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Wisenden et al. (2020) reported differential behavioral responses by male Red-winged Blackbirds (Agelaius phoeniceus) to models bearing a red-epaulet visual signal with and without reflectance in the ultraviolet (UV) portion of the spectrum. O'Daniels et al. (2021) wrote a response, claiming that some of our key terminology was incorrect and that our methodology was potentially confounded, calling into question the veracity of the results reported in our study. Herein, we explain (1) our use of the term 'control' to be the treatment that lacks the test variable of interest: (2) the labels UV+and UV- refer to treatments that did, and did not, reflect in the UV; (3) that sunscreen likely did not contain methyl anthranilate, and even if it did, the amounts of sunscreen used were so small that it could not possibly explain the behavioral effects we observed over the distances between models and territorial males tested in the field; and (4) visual modeling would not enhance the interpretation or impact of our study. We do agree with O'Daniels et al. (2021) that additional field research should be done to better understand visual ecology and the evolution of avian plumage signals. Received 23 March 2021. Accepted 12 June 2021. Key words: signal evolution, territory defense, ultraviolet color, visual ecology. Wisenden et al. (2020) reportaron difcrcptes respuestas conductuales de machos del tordo Agelaius phoeniceus a modelos que portaban una scfia! visual de chaneteras rojas con y sin la reflectancia de la portion del espectro ultravioleta (UV). O'Daniels ct al. (2021) escribicron una respuesta a este trabajo. afipnando que nuestra terminologia clave era incorrccta y que nuestra metodologia estaba potcncialmente confundida. cucstionando la veracidad de los rcsultados que rcportamos en nuestro estudio. Aqui explicamos (1) nuestro uso del termino 'control' para el tratamiento que carcce de la variable de interes somctida a prueba; (2) el uso de la dcnominacion UV-fy UV- para referirnos a los tratamientos que reflejaban y no reflejaban la UV; (3) que el bloqucador solar muy posiblcmente no contcnia metil antranilato, y si lo hubiesc tenido. las cantidades utilizadas fueron tan pcqucnas que no podrian cxplicar los cfectos conductuales que observamos a las distancias entre modelos y machos territoriales sometidos a paicba en el campo y (4) que el modclado visual no aumentaria la interpretacion o impacto de nuestro estudio. Estamos de acuerdo con O'Daniels et al. (2021) que deberia haccrse investigacion de campo adicional para entender mejor la ecologia visual y la evolucion de las sefiales visuales del plumaje de las aves. Palabras clave: color ultravioleta. defensa de territorio, ecologia visual, evolucion de sefiales., We performed a simple experiment comparing the behavioral responses of territorial male Red-winged Blackbirds (Agelaius phoeniceus) to model puppets made from black cotton socks, with patches of felt sewn onto [...]

Male Red-winged Blackbirds (Agelaius phoeniceus) have red epaulets that are used as badges for intrasexual competition for territory acquisition and defense. Red epaulets reflect very little across ultraviolet (UV) wavelengths (300-400 nm) yet most birds, including Red-winged Blackbirds, are visually sensitive to UV light. Here, we conducted a field experiment to test if adding UV reflectance (UV+) to epaulets changed the effectiveness of signals to receivers relative to control epaulets. We constructed blackbird models with an epaulet made from red felt that reflected both long-wavelength (i.e., red) and UV wavelengths (UV+). To half of the models we applied sunscreen over the epaulets to block UV reflectance (UV-) and therefore mimic reflectance spectra of natural epaulets. UV+ and UV- models, along with small playback recorders playing oak-a-lee calls, were presented in established territories of male Red-winged Blackbirds. UV+ models received significantly more song flight displays (2017) and song spread displays (2019) from territorial males. Two territorial males physically attacked UV+ models but none attacked UV- models. To our knowledge, this is the first field experiment to add UV color to a plumage signal, resulting in a behavioral response from wild birds, raising questions for future research to explore a potential pre-existing visual bias for UV coloration in Red-winged Blackbirds and potential phylogenetic constraints on expression of UV reflectance of epaulets. Received IS October 2018. Accepted 12 March 2020. Key words: signal evolution, territory defense, ultraviolet color Los machos del tordo Agelaius phoeniceus tienen charreteras rojas que utilizan como distintivos en la competencia intrasexual por adquisición de territorio y defensa. Las charreteras rojas reflejan muy poco de las longitudes de onda ultravioleta (UV, de 300-400 nm) si bien la mayoría de las aves, incluidos estos tordos, son visualmente sensibles a la luz UV. Llevamos a cabo un experimento de campo para probar si la adición de reflectancia ultravioleta (UV+) a las charreteras cambia la efectividad de las señales hacia sus receptores con relación a charreteras control. Construimos modelos de tordo con charreteras hechas de fieltro rojo que reflejaban rojos con longitudes de onda largas y longitudes de onda UV+. A la mitad de estos modelos les aplicamos bloqueador solar sobre las charreteras para impedir la reflectancia ultravioleta (UV-) y con ello imitar la reflectancia espectral de charreteras naturales. Los modelos UV+y UV-, junto con pequeñas grabadoras que tocan los llamados ouc-a-lii, fueron expuestos en territorios de tordos machos establecidos. Los modelos UV+ recibieron un número significativamente mayor de despliegues 'canto en vuelo' (2017) y despliegues 'canto extendido' (2019) por parte de machos territoriales. Dos machos territoriales atacaron físicamente los modelos UV+ aunque ninguno atacó a los modelos UV-. Por lo que sabemos, este es el primer experimento de campo para agregar color UV a una señal de plumaje para obtener una señal de comportamiento de aves silvestres, lo que genera nuevas preguntas a investigarse en el futuro como explorar el potencial sesgo visual por la coloración UV y las potenciales limitaciones filogenéticas en la expresión de la reflectancia UV de sus charreteras. Palabras clave: color ultravioleta, defensa de territorio, evolución de señales, Bird plumage has been intensively studied for communication in displays of resource holding potential, mate quality, and social status (e.g., Hill 1991). Carotenoid-based pigments signal successful foraging history and immunocompetence, [...]

We present a detailed response to the critique of "State of the Science of Endocrine Disrupting Chemicals 2012" (UNEP/WHO, 2013) by financial stakeholders, authored by Lamb et al. (2014). Lamb et al.'s claim that UNEP/WHO (2013) does not provide a balanced perspective on endocrine disruption is based on incomplete and misleading quoting of the report through omission of qualifying statements and inaccurate description of study objectives, results and conclusions. Lamb et al. define extremely narrow standards for synthesizing evidence which are then used to dismiss the UNEP/WHO 2013 report as flawed. We show that Lamb et al. misuse conceptual frameworks for assessing causality, especially the Bradford-Hill criteria, by ignoring the fundamental problems that exist with inferring causality from empirical observations. We conclude that Lamb et al.'s attempt of deconstructing the UNEP/WHO (2013) report is not particularly erudite and that their critique is not intended to be convincing to the scientific community, but to confuse the scientific data. Consequently, it promotes misinterpretation of the UNEP/WHO (2013) report by non-specialists, bureaucrats, politicians and other decision makers not intimately familiar with the topic of endocrine disruption and therefore susceptible to false generalizations of bias and subjectivity.

The "common sense" intervention by toxicology journal editors regarding proposed European Union endocrine disrupter regulations ignores scientific evidence and well-established principles of chemical risk assessment. In this commentary, endocrine disrupter experts express their concerns about a recently published, and is in our considered opinion inaccurate and factually incorrect, editorial that has appeared in several journals in toxicology. Some of the shortcomings of the editorial are discussed in detail. We call for a better founded scientific debate which may help to overcome a polarisation of views detrimental to reaching a consensus about scientific foundations for endocrine disrupter regulation in the EU. © 2013 Bergman et al.; licensee BioMed Central Ltd.

A fast-ion deuterium alpha (FIDA) spectrometer was installed on MAST to measure radially resolved information about the fast-ion density and its distribution in energy and pitch angle. Toroidally and vertically directed collection lenses are employed, to detect both passing and trapped particle dynamics, and reference views are installed to subtract the background. This background is found to contain a substantial amount of passive FIDA emission driven by edge neutrals, and to depend delicately on viewing geometry. Results are compared with theoretical expectations based on the codes NUBEAM (for fast-ion distributions) and FIDASIM. Calibrating via the measured beam emission peaks, the toroidal FIDA signal profile agrees with classical simulations in magnetohydrodynamic quiescent discharges where the neutron rate is also classical. Long-lived modes (LLMs) and chirping modes decrease the core FIDA signal significantly, and the profile can be matched closely to simulations using anomalous diffusive transport; a spatially uniform diffusion coefficient is sufficient for chirping modes, while a core localized diffusion is better for a LLM. Analysis of a discharge with chirping mode activity shows a dramatic drop in the core FIDA signal and rapid increase in the edge passive signal at the onset of the burst indicating a very rapid redistribution towards the edge. Vertical-viewing measurements show a discrepancy with simulations at higher Doppler shifts when the neutron rate is classical, which, combined with the fact that the toroidal signals agree, means that the difference must be occurring for pitch angles near the trapped-passing boundary, although uncertainties in the background subtraction, which are difficult to assess, may contribute to this. Further evidence of an anomalous transport mechanism for these particles is provided by the fact that an increase of beam power does not increase the higher energy vertical FIDA signals, while the toroidal signals do increase. © 2013 IOP Publishing Ltd.

Differences in coloration between the sexes (sexual dichromatism) can increase or decrease in a species through evolutionary changes in either or both sexes diverging or converging in their colors. Few previous studies, however, have examined the relative rates of such changes, particularly when dichromatism is lost. Using reflectance data from 37 species of the New World blackbird family (Icteridae), we compared evolutionary rates of plumage color change in males and females when dichromatism was either increasing (colors diverging) or decreasing (colors converging). Increases in dichromatism involved divergent changes in both sexes at approximately equal rates. Decreases in dichromatism, in contrast, involved changes in females to match male plumage colors that were significantly more rapid than any changes in males. Such dramatic changes in females show how selection can differ between the sexes. Moreover, these evolutionary patterns support the idea that losses of dimorphism involve genetic mechanisms that are already largely present in both sexes, whereas increases in dimorphism tend to involve the appearance of novel sex-specific traits, which evolve more slowly. Our results have broad implications for how sexual dimorphisms evolve. [ABSTRACT FROM AUTHOR]