Testing the strength and direction of selection on vocal frequency using metabolic scaling theory

A major challenge for studies assessing drivers of phenotypic divergence is the statistical comparison of taxa with unique, often unknown, evolutionary histories, and for which there are no clear expected trait values. Because many traits are fundamentally constrained by energy availability, we suggest that trait values predicted by scaling theories such as the metabolic theory of ecology (MTE) can provide baseline expectations. Here, we introduce a metabolic scaling-based approach to test theory involving the direction and magnitude of ecological and sexual selection, using vocal frequency as an example target of selection. First, we demonstrate that MTE predicts the relationship between the natural log of body size and natural log of vocal frequency across 795 bird species, controlling for phylogeny. Family-wide deviations in slope and intercepts from MTE estimates reveal taxa with potentially important differences in physiology or natural history. Further, species-level frequency deviations from MTE expectations are predicted by factors related to ecological and sexual selection and, in some cases, provide evidence that differs from current understanding of the direction of selection and identity of ecological selective agents. For example, our approach lends additional support to the findings from many cross-habitat studies that suggest that dense vegetation selects for lower frequency signals. However, our analysis also suggests that birds in non-forested environments vocalize at frequencies higher than expected based on MTE, prompting intriguing questions about the selective forces in non-forest environments that may act on vocal frequency. Additionally, vocal frequency deviates more strongly from MTE expectations among species with smaller repertoires and those with low levels of sexual dichromatism, complicating the use of these common sexual selection surrogates. Broad application of our metabolic scaling approach might provide an important complementary approach to understanding how selection shapes phenotypic evolution by offering a common baseline across studies and taxa and providing the basis to explore evolutionary trade-offs within and among multicomponent and multimodal traits

Multimodal signalling in the North American barn swallow: a phenotype network approach

Complex signals, involving multiple components within and across modal- ities, are common in animal communication. However, decomposing complex signals into traits and their interactions remains a fundamental challenge for studies of phenotype evolution. We apply a novel phenotype network approach for studying complex signal evolution in the North American barn swallow (Hirundo rustica erythrogaster). We integrate model testing with correlation-based phenotype networks to infer the contributions of female mate choice and male–male competition to the evolution of barn swallow communication. Overall, the best predictors of mate choice were distinct from those for competition, while moderate functional overlap suggests males and females use some of the same traits to assess potential mates and rivals. We interpret model results in the context of a network of traits, and suggest this approach allows researchers a more nuanced view of trait clustering patterns that informs new hypotheses about the evolution of communication systems. 3 supplemental files attached below

Positive Carotenoid Balance Correlates with Greater Reproductive Performance in a Wild Bird

Background: Carotenoids can confer somatic and reproductive benefits, but most evidence is from captive animal experimentation or single time-point sampling. Another perhaps more informative means by which to assess physiological contributions to animal performance is by tracking an individual’s ability to increase or sustain carotenoids or other healthrelated molecules over time, as these are likely to be temporally variable. Methodology/Principal Findings: In a field study of North American barn swallows (Hirundo rustica erythrogaster), we analyzed within-individual changes in carotenoid concentrations by repeatedly sampling the carotenoid profiles of individuals over the course of the breeding season. Our results demonstrate that carotenoid concentrations of individuals are temporally dynamic and that season-long balance of these molecules, rather than single time-point samples, predict reproductive performance. This was true even when controlling for two important variables associated with reproductive outcomes: (1) timing of breeding and (2) sexually selected plumage coloration, which is itself positively correlated with and concomitantly changes with circulating carotenoid concentrations. Conclusions/Significance: While reproduction itself is purported to impose health stress on organisms, these data suggest that free-ranging, high-quality individuals can mitigate such costs, by one or several genetic, environmental (diet), or physiological mechanisms. Moreover, the temporal variations in both health-linked physiological measures an

Cyberinfrastructure, Science Gateways, Campus Bridging, and Cloud Computing

Computers accelerate our ability to achieve scientific breakthroughs. As technology evolves and new research needs come to light, the role for cyberinfrastructure as “knowledge” infrastructure continues to expand. This article defines and discusses cyberinfrastructure and the related topics of science gateways and campus bridging; identifies future challenges in cyberinfrastructure; and discusses challenges and opportunities related to the evolution of cyberinfrastructure, “big data” (datacentric, data-enabled, and data-intensive research and data analytics), and cloud computing.This material is based upon work supported by the National Science Foundation under grants 0504075, 0451237, 0723054, 1062432, 0116050, 0521433, 0503697, and 1053575, and several IBM Shared University Research grants and support provided by Lilly Endowment, Inc. for the Indiana University Pervasive Technology Institute. Any opinions, findings and conclusions or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the supporting agencies

The Effect of Hair Color on the Incorporation of Codeine into Human Hair

The influence of melanin on the binding of xenobiotics in hair will impact the interpretation of drug concentrations determined by hair testing. The purpose of this study was to determine if codeine, as a model compound of abused drugs, would be incorporated into black, brown, blond, or red hair as a function of melanin concentration. Such data would assist in the interpretation of codeine concentrations in hair and help elucidate the potential influence of hair color on incorporation of drugs. Male and female Caucasians with black (n = 6), brown (n = 12), blond (n = 8), or red hair (n = 6) and non-Caucasians with black hair (n = 12) aged 21-40 years were enrolled in the study. Each subject was administered oral codeine phosphate syrup in a dosage of 30 mg three times a day for five days. Twenty-four hours after the end of the treatment period, a 30-mg codeine dose was administered and the subject's plasma area under the concentration time curve (AUC) for codeine was determined. Codeine and melanin were measured in the first 3 cm of hair closest to the vertex region of the scalp prior to and 1, 4, 5, 6, and 7 weeks after dosing. The quantitative and qualitative melanin profiles were determined for each subjects hair to provide an objective measure of hair color. The plasma concentrations of codeine were measured to eliminate differences in the bioavailability and clearance of codeine as factors that might account for the differences in codeine hair concentrations. The subjects were asked not to cut their hair in the vertex region of the scalp or to use any form of chemical treatment on their hair, but otherwise normal hygienic measures were permitted. The mean (± SE) hair codeine concentrations 5 weeks after dosing were 1429 (± 249) pg/mg in black hair; 208 (± 17) pg/mg in brown hair; 99 (± 10) pg/mg in blond hair; and 69 (± 11) in red hair pg/mg. In black hair, codeine concentrations were 2564 (± 170) pg/mg for Asians and 865 (± 162) pg/mg for Caucasians. Similar concentration relationships were observed at weeks 4, 6, and 7. A strong relationship between the hair concentrations of codeine and melanin (R2 = 0.73) was observed. Normalization of the codeine concentration with the melanin concentration reduced the hair color differences observed. These data demonstrate that the interpretation and reporting of hair test results for codeine are influenced by hair color. After this dosing protocol, the proposed federal guideline cutoff of 200 pg/mg of codeine would result in 100% of subjects with black hair and 50% of subjects with brown hair being reported as positive, and subjects with blond or red hair would be reported as negative. The incorporation of these drugs into hair should be studied carefully in humans to ensure the appropriate interpretation of drug concentration

PAI-1: An Integrator of Cell Signaling and Migration

Cellular migration, over simple surfaces or through complex stromal barriers, requires coordination between detachment/re-adhesion cycles, involving structural components of the extracellular matrix and their surface-binding elements (integrins), and the precise regulation of the pericellular proteolytic microenvironment. It is now apparent that several proteases and protease inhibitors, most notably urokinase plasminogen activator (uPA) and plasminogen activator inhibitor type-1 (PAI-1), also interact with several cell surface receptors transducing intracellular signals that significantly affect both motile and proliferative programs. These events appear distinct from the original function of uPA/PAI-1 as modulators of the plasmin-based proteolytic cascade. The multifaceted interactions of PAI-1 with specific matrix components (i.e., vitronectin), the low-density lipoprotein receptor-related protein-1 (LRP1), and the uPA/uPA receptor complex have dramatic consequences on the migratory phenotype and may underlie the pathophysiologic sequalae of PAI-1 deficiency and overexpression. This paper focuses on the increasingly intricate role of PAI-1 as a major mechanistic determinant of the cellular migratory phenotype

Selection on multiple sexual signals in two Central and Eastern European populations of the barn swallow

Variation in intensity and targets of sexual selection on multiple traits has been suggested to play a major role in promoting phenotypic differentiation between populations, although the divergence in selection may depend on year, local conditions or age. In this study, we quantified sexual selection for two putative sexual signals across two Central and East European barn swallow (Hirundo rustica rustica) populations from Czech Republic and Romania over multiple years. We then related these differences in selection to variation in sexual characters among barn swallow populations. Our results show that tail length and ventral coloration vary between populations, sexes, and age classes (first‐time breeders vs. experienced birds). We found that selection on tail length was stronger in first‐time breeders than in experienced birds and in males than in females in the Romanian population, while these differences between age groups and sexes were weak in Czech birds. We suggest that the populational difference in selection on tail length might be related to the differences in breeding conditions. Our results show that ventral coloration is darker (i.e., has lower brightness) in the Romanian than in the Czech population, and in experienced birds and males compared with first‐time breeders and females, respectively. The sexual difference in ventral coloration may suggest sexual selection on this trait, which is supported by the significant directional selection of ventral coloration in first‐time breeding males on laying date. However, after controlling for the confounding effect of wing length and tarsus length, the partial directional selection gradient on this trait turned nonsignificant, suggesting that the advantage of dark ventral coloration in early breeding birds is determined by the correlated traits of body size. These findings show that ventral coloration may be advantageous over the breeding season, but the underlying mechanism of this relationship is not clarified

Comparison of two multiple-locus variable-number tandem-repeat analysis methods for molecular strain typing of human Brucella melitensis isolates from the Middle East

Brucella species are highly monomorphic, with minimal genetic variation among species, hindering the development of reliable subtyping tools for epidemiologic and phylogenetic analyses. Our objective was to compare two distinct multiple-locus variable-number tandem-repeat analysis (MLVA) subtyping methods on a collection of 101 Brucella melitensis isolates from sporadic human cases of brucellosis in Egypt (n = 83), Qatar (n = 17), and Libya (n = 1). A gel-based MLVA technique, MLVA-15IGM, was compared to an automated capillary electrophoresis-based method, MLVA-15NAU, with each MLVA scheme examining a unique set of variable-number tandem repeats. Both the MLVAIGM and MLVANAU methods were highly discriminatory, resolving 99 and 101 distinct genotypes, respectively, and were able to largely separate genotypes from Egypt and Qatar. The MLVA-15NAU scheme presented higher strain-to-strain diversity in our test population than that observed with the MLVA-15IGM assay. Both schemes were able to genetically correlate some strains originating from the same hospital or region within a country. In addition to comparing the genotyping abilities of these two schemes, we also compared the usability, limitations, and advantages of the two MLVA systems and their applications in the epidemiological genotyping of human B. melitensis strains

STAT3 regulates cytotoxicity of human CD57+ CD4+ T cells in blood and lymphoid follicles

A subset of human follicular helper T cells (TFH) cells expresses CD57 for which no distinct function has been identified. We show that CD57+ TFH cells are universally PD-1hi, but compared to their CD57− PD-1hi counterparts, express little IL-21 or IL-10 among others. Instead, CD57 expression on TFH cells marks cytotoxicity transcriptional signatures that translate into only a weak cytotoxic phenotype. Similarly, circulating PD-1+ CD57+ CD4+ T cells make less cytokine than their CD57− PD-1+ counterparts, but have a prominent cytotoxic phenotype. By analysis of responses to STAT3-dependent cytokines and cells from patients with gain- or loss-of-function STAT3 mutations, we show that CD4+ T cell cytotoxicity is STAT3-dependent. TFH formation also requires STAT3, but paradoxically, once formed, PD-1hi cells become unresponsive to STAT3. These findings suggest that changes in blood and germinal center cytotoxicity might be affected by changes in STAT3 signaling, or modulation of PD-1 by therapy.This work was supported by National Health and Medical Research Council (Australia) program grants APP1016953 and APP427620 (CGV, CCG, SGT, MCC)