Parentage analyses suggest female promiscuity and a disadvantage for athletic males in the colour-polymorphic lizard Podarcis melisellensis

Although laboratory measurements of whole-animal performance have become a standard tool in evolutionary biology, if and how interindividual variation in performance translates into differential fitness remains poorly understood. Particularly rare are studies that have connected performance to mating and reproductive success in the field. In this study, we use DNA microsatellite parentage analyses to study the fitness gradient in a colour-polymorphic lizard, Podarcis melisellensis. We report on two surprising findings. First, contrary to our expectations, individual sprint speed and bite force capacity correlated negatively, not positively, with male mating and reproductive success. Second, we found an unexpected degree of promiscuity in females. Also, contrary to traditional parental investment theory, the variation in mating success and reproductive success was as high in females as in males. Our results call for a better integration of whole-animal performance and life history traits, and for a reconsideration of the ideas on the likeliness of sexual selection acting on female phenotypes.     

Top-down control inhibits spatial self-organization of a patterned landscape

Regular, self-organized spatial patterns in primary producers have been described in a wide range of ecosystems and are predicted to affect community production and resilience. Although consumers are abundant in most systems, the effect of trophic interactions on pattern formation in primary producers remains unstudied. We studied the effects of top-down control by herbivores on a self-organized landscape of regularly spaced, diatom-covered hummocks alternating with water-filled hollows on an intertidal mudflat in The Netherlands. Spatial patterns developed during spring but were followed by a rapid collapse in summer, leading to a flat landscape with low diatom densities and little variation in sediment bed level. This dramatic decline co-occurred with a gradual increase of benthic herbivores. A manipulative field experiment, where benthic herbivores were removed from the sediment, revealed that both diatom growth and hummock formation were inhibited by the activity of benthic herbivores. Our study provides clear evidence of top-down control of spatial self-organized patterns by benthic herbivores within a biological-geomorphic landscape.     

Vocalizations by Alaskan moose: female incitation of male aggression

Evidence of female fomentation of male–male aggression as a mechanism of mate choice is rare, especially in mammals. Female choice of mates in polygynous species may be masked by intense male competition or by males attempting to restrict female choice. We studied protest moans of female Alaskan moose Alces alces gigas in interior Alaska, USA, from 1987 to 1990, to determine if moans incited male–male aggression. Alaskan moose exhibit a mating system in which one dominant male (the harem master) herds, defends, courts, and attempts to mate with females in his harem. Protest moans were given by females only in response to courtship. We hypothesized that if protest moans were related to females reducing harassment and exercising mate choice, females should give protest moans more frequently when courted by small males and less often when courted by large males, and that rates of male–male aggression would be elevated following protest moans. Harems were composed of one large male, with a mean of 4.4 females (median = 3 females); 10% of 132 harems included ≥10 females. The temporal pattern of protest moans from late August through November was associated with, but tended to lag behind, mating behavior. The rate of protest moans given by females decreased with increasing size of males courting them. Male–male aggression was significantly less during periods without protest moans than during periods in which protest moans occurred. These results indicate that female moose gave protest moans to reduce harassment by smaller males, and assure a mating opportunity with the most dominant male. Such a subtle mechanism of indirect mate choice by females may occur in other vertebrates in which choice is limited by a mating system in which male–male combat and male dominance over females reduces opportunities for female choice. The importance of female choice may be undervalued in studies of sexual selection in mammals.     

Sampling approaches to predict urban street noise levels using fixed and temporary microphones

Requirements for static (prediction of L(den) and diurnal averaged noise pattern) and dynamic (prediction of 15 min and 60 min evolution of L(Aeq) and statistical levels L(A90,)L(A50) and L(A10)) noise level monitoring are investigated in this paper. Noise levels are measured for 72 consecutive days at 5 neighboring streets in an inner-city noise measurement network in Gent, Flanders, Belgium. We present a method to make predictions based on a fixed monitoring station, combined with short-term sampling at temporary stations. It is shown that relying on a fixed station improves the estimation of L(den) at other locations, and allows for the reduction of the number of samples needed and their duration; L(den) is estimated with an error that does not exceed 1.5 dB(A) to 3.4 dB(A) according to the location, for 90% of the 3 × 15 min samples. Also the diurnal averaged noise pattern can be estimated with a good accuracy in this way. It was shown that there is an optimal location for the fixed station which can be found by short-term measurements only. Short-term level predictions were shown to be more difficult; 7 day samples were needed to build models able to estimate the evolution of L(Aeq,60min) with a RMSE ranging between 1.4 dB(A) and 3.7 dB(A). These higher values can be explained by the very pronounced short-term variations appearing in typical streets, which are not correlated between locations. On the other hand, moderately accurate predictions can be achieved, even based on short-term sampling (a 3 × 15 minute sampling duration seems to be sufficient for many of the accuracy goals set related to static and dynamic monitoring). Finally, the method proposed also allows for the prediction of the evolution of statistical indicators.     

On the ability of consumer electronics microphones for environmental noise monitoring

The massive production of microphones for consumer electronics, and the shift from dedicated processing hardware to PC-based systems, opens the way to build affordable, extensive noise measurement networks. Applications include e.g. noise limit and urban soundscape monitoring, and validation of calculated noise maps. Microphones are the critical components of such a network. Therefore, in a first step, some basic characteristics of 8 microphones, distributed over a wide range of price classes, were measured in a standardized way in an anechoic chamber. In a next step, a thorough evaluation was made of the ability of these microphones to be used for environmental noise monitoring. This was done during a continuous, half-year lasting outdoor experiment, characterized by a wide variety of meteorological conditions. While some microphones failed during the course of this test, it was shown that it is possible to identify cheap microphones that highly correlate to the reference microphone during the full test period. When the deviations are expressed in total A-weighted (road traffic) noise levels, values of less than 1 dBA are obtained, in excess to the deviation amongst reference microphones themselves.     

Scaled-up bioconversion of fish waste to liquid fertilizer using a 5 L ribbon-type reactor

A scaled-up conversion process of fish waste to liquid fertilizer was performed in a 5 L ribbon-type reactor. Biodegradation was performed by inoculation of autoclaved fish waste with 5.84 × 10(5) CFU mL(-1) of mixed microorganisms for 96 h. As a result, the pH changed from 6.92 to 5.72, the cell number reached 7.28 × 10(5) CFU mL(-1), and approximately 430 g (28.3%) of fish waste was degraded. Analyses indicated that the 96 h culture of inoculated fish waste possessed comparable fertilizing ability to commercial fertilizers in hydroponic culture with amino acid contents of 6.91 g 100 g(-1). Therefore, the scaled-up production achieved a more satisfactory fish waste degradation rate (3.61 g h(-1)) than the flask-scale production (0.24 g h(-1)). The biodegraded broth of fish waste at room temperature did not undergo putrefaction for 6 months due to the addition of 1% lactate.     

Green synthesis of ZrO2 nanoparticles and nanocomposites for biomedical and environmental applications: a review

Environmental Chemistry Letters - Pollution and diseases such as the coronavirus pandemic (COVID-19) are major issues that may be solved partly by nanotechnology. Here we review the synthesis of...     

Main and added effects of heatwaves on hospitalizations for mental and behavioral disorders in a tropical megacity of Vietnam

Environmental Science and Pollution Research - Vietnam is highly vulnerable to climate change-related extreme weather events such as heatwaves. This study assesses the association between heatwaves...     

Evaluation of bio-aerosols type,density, and modeling of dispersion in inside and outside of different wards of educational hospital

Environmental Science and Pollution Research - Exposure to bioaerosols in the air of hospitals is associated with a wide range of adverse health effects due to the presence of airborne...