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Level lifetimes for the candidate chiral doublet bands of $^{80}$Br were extracted by means of the Doppler-shift attenuation method. The absolute transition probabilities derived from the lifetimes agree well with the M1 and E2 chiral electromagnetic selection rules, and are well reproduced by the triaxial particle rotor model calculations. Such good agreements among the experimental data, selection rules of chiral doublet bands and theoretical calculations are rare and outstanding in researches of nuclear chirality. Besides odd-odd Cs isotopes, odd-odd Br isotopes in the A≈ 80 mass region represent another territory that exhibits the ideal selection rules expected for chiral doublet bands.

International audience; In preparation of the Thermal infraRed Imaging Satellite for High-resolution Natural resource Assessment (TRISHNA) mission, we conducted a thorough analysis of sensitivity for the Temperature-Emissivity Separation (TES) method to the position of the four TRISHNA spectral channels, notably to find an optimal spectral configuration. To that purpose, we designed a fast-computing end-to-end simulator including several components, which we implemented to simulate both pixel-size TRISHNA measurements and land surface temperature (LST) retrievals. Firstly, simulations were conducted over a wide range of realistic scenarii, notably by including vegetation canopy-scale cavity effect. Secondly, the experimental design included the features of second generation Mercury-Cadmium-Telluride (MCT) cooled detectors with lower instrumental noises and finer channels. Thirdly, as opposed to previous studies that used predefined spectral configurations to determine the most suited one, we conducted an optimization of the spectral configuration by crossing, on a pair basis, several positions of the four TIR channels over a range of wavelengths. Fourthly, we quantified the TES sensitivity to atmospheric perturbations, by comparing LST retrievals with and without atmospheric noise.We observed an overall moderate sensitivity of TES LST retrievals to the spectral channel positions, with a maximum RMSE variation of 0.31 K within the atmospheric spectral windows. Furthermore, the TES method was sensitive to three main parameters, namely the instrumental noise, the atmospheric downwelling irradiance, and the transmittance due to ozone and water vapor, with RMSEs larger than 1 K for specific channel locations. Moreover, by considering possible superimposition of two channels, we noted that the TES method could achieve similar performance by considering three or four channels. Eventually, our study enabled us to recommend a new spectral configuration for the TRISHNA TIR instrument, that is more robust to atmospheric perturbations and to uncertainties on channel positions and bandwidths.

Closely related taxa are, on average, more similar in terms of their physiology, morphology and ecology than distantly related ones. How this biological similarity affects geochemical signals, and their interpretations, has yet to be tested in an explicitly evolutionary framework. Here, we compile and analyze planktonic foraminiferal size-specific stable carbon and oxygen isotope values (δ13C and δ18O) spanning the last 107 million years. After controlling for dominant drivers of size-δ13C and δ18O trends, such as geological preservation, presence of algal photosymbionts and global environmental trends, we identify that shared evolutionary history has shaped the evolution of species-specific “vital effects” in δ13C, but not in δ18O. Our results lay the groundwork for using a phylogenetic approach to ‘correct’ species δ13C vital effects through time, thereby reducing systematic biases in interpretations of long-term δ13C records – a key measure of holistic organismal biology and of the global carbon cycle.

The influence of within-species variation and covariation on evolutionary patterns is well established for generational and macroevolutionary processes, most prominently through genetic lines of least resistance. However, it is not known whether intraspecific phenotypic variation also directs microevolutionary trajectories into the long term when a species is subject to varying environmental conditions. Here we present a continuous, high-resolution bivariate record of size and shape changes among 12,633 individual planktonic foraminifera of a surviving and an extinct-going species over 500 thousand years. This time interval spans the late Pliocene to earliest Pleistocene intensification of Northern Hemisphere glaciation, an interval of profound climate upheaval that can be divided into three phases of increasing glacial intensity. We found that within each of these three Plio-Pleistocene climate phases the within-population allometries predict evolutionary change from one time-step to the next, and that the within-phase among-population (i.e. evolutionary) allometries match their corresponding static (within-population) allometries. However, the evolutionary allometry across the three climate phases deviates significantly from the static and phase-specific evolutionary allometries in the extinct-going species. Although intraspecific variation leaves a clear signature on mean evolutionary change from one time-step to the next, our study suggests that the link between intraspecific variation and longer-term micro- and macroevolutionary phenomena is prone to environmental perturbation that can overcome constraints induced by within-species trait covariation.

Most polygynous male mammals exhibit little or no parental care or involvement raising young. Instead, they invest indirectly in their own morphological and physiological attributes which enhance their chance of reproduction. Such secondary morphological sex traits may contribute to differences in the burrow architecture of fossorial mammals, such as the Cape dune mole-rat, Bathyergus suillus. Indeed, little is known about the seasonal changes in burrow architecture or differences in burrow configuration may differ between the sexes of subterranean African mole-rats (Bathyergidae). We excavated burrow systems of male and female B. suillus during the summer and the winter to investigate whether male burrow architecture reflected putative mate-seeking behaviour. We consider burrow geometry in response to mating strategies. Male burrow systems explored the environment more efficiently than females. This is presumably because of the increase in associated energetic costs of being a large male. Males produce more mounds indicating territorial behaviour even when it is energetically costly to dispose of soil onto the surface when the soil is less friable during the summer. Overall tunnel dimensions did not differ between the sexes. It appears that a change in season does not affect the geometry of the burrow system or tunnel dimensions in a climatically buffered environment.Key words: burrow structure, seasonality, sexual selection, mate choice, energetics.

Herbivores are major drivers of ecosystem structure, diversity, and function. Resilient ecosystems therefore require viable herbivore populations in a sustainable balance with environmental resource availability. This balance is becoming harder to achieve, with increasingly threatened species reliant on small protected areas in increasingly harsh and unpredictable environments. Arid environments in North Africa exemplify this situation, featuring a biologically distinct species assemblage exposed to extreme and volatile conditions, including habitat loss and climate change-associated threats. Here, we implement an integrated likelihood approach to relate scimitar-horned oryx (Oryx dammah) and dorcas gazelle (Gazella dorcas) density, via dung distance sampling, to habitat, predator, and geographic correlates in Dghoumes National Park, Tunisia. We show how two threatened sympatric ungulates partition resources on the habitat axis, exhibiting nonuniform responses to the same vegetation gradient. Scimitar-horned oryx were positively associated with plant species richness, selecting for vegetated ephemeral watercourses (wadis) dominated by herbaceous cover. Conversely, dorcas gazelle were negatively associated with vegetation density (herbaceous height, litter cover, and herbaceous cover), selecting instead for rocky plains with sparse vegetation. We suggest that adequate plant species richness should be a prerequisite for areas proposed for future ungulate reintroductions in arid and semi-arid environments. This evidence will inform adaptive management of reintroduced ungulates in protected environments, helping managers and planners design sustainable ecosystems and effective conservation programs.

Both active and passive forest restoration schemes are used in degraded landscapes across the world to enhance biodiversity and ecosystem service provision. Restoration is increasingly also being implemented in biodiversity offset schemes as compensation for loss of natural habitat to anthropogenic development. This has raised concerns about the value of replacing old-growth forest with plantations, motivating research on biodiversity recovery as forest stands age. Functional diversity is now advocated as a key metric for restoration success, yet it has received little analytical attention to date. We conducted a meta-analysis of 90 studies that measured differences in species richness for functional groups of fungi, lichens, and beetles between old-growth control and planted or secondary treatment forests in temperate, boreal, and Mediterranean regions. We identified functional-group–specific relationships in the response of species richness to stand age after forest disturbance. Ectomycorrhizal fungi averaged 90 years for recovery to old-growth values (between 45 years and unrecoverable at 95% prediction limits), and epiphytic lichens took 180 years to reach 90% of old-growth values (between 140 years and never for recovery to old-growth values at 95% prediction limits). Non-saproxylic beetle richness, in contrast, decreased as stand age of broadleaved forests increased. The slow recovery by some functional groups essential to ecosystem functioning makes old-growth forest an effectively irreplaceable biodiversity resource that should be exempt from biodiversity offsetting initiatives.ResumenLos esquemas de restauración pasiva y activa de los bosques son utilizados en paisajes degradados en todo el mundo para mejorar el suministro de servicios ambientales y la biodiversidad. La restauración también se implementa cada vez más en los esquemas de compensación de la biodiversidad como retribución de la pérdida del hábitat natural por causa del desarrollo antropogénico. Esto ha causado preocupaciones sobre el valor del reemplazo de los bosques primarios por plantaciones, lo que motiva a la investigación sobre la recuperación de la biodiversidad durante la edad de pie del bosque. La diversidad funcional ahora es propuesta como una clave métrica para el éxito de la restauración, pero ha recibido muy poca atención analítica a la fecha. Realizamos un meta-análisis de 90 estudios que midieron las diferencias en la riqueza de especies para grupos funcionales de hongos, líquenes y escarabajos entre bosques primarios de control y bosques sembrados o de tratamiento secundario en las regiones templadas, boreales y mediterráneas. Identificamos las relaciones específicas de grupos funcionales en la respuesta de la riqueza de especies a la edad de pie después de la perturbación del bosque. Los hongos ectomicorrízicos necesitaron en promedio de 90 años para recuperar sus valores de bosque promedio (entre 45 años e irrecuperables al 95% de los límites de predicción) y los líquenes epífitos necesitaron de 180 años para alcanzar el 90% del valor de bosque primario (entre 140 años y nunca para la recuperación de valores de bosque primario al 95% de los límites de predicción). La riqueza de escarabajos no saproxílicos, al contrario, disminuyó conforme incrementó la edad de pie de los bosques de hojas anchas. La lenta recuperación por parte de algunos grupos funcionales esenciales para los servicios ambientales hace del bosque primario un recurso irremplazable de biodiversidad que debería estar exento de las iniciativas de compensación de la biodiversidad.

As living organisms, planktonic foraminifera are not passive tracers of the environment. Their test geochemistry—arguably the single most important resource for paleoceanographic research—reflects the combined signal of environmental, biological, and preservational processes. For most species, comparisons of test stable isotopic composition within and among taxa provide the primary means for disentangling the relative influences of these different processes. Here we test the foundations of our paleoceanographic interpretations with the first quantitative comparison of the determinants of carbon and oxygen isotopic variation across multiple ocean basins, studies, and species by re-analyzing size-specific data collated from the literature. We find clear evidence of species-specific biological effects (i.e., vital effects), as the intercepts of size-specific carbon and oxygen isotopic compositions differ significantly among species. Trends in body size and isotopic composition, particularly in dinoflagellate bearing taxa, suggest that much of the size-dependent isotopic variation observed in death assemblages (i.e., core tops and sediments) relates to factors influencing the maximum size obtained by adults rather than ontogeny. The presence and type of photosymbiont hosted (dinoflagellate, chrysophyte, or none) were a major factor affecting species- and size-specific ?18O values. In contrast, size-related trends in ?13C values were driven by depth habitat (mixed layer, thermocline, subthermocline), symbiont ecology and whether the assemblage was alive or dead when sampled. On this broad geographic and oceanographic scale, ocean basin and biome had a significant effect on ?18O and ?13C values . Our analysis and its model-averaged predictions provide a quantitative basis for interpreting size-specific isotopic variation in 22 species of modern macroperforate planktonic foraminifera. We conclude by highlighting existing data gaps and outstanding questions of the relative influence of environmental, preservational, and biological processes on variation in the test geochemistry of planktonic foraminifera.

The doubly magic superdeformed band in the N = Z nucleus 60Zn has been identified. Linking transitions connecting this band to the yrast line provide the first spin, parity, and excitation energy measurements for superdeformed states in the A˜60 region. The stretched- E2 character and relatively large B(E2) values of these transitions suggest a nonstatistical decay-out process.