avian predation on a willow in an urban wetland.

Trophic cascades play a crucial role in ecosystem functioning. In this study, we tested the effects of avian predation on willows (Salix warburgii) and associated arthropods in an urban wetland. We excluded birds by netting around willow branches for 20 months from September-November 2010 to June 2012.

Climate niche differentiation between two passerines despite ongoing gene flow.

Niche evolution underpins the generation and maintenance of biological diversity, but niche conservatism, in which niches remain little changed over time in closely related taxa, and the role of ecology in niche evolution are continually debated. To test whether climate niches are conserved in two closely related passerines in East Asia - the vinous-throated (Paradoxornis webbianus) and ashy-throated (P. alphonsianus) parrotbills - we established their potential allopatric and sympatric regions using ecological niche models and compared differences in their climate niches using niche overlap indices in background tests and multivariate statistical analyses.

Sex-specific effects of parasitism on survival and reproduction of a rodent host in a subtropical montane region.

Parasites can generate complex life history trade-offs in a host. In this study, we experimentally reduced the infection level of intestinal helminth parasites in the Taiwan field mouse (Apodemus semotus) to test (1) whether parasite richness and load are biased towards male or female mice (sex-biased parasitism) and (2) whether the effects of parasitism on the host's survival and reproduction are different between the sexes (sex-specific effects of parasitism). Our findings indicate that neither parasite richness (number of helminth taxa found in a fecal sample) nor parasite load (number of helminth eggs per gram of fecal material) was sexually biased in our A.

Drastic population fluctuations explain the rapid extinction of the passenger pigeon.

To assess the role of human disturbances in species' extinction requires an understanding of the species population history before human impact. The passenger pigeon was once the most abundant bird in the world, with a population size estimated at 3-5 billion in the 1800s; its abrupt extinction in 1914 raises the question of how such an abundant bird could have been driven to extinction in mere decades. Although human exploitation is often blamed, the role of natural population dynamics in the passenger pigeon's extinction remains unexplored.

Trophic niche width increases with bill-size variation in a generalist passerine: a test of niche variation hypothesis.

The niche variation hypothesis (NVH) predicts that populations with wider niches are phenotypically more variable than populations with narrower niches, which is frequently used to explain diversifying processes such as ecological release. However, not all empirical evidence supports the NVH. Furthermore, a relationship between population phenotypic variation and niche width can be caused by sexual selection or environmental gradients, which should be carefully considered along with competition in explaining niche variation.

Sex-specific correlations of individual heterozygosity, parasite load, and scalation asymmetry in a sexually dichromatic lizard.

Heterozygosity-fitness correlations (HFCs) provide insights into the genetic bases of individual fitness variation in natural populations. However, despite decades of study, the biological significance of HFCs is still under debate. In this study, we investigated HFCs in a large population of the sexually dimorphic lizard Takydromus viridipunctatus (Lacertidae).

Trophic shifts of a generalist consumer in response to resource pulses.

Trophic shifts of generalist consumers can have broad food-web and biodiversity consequences through altered trophic flows and vertical diversity. Previous studies have used trophic shifts as indicators of food-web responses to perturbations, such as species invasion, and spatial or temporal subsidies. Resource pulses, as a form of temporal subsidies, have been found to be quite common among various ecosystems, affecting organisms at multiple trophic levels.

Giving-updensity and dietary shifts in the white-footed mouse, Peromyscus leucopus.

Dietary shifts are commonly exhibited by omnivorous consumers when foraging from variable food resources. One advantage of dietary shifts for a consumer is the ability to gain complementary resources from different foods. In addition, dietary shifts often affect food-web dynamics.