Abstract Quantifying “demographic independence” is a vital step in establishing potential conservation units for species that it effectively distinguishes migration from within‐population reproduction. This an important aspect because allows accurate estimate of recruitment. For example, populations may be designated as 'management units' (=MUs) if indeed population growth results local demography rather than immigration. Of additional interest the calculation immigrant ancestry and...

in gut analyses; and (c) 34 head, fin, body measurements. Ecological data were arcsine transformed, while morphological converted first into common logarithms, then canonical variate scores from a sheared principal components analysis. A taxonomic matrix based on accepted phylogenetic relationships amongst species of the assemblage was also constructed. Microhabitat, trophic, morphological, matrices compared against one another using pair-wise Mantel tests, correlation analyses, three-way...

This review will describe the unique advantages that are offered by visual system of mammals and other vertebrates for studying regenerative responses central nervous (CNS) to injury, recent insights provided such studies. In mouse rat a variety experimental paradigms promote survival retinal ganglion cells (RGC) optic nerve regeneration, probably through stimulation neurotrophic factors (NTF) either directly, or indirectly astrocyte/Müller cell intermediary activation. NTF induce...

Morphological and genetic characters from cyprinid fishes of the genus Gila were examined to assess a hypothesized hybrid origin seminuda Virgin River, Arizona-Nevada-Utah. The presumed parents, robusta elegans, are clearly differentiated one another based on morphology, allozymes, mtDNA haplotypes. G. is morphologically intermediate polymorphic at allozyme loci diagnostic for parental species. Restriction endonuclease analysis showed nearly identical elegans. These results support an...

Genetic diversity in remnant populations of the Sonoran topminnow Poeciliopsis occidentalis (Pisces: Poeciliidae) from Arizona, where species is endangered, compared with that Sonora, Mexico, fish widespread and abundant. Geographically peripheral Arizona contain substantially lower levels genetic variation than do Mexican near center species' range. Allelic differences among three genetically geographically distinct groups are responsible for 53 percent total this species, 26 due to local...

During Pleistocene, the Laurentide ice sheet rearranged and diversified biotic distributions in eastern North America, yet had minimal physical impact western America where lineage diversification is instead hypothesized to result from climatic changes. If Pleistocene fluctuations impacted desert species, latter would reflect patterns of restricted gene flow concomitant with indications demographic bottlenecks. Accordingly, molecular evidence for refugia should be present within these...

ern North America by the nonnative red shiner (Cyprinella lutrensis) seems linked with dramatic decline of a threatened cyprinid (spikedace, Medafulgida) native to Gila River subbasin. The mechanism which impacts spikedace is unknown. Two hypotheses have been offered: displacement through competitive interaction invader, and replacement as result environmental perturbation. To ascertain whether was being actively displaced shiner, we compared niche requirements each in syntopy, allotopy,...

Fishes in the Little Colorado River Grand Canyon, Arizona, were sampled monthly from July 1991 to June 1995 as part of a study ecology endangered humpback chub Gila cypha. Diets five introduced predatory fish species examined. Stomach contents varied among and low diversity dominated by algae (primarily Cladophora), aquatic insects, fishes. Humpback plus other native significant component diet (13.7% frequency occurrence 219 408 stomachs that contained food). Predation mortality fishes may...

The present study investigated the effects of supporting both English and Spanish on language outcomes in bilingual children with hearing loss (HL) who used listening devices (cochlear implants aids). skills HL were compared to those their monolingual English-speaking peers' HL. participants also compared.The 40 (20 Spanish-English-speaking 20 English-speaking) examined using Auditory Comprehension, Expressive Communication, total scores from Preschool Language Scale, Fourth Edition (...

Abstract Background There is a critical need to understand better speech and language development in bilingual children learning two spoken languages who use cochlear implants (CIs) hearing aids (HAs). The paucity of knowledge this area poses significant barrier providing maximal communicative outcomes growing number have loss (HL) are multiple languages. In fact, the individuals receiving CIs HAs rapidly increasing, Hispanic display higher prevalence HL than general population United...

Abstract The landscape can influence host dispersal and density, which in turn, affect infectious disease transmission, spread, persistence. Understanding how the influences wildlife pathogen epidemiology enhance efficacy of management natural populations. We applied genetics to examine relationships among variables, white‐tailed deer hosts transmission/spread chronic wasting (CWD), a fatal prion encephalopathy. Our focus was on quantifying movements population structure infected areas as...

Research on the molecular ecology of non-model organisms, while previously constrained, has now been greatly facilitated by advent reduced-representation sequencing protocols. However, tools that allow these large datasets to be efficiently parsed are often lacking, or if indeed available, then limited necessity a comparable reference genome as an adjunct. This, course, can difficult when working with organisms. Fortunately, pipelines currently available avoid this prerequisite, thus...

Initiation of reproductive migration, structure the breeding population, and length season in Ambystoma jeffersonianum were studied for two consecutive winters at a small, sylvan pond Kentucky. Early response to cues temperature precipitation, continued movement under declining nocturnal temperatures enabled males arrive sooner greater numbers than females, who frequently moved later prolonged periods favorable conditions. During 1973, conditions favorable, arrived stayed significantly...

Abstract Global climate change is apparent within the A rctic and south‐western deserts of N orth merica, with record drought in latter reflected 640 000 km 2 C olorado R iver B asin. To discern manner by which natural anthropogenic drivers have compressed asin‐wide fish biodiversity, to establish a baseline for future effects, S tream H ierarchy M odel ( SHM ) was employed juxtapose fluvial topography against molecular diversities 1092 luehead ucker atostomus discobolus ). t DNA revealed...

Biodiversity elements with narrow niches and restricted distributions (i.e., 'short range endemics,' SREs) are particularly vulnerable to climate change. The New Mexico Ridge-nosed Rattlesnake (Crotalus willardi obscurus, CWO), an SRE listed under the U.S. Endangered Species Act within three sky islands of southwestern North America, is constrained at low elevation by drought high wildfire. We combined long-term recapture molecular data demographic niche modeling gauge its climate-driven...

Morphological data are a conduit for the recognition and description of species, their acquisition has recently been broadened by geometric morphometric (GM) approaches that co-join collection digital with exploratory 'big data' analytics. We employed this approach to dissect Western Rattlesnake (Crotalus viridis) species-complex in North America, currently partitioned mitochondrial (mt)DNA analyses into eastern western lineages (two seven subspecies, respectively). The GM (i.e., 33 dorsal...