J. F. Schaefer results 32
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Reproductive timing and clutch parameters of the pearl darter, Percina aurora , in the Pascagoula River drainageNARA Subscribed
Understanding the timing, duration and effort put into reproduction is vital to successful management of any species. The southeastern United States is home to tremendous levels of aquatic biodiversity and was recently named one of the Earth's biodiversity hotspots. For some species, the fundamentals of age, growth, reproductive timing and ecology remain poorly understood. Percina aurora , the pearl darter, has been recently l...
The natural history and genotype–phenotype correlations of TMPRSS3 hearing loss: an international, multi-center, cohort analysisNARA Subscribed
TMPRSS3 -related hearing loss presents challenges in correlating genotypic variants with clinical phenotypes due to the small sample sizes of previous studies. We conducted a cross-sectional genomics study coupled with retrospective clinical phenotype analysis on 127 individuals. These individuals were from 16 academic medical centers across 6 countries. Key findings revealed 47 unique TMPRSS3 variants with significant differe...
Identifying active retrogressive thaw slumps from ArcticDEMNARA Subscribed
Ants, an ecologically successful and numerically dominant group of animals, play key ecological roles as soil engineers, predators, nutrient recyclers, and regulators of plant growth and reproduction in most terrestrial ecosystems. Further, ants are widely used as bioindicators of the ecological impact of land use. We gathered information of ant species in the Atlantic Forest of South America. The ATLANTIC ANTS data set, which...
Heatwave‐induced synchrony within forage fish portfolio disrupts energy flow to top pelagic predatorsNARA Subscribed
During the Pacific marine heatwave of 2014–2016, abundance and quality of several key forage fish species in the Gulf of Alaska were simultaneously reduced throughout the system. Capelin ( Mallotus catervarius ), sand lance ( Ammodytes personatus ), and herring ( Clupea pallasii ) populations were at historically low levels, and within this community abrupt declines in portfolio effects identify trophic instability at the onse...
Comparative genetic isolation patterns for multiple headwater fishes in three geographic regionsNARA Subscribed
Headwater‐resident fishes may be prone to a high rate of isolation and a pronounced hierarchical genetic structure due to a combination of niche preference and dendritic effects of river networks. Genetic isolation patterns were compared using microsatellites in six headwater fishes, Fundulus olivaceus , Semotilus atromaculatus , Erimyzon claviformis , Etheostoma artesiae , Etheostoma whipplei and Etheostoma parvipinne , in th...
A rearing experiment was conducted to test whether temperature protocols that differed from a simulation of natural conditions might induce maturation after isothermal grow‐out in burbot Lota lota . Lota lota were acclimated to two different temperature regimes: low temperature ( LT ), close to natural temperature at 4·0° C and elevated, high temperature ( HT ) at 8·5° C over 40 and 27 days respectively, with all fish then win...
A total of 17 polymorphic microsatellite loci were isolated from the blackstripe topminnow Fundulus notatus . In a sample of 29 individuals, these loci were found to possess two to 19 alleles with expected heterozygosity values ranging from 0·212 to 0·919 and all but one of the loci conformed to Hardy–Weinberg equilibrium expectations. Many of these loci were polymorphic in the closely related species Fundulus olivaceus and Fu...
Harmonic analysis of climatological temperature over Antarctica: present day and greenhouse warming perspectivesNARA Subscribed
On the basis of ERA40 and NCEP/NCAR Reanalysis (NNR) and simulations from CCCma, CCSM, CSIRO, HadCM3, MIROC‐MEDRES and GFDL, which support the Intergovernmental Panel on Climate Change (IPCC) 4th Assessment Report (AR4), we demonstrated that the amplitude of the annual and the semi‐annual harmonics delivered by the ERA40 and NNR is dominated by distinct seasonal variability. The maximum first harmonic amplitude of near surface...
A new species of Profundulus (Cyprinodontiformes: Profundulidae) from the Honduran central highlandsNARA Subscribed
A new species of Profundulus , Profundulus portillorum , from the Honduran central highlands is described. Profundulus portillorum belongs to the Profundulus labialis species group and is distinct from the Profundulus punctatus species group in that it lacks a humeral spot and less than half of the caudal fin is scaled. Within the P. labialis species group, P. portillorum has a more slender body, smaller eye, fewer anal rays,...
Seven years of recent European net terrestrial carbon dioxide exchange constrained by atmospheric observationsNARA Subscribed
We present an estimate of net ecosystem exchange (NEE) of CO 2 in Europe for the years 2001–2007. It is derived with a data assimilation that uses a large set of atmospheric CO 2 mole fraction observations (∼70 000) to guide relatively simple descriptions of terrestrial and oceanic net exchange, while fossil fuel and fire emissions are prescribed. Weekly terrestrial sources and sinks are optimized (i.e., a flux inversion) for...
A phylogeny of the six North American species in the genus Alosa , with representatives of three Eurasian species, was generated using mtDNA sequences. This was accomplished by obtaining sequences for three North American species and additional geographical sampling of the other three species. The subgenus Alosa , including the formerly recognized subgenus Caspialosa , formed a strongly supported monophyletic group. Alosa alab...