Song evolution, speciation, and vocal learning in passerine birds

Phenotypic divergence can promote reproductive isolation and speciation, suggesting a possible link between rates of phenotypic evolution and the tempo of speciation at multiple evolutionary scales. To date, most macroevolutionary studies of diversification have focused on morphological traits, whereas behavioral traits─including vocal signals─are rarely considered. Thus, although behavioral traits often mediate mate choice and gene flow, we have a limited understanding of how behavioral evolution contributes to diversification. Furthermore, the developmental mode by which behavioral traits are acquired may affect rates of behavioral evolution, although this hypothesis is seldom tested in a phylogenetic framework. Here, we examine evidence for rate shifts in vocal evolution and speciation across two major radiations of codistributed passerines: one oscine clade with learned songs (Thraupidae) and one suboscine clade with innate songs (Furnariidae). We find that evolutionary bursts in rates of speciation and song evolution are coincident in both thraupids and furnariids. Further, overall rates of vocal evolution are higher among taxa with learned rather than innate songs. Taken together, these findings suggest an association between macroevolutionary bursts in speciation and vocal evolution, and that the tempo of behavioral evolution can be influenced by variation in developmental modes among lineages

Advanced measurement techniques for the characterization of ReRAM devices

In some Resistive Random Access Memories (ReRAM), which could become the next generation of non-volatile memories [1], the voltage-controlled high and low resistance states (HRS and LRS, respectively) are associated to the creation (Set) and disruption (Reset) of a conductive filament (CF) that locally connects (LRS) or disconnects (HRS) the electrodes [2]. Usually, a current limit (CL) must be fixed during the Set process. Typically, these devices are characterized using source measurement units (SMU) to measure the current through the device. However, most of the SMU have a low sampling rate (around 1sample/1ms) and the current limitation mechanism used by the equipment is not well understood. To overcome these limitations, in this work, a low-cost setup with large sampling rate (larger than 1sample/10μs) is presented which, in addition, includes a well-controlled wide-range current limiting unit, CLCU (Fig. 1). The system is suitable to capture fast transients during the Set/Reset processes (Fig. 2) and to detect HRS Random Telegraph Noise (RTN) unresolvable by SMUs (Fig. 3) [3]. These device-level measurements can be combined with a Conductive Atomic Force Microscope, to get information on CF properties that cannot be directly measured at device level, as, for example, the spatial distribution of current in the CF at LRS and HRS (Fig. 4) [4]. Please click Additional Files below to see the full abstract

Seasonal Movements of Chinook Salmon in Lake Michigan Based on Tag Recoveries from Recreational Fisheries and Catch Rates in Gill‐Net Assessments

There are no specific studies of the movements of introduced Chinook salmon Oncorhynchus tshawytscha in Lake Michigan, despite the need for such information for population assessments and stocking allocations. We investigated the seasonal distribution of hatchery‐reared Chinook salmon between May and September based on fishery‐dependent (recoveries from recreational fisheries of fish marked with coded wire tags [CWTs]) and fishery‐independent sources (catches in assessment gill‐net surveys). We modeled recoveries by fishing trips in Michigan waters of Lake Michigan to estimate spatially and temporally explicit abundance indices using generalized linear models (GLMs) and accounted for the efficiency among recovery sources (charter boat captain reports, creel clerk interviews, and headhunter collections of CWT samples from charter boat and non‐charter boat catches). Recovery levels varied among areas, months, years, and recovery sources, and distribution among areas also varied by month. We used CWT data with lakewide geographical coverage and evaluated the distributions of the absolute numbers of coded‐wire‐tagged fish recovered in Michigan and Wisconsin waters of Lake Michigan from all possible recovery sources. From both analyses we found that the distribution of Chinook salmon varied seasonally, with displacements from southern areas toward the north from May through summer, from inshore to offshore areas toward the west during summer, and movement back east in the fall. For the analysis of Chinook salmon catch rates in gill‐net assessments, we used GLMs to compare levels among months, statistical districts, years, nearshore and offshore areas, and different depths. The temporal and spatial trends were similar to those from the CWT analyses, and the distribution shifted toward deeper waters in July and August. Movement patterns coincided with favorable temperature and prey distribution and were consistent with those exhibited by the Pacific Ocean Chinook salmon population from which the Lake Michigan population originated. Seasonal changes in Chinook salmon distribution influence recreational fisheries, and stocking strategies should consider the influences of movement patterns on fishing opportunities in Lake Michigan.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142273/1/tafs0736.pd

Cientópolis: motorizando la ciencia ciudadana

En ciertas situaciones como la toma, clasificación y etiquetado de muestras, el científico realiza un gran número de tareas simples, repetitivas, que no pueden ser automatizadas y que podrían ser ejecutadas por personas sin formación en la materia si se las entrena y asiste con herramientas. En el pasado, en proyectos de conservación, astronomía y biología, entre otros, este tipo de tareas se ha delegado de manera efectiva a voluntarios. Cuando se convoca a ciudadanos voluntarios para colaborar con los científicos, se habla de ciencia ciudadana. Encontrar e involucrar a esos voluntarios, sumado a coordinar y reconocer su trabajo, es una tarea compleja. Definir y conducir proyectos de ciencia ciudadana presenta desafíos en tres áreas críticas: metodologías, tecnologías y construcción de comunidades de voluntarios. El proyecto Cientópolis (http://cientopolis.org) tiene como objetivo producir avances en estas tres áreas y socializarlos con la comunidad. En la actualidad, Cientópolis brinda espacios para compartir conocimiento y experiencias, ofrece herramientas para la construcción de proyectos de toma de muestras con dispositivos móviles y construcción colaborativa de conocimiento, da acceso a una comunidad creciente de ciudadanos científicos y explora estrategias de ludificación para consolidar y sostener dicha comunidad.Trabajo presentado por el Laboratorio de Investigación y Formación en Informática Avanzada (LIFIA

Defining principles for mobile apps and platforms development in citizen science

Apps for mobile devices and web-based platforms are increasingly used in citizen science projects. While extensive research has been done in multiple areas of studies, from Human-Computer Interaction to public engagement in science, we are not aware of a collection of recommendations specific for citizen science that provides support and advice for planning, design and data management of mobile apps and platforms that will assist learning from best practice and successful implementations. In two workshops, citizen science practitioners with experience in mobile application and web-platform development and implementation came together to analyse, discuss and define recommendations for the initiators of technology based citizen science projects. Many of the recommendations produced during the two workshops are applicable to citizen science project that do not use mobile devices to collect data. Therefore, we propose to closely connect the results presented here with ECSA’s Ten Principles of Citizen Science

3,5-Dimethyl-1-(4-nitro­phen­yl)-1H-pyrazole

In the title pyrazole derivative, C11H11N3O2, the benzene ring is twisted [dihedral angle = 31.38 (12)°] with respect to the pyrazole ring (r.m.s. deviation = 0.009 Å). The nitro group is effectively coplanar with the benzene ring to which it is attached [O—N—C—C torsion angle = −6.5 (3)°]. Supra­molecular chains along the b axis are formed owing to π–π inter­actions [3.8653 (2) Å] between translationally related mol­ecules involving both the five- and six-membered rings

Morphological adaptations linked to flight efficiency and aerial lifestyle determine natal dispersal distance in birds

Natal dispersal—the movement from birthplace to breeding location—is often considered the most significant dispersal event in an animal's lifetime. Natal dispersal distances may be shaped by a variety of intrinsic and extrinsic factors, and remain poorly quantified in most groups, highlighting the need for indices that capture variation in dispersal among species. In birds, it is hypothesized that dispersal distance can be predicted by flight efficiency, which can be estimated using wing morphology. However, the use of morphological indices to predict dispersal remains contentious and the mechanistic links between flight efficiency and natal dispersal are unclear. Here, we use phylogenetic comparative models to test whether hand-wing index (HWI, a morphological proxy for wing aspect ratio) predicts natal dispersal distance across a global sample of 114 bird species. In addition, we assess whether HWI is correlated with flight usage in foraging and daily routines. We find that HWI is a strong predictor of both natal dispersal distance and a more aerial lifestyle. Our results support the use of HWI as a valid proxy for relative natal dispersal distance, and also suggest that evolutionary adaptation to aerial lifestyles is a major factor connecting flight efficiency with patterns of natal dispersal

The Evolution Of A Tropical Biodiversity Hotspot

The tropics are the source of most biodiversity yet inadequate sampling obscures answers to fundamental questions about how this diversity evolves. We leveraged samples assembled over decades of fieldwork to study diversification of the largest tropical bird radiation, the suboscine passerines. Our phylogeny, estimated using data from 2389 genomic regions in 1940 individuals of 1287 species, reveals that peak suboscine species diversity in the Neotropics is not associated with high recent speciation rates but rather with the gradual accumulation of species over time. Paradoxically, the highest speciation rates are in lineages from regions with low species diversity, which are generally cold, dry, unstable environments. Our results reveal a model in which species are forming faster in environmental extremes but have accumulated in moderate environments to form tropical biodiversity hotspots