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Sperm production represents a costly reproductive investment by males. High reproductive competition within the female reproductive tract may select for higher sperm counts or quality resulting in selection for larger testes size. In species where females mate multiply or have more offspring per litter (litter size), or more litters per year (litter rate), male reproductive competition may select for larger relative testes size (i.e., scaled by body mass). Given that different mating systems vary in the alternative forms of reproductive investment available to males, sperm production levels may vary with social system. Here, we examined the relationship between testes size and mating systems, litter size, and litter rate while considering male lifespan and investment in paternal care in 224 terrestrial mammalian species in 15 orders. Relative testes size was larger in species where females mated with multiple males. Furthermore, in species with multiple mating females, species with higher litter rates had larger testes compared to species with fewer litters per year. In contrast, in monogamous species, species that had multiple litters per year had smaller relative testes sizes compared to species with fewer litters per year. Neither longevity nor paternal care influenced testes size. Our results elucidate the effect of female reproductive strategies on relative testes size is nuanced and varies between mating systems. Our findings suggest that the interplay between male reproductive investment and female reproductive investment may be different within similar social mating systems. [ABSTRACT FROM AUTHOR]

Research into single and multiple energy S and Si ion implantation in GaSb grown on GaAs substrates is presented.

The bushmeat trade, or the trade in wild animals for meat, is a primary threat to wildlife and ecosystems in Sulawesi, Indonesia. Hunting for trade and consumption can hasten the local extirpation of vulnerable species, such as fruit bats and the protected babirusa and Sulawesi crested black macaque. This study provides a much‐needed step in understanding the bushmeat trade by describing longitudinal trends in the amount of bushmeat (animal carcasses) observed for sale in markets in North Sulawesi, a particularly biodiversity‐rich area. Surveys were conducted in 10 markets in 2011, 2015, 2018 and 2019. At each market, total counts of all taxa for sale were noted, and encounter rates per market sample were derived to account for variable sampling effort across years and markets. Generalized Linear Mixed Models were used to compare encounter rates across years, months and markets. Our results show that although animal carcasses are still sold in high numbers, there has been an overall decrease between 2011 and 2019, particularly between 2011 and 2018 (encounter rate fell by 99%). However, bats, rats and Sulawesi warty pigs were still present at high levels, indicating a persistent demand for bushmeat in North Sulawesi. The encounter rate of protected taxa for sale was low, but steady throughout the study period. We identified which markets sold the greatest amount of bushmeat to inform future conservation actions and management. Based on our results, the persistent demand for bushmeat in the region, and the continued presence of protected taxa in the markets, we recommend further research to establish the sustainability of the bushmeat trade at its current rate. [ABSTRACT FROM AUTHOR]

The exponential growth of human population and infrastructure is significantly reducing the amount of ecological resources available for wild animals. We analyzed the effect of human activity on Barbary macaques Macaca sylvanus, an endangered species restricted to the fragmented forests of Morocco and Algeria, using location data from five social groups inhabiting Ifrane National Park, Morocco. We used a resource selection function to explore the effects of anthropogenic disturbance on macaque habitat selection, using nine natural, social, and anthropogenic disturbance variables as predictors. Forest cover, home range overlap, herding route proximity, and road proximity were all significant predictors of habitat use. Macaques avoided areas used by local shepherds, to reduce the risk of attack by shepherds' dogs, but approached roads to increase the chances of provisioning by tourists. However, herding route and road use varied seasonally in line with levels of human use, suggesting that macaques may be navigating their environment strategically (in space and time) to balance food acquisition and risk avoidance. The results of this study highlight the importance of assessing human impact on habitat selection in both space and time. Our data on seasonal variations in macaques' use of roads can help prevent road injuries, a major source of mortality for provisioned macaques, by focusing management efforts by national park workers in time and space. Furthermore, understanding when and where macaques seek provisioning from tourists can help combat provisioning, which negatively impacts macaque health, behavior, and susceptibility to poaching. [ABSTRACT FROM AUTHOR]

Presents a study that investigated magneto-transport and cyclotron resonance of two-dimensional electron gas in silicon under a magnetic field. Details of the experiments; Results and discussion.