Key to predicting impacts of predation is understanding the mechanisms through which predators impact prey populations. While consumptive effects are well-known, non-consumptive predator effects (risk effects) are increasingly being recognized as important. Studies of risk effects, however, have focused largely on how trade-offs between food and safety affect fitness. Less documented, and appre...

According to their main life history traits, organisms can be arranged in a continuum from fast (species with small body size, short lifespan and high fecundity) to slow (species with opposite characteristics). Life history determines the responses of organisms to natural and anthropogenic factors, as slow species are expected to be more sensitive than fast species to perturbations. Owing to th...

Theory predicts that populations of animals with late maturity, low fecundity, large body size and low body growth rates will have low potential rates of population increase at low abundance. If this is true, then these traits may be used to predict the intrinsic rate of increase for species or populations, as well as extinction risks. We used life-history and population data for 63 stocks of c...

Many studies have aimed to identify common predictors of successful introductions of alien species, but the search has had limited success, particularly for animals. Past research focused primarily on mean trait values, even though genetic and phenotypic variation has been shown to play a role in establishment success in plants and some animals (mostly invertebrates). Using a global database de...

This article describes recent trends in annual fertility rates, and generation measurements of average family size and family size distributions for eight selected European Countries. It compares the changing ages at which mothers are having children and the decline in higher order births, both over time and between countries: The way that variations and changes in annual rates influence genera...

Historically, Rocky Mountain National Park (RMNP) has supported a small black bear (Ursus americanus) population of low productivity. Increased visitor use of the park and development around its periphery could lead to a reduction in population viability of RMNP’s bear population or could increase the potential for human–bear conflict. Therefore, we investigated contemporary survival and produc...

The fishery of Lake Victoria became a major commercial fishery with the introduction of Nile perch in 1950s and 1960s. Biological and population characteristics point to a fishery under intense fishing pressure attributed to increased capacity and use of illegal fishing gears. Studies conducted between 1998 to 2000 suggested capture of fish between slot size of 50 to 85 cm TL to sustain the fis...

This paper presents the results of the application of a bit-string model of languages (Schulze and Stauffer 2005) to problems of taxonomic patterns. The questions addressed include the following: (1) Which parameters are minimally needed for the development of a taxonomic dynamics leading to the type of distribution of language family sizes currently attested (as measured in the number of langu...

The total fertility rate of Nigerian women has remained high at 5.7. This is even higher for women in rural areas. Men and women in rural areas desire more children than those in urban areas. This study was aimed at describing and comparing the factors that influence family size decisions among men and women in Bokkos, a rural Local Government Area in Plateau state, Nigeria. A cross sectional d...

Host-parasite interactions are often characterized by large fluctuations in host population size, and we investigated how such host bottlenecks affected coevolution between a bacterium and a virus. Previous theory suggests that host bottlenecks should provide parasites with an evolutionary advantage, but instead we found that phages were rapidly driven to extinction when coevolving with hosts e...