No preference in female sika deer for conspecific over heterospecific male sexual calls in a mate choice context

Mating signals can be used both in contexts of species recognition and mate quality assessment. This study examines species recognition abilities in oestrous females presented with male mating calls from both conspecifics and closely related allopatric heterospecifics. Red deer and sika deer are naturally allopatric polygynous species capable of hybridization during sympatry. Male mating calls are sexually selected and differ greatly between species. Previous work indicated that most but not all oestrous red deer hinds prefer male mating calls from conspecifics over heterospecific sika deer. Using two-speaker playback experiments, we extend this examination by measuring the preference responses of oestrous sika deer hinds to these stimuli. We predicted that oestrous sika deer hinds will show little flexibility in behavioural responses and prefer conspecific calls over heterospecific calls, similar to those of red deer hinds. In contrast, sika deer hinds showed high levels of flexibility and no difference in overall preference behaviours, suggesting that vocal behaviour does not provide a solid barrier to hybridization in this species. The asymmetry in heterospecific preference responses between these species is discussed in relation to possible causation and hybridization patterns observed in free-ranging populations

Do red deer hinds prefer stags that produce harsh roars in mate choice contexts?

Red deer stags give two types of roars during the breeding season, termed ‘common’ and ‘harsh’ roars. This study tested the hypothesis that the characteristic spectro-temporal structure of male harsh roars functions to directly attract females towards male callers during the breeding season. The results show that oestrous hinds look for longer towards speakers broadcasting sequences containing harsh roars, but do not preferentially approach or spend more time in close proximity to speakers broadcasting harsh roars over those broadcasting only common roars. While these observations confirm that the specific acoustic structure of male harsh roars functions to draw the attention of hinds, they are not consistent with the notion that these calls have an immediate impact on mate choice decisions by stimulating oestrous hinds to move towards male callers. Consequently, we suggest that intersexual selection through female mate choice is unlikely to be a major factor driving the evolution of male red deer harsh roars

Local community engagement as a practice: an investigation of local community engagement issues and their impact on transport megaprojects' social value

Purpose: Transport megaprojects often struggle to offer social value (SV) that meets local communities' needs. This problem is embedded in how local communities' views are captured and incorporated into SV plans through local community engagement (LCE). By problematising the literature, this article aims to identify LCE issues and their impacts on SV plans at the front-end of transport megaprojects. Design/methodology/approach: The theoretical lens of the study is the practice theory developed by Schatzki (2016, 2005). The authors conceptualised LCE as a practice and conducted 32 semi-structured interviews with UK practitioners. The authors collected data in three steps from three types of practitioners involved in LCE practice and SV planning: project managers, LCE experts and SV experts. Findings: The authors identified 18 LCE issues with thematic analysis and clustered them into five themes. These issues impact LCE with five mechanisms. Findings show that a weak link between LCE and SV plans due to the issues reduces LCE to a tick-box exercise and presents a distorted view of local communities. This reduces SV plans to the bare minimum for project approval instead of offering relevant SV to local communities. Addressing the issues goes beyond changing the approach of project teams to engagement (from instrumental to normative) and requires changing the practices. Originality/value: For the first time, the study uses practice theory to conceptualise LCE as a practice, following the notion of project as practice. The study problematises the literature to address the under-represented link between LCE and SV plans

Modern Slavery in Projects: A Systematic Literature Review and Research Agenda

It is estimated that 40.3 million individuals are victims of modern slavery, including those exploited in projects. In project studies, there are growing research streams on topics, such as ethics, sustainability and fairness, yet modern slavery is vastly ignored. This article presents a systematic literature review on modern slavery. After summarizing the main forms and consequences of modern slavery, it focuses on construction projects explaining the structural conditions making construction projects prone to modern slavery, the kafala system, and what can be done to address modern slavery. Lastly, the article introduces propositions, a research agenda, and implications for practice

Temperature dependence of surface stress across an order-disorder transition: p(1x2)O/W(110)

Strain relaxations of a p(1x2) ordered oxygen layer on W(110) are measured as a function of temperature across the disordering transition using low-energy electron diffraction. The measured strains approach values of 0.027 in the [1-10] and -0.053 in the [001] direction. On the basis of the measured strain relaxations, we give quantitative information on temperature-dependent surface stress using the results of ab initio calculations. From the surface formation energy for different strains, determined by first-principles calculations, we estimate that surface stress changes from -1.1 for the ordered phase to -0.2N/m for the disordered one along [1-10], and from 5.1 to 3.4 N/m along [001]. Moreover, our observation that the strains scale inversely with domain size confirms that the strain relaxation takes place at the domain boundaries.Comment: 8 pages, 5 figure

Physical properties of the jet from DG Tauri on sub-arcsecond scales with HST/STIS

We derive the physical properties at the base of the jet from DG Tau both along and across the flow and as a function of velocity. We analysed seven optical spectra of the DG Tau jet, taken with the Hubble Space Telescope Imaging Spectrograph. The spectra were obtained by placing a long-slit parallel to the jet axis and stepping it across the jet width. The resulting position-velocity diagrams in optical forbidden emission lines allowed access to plasma conditions via calculation of emission line ratios. We find at the base of the jet high electron density, $n_e \sim$ 10$^5$, and very low ionisation, $x_e \sim 0.02-0.05$, which combine to give a total density up to $n_H \sim$ 3 10$^6$. This analysis confirms previous reports of variations in plasma parameters along the jet, (i.e. decrease in density by several orders of magnitude, increase of $x_e$ from 0.05 to a plateau at 0.7 downstream at 2$''$ from the star). Furthermore, a spatial coincidence is revealed between sharp gradients in the total density and supersonic velocity jumps. This strongly suggests that the emission is caused by shock excitation. The position-velocity diagrams indicate the presence of both fast accelerating gas and slower, less collimated material. We derive the mass outflow rate, $\dot{M}_j$, in the blue-shifted lobe in different velocity channels, that contribute to a total of $\dot{M}_j \sim$ 8 $\pm$ 4 10$^{-9}$ M$_\odot$ yr$^{-1}$. We estimate that a symmetric bipolar jet would transport at the low and intermediate velocities probed by rotation measurements, an angular momentum flux of $\dot{L}_j \sim$ 2.9 $\pm$ 1.5 10$^{-6}$ M$_\odot$ yr$^{-1}$ AU km s$^{-1}$. The derived properties of the DG Tau jet are demonstrated to be consistent with magneto-centrifugal theory. However, non-stationary modelling is required in order to explain all of the features revealed at high resolution.Comment: 16 pages, 18 figure

Interação de micorriza vesicular-arbuscular com leguminosas em solos ácidos.

Este trabalho apresenta uma abordagem para MVA e acidez do solo; Simbiose MVA ? Rhizobium-leguminosa; Dependência de MVA e Micorrizas e pesquisa na região amazônica.bitstream/item/60903/1/Doc55-micorrizaarbuscular.pd