We show that the Adomian decomposition method, the time–series expansion, the homotopy–perturbation method, and the variational– iteration method completely fail to provide a reasonable description of the dynamics of the simplest prey–predator system. In is well known that a reasonable description of the dynamics of a nonlinear system by means of a perturbation method is a difficult enterprize ...

A procedure is proposed by which recruit numbers and parental biomass of shrimps stocks can be derived, given a series of catch-per-effort data and estimates of a few ancillary variables. In the Gulf of Thailand, shrimp recruitment decreased with decreasing egg production, but increased with decreasing total (mainly fish) standing stock. The net result of these counteracting effects was an over...

Cities experience significant, near random walk productivity shocks, yet population is slow to adjust. In practise local population changes are dominated by variation in net migration, and we argue that understanding gross migration is essential to quantify how net migration may slow population adjustments. Housing is also a natural candidate for slowing population adjustments because it is dif...

The prehistoric populations of humans are an important source of information to analyze some aspects of the modern human societies. Thinking about the human ancestors it is important because it is possible to understand some of the characteristics of humans nowadays. For instance, human behavior or languages structures are some of the elements that could be studied by looking to human evolution...

Aim There is mounting concern that climate change will lead to the collapse of cyclic population dynamics, yet the influence of climate variability on population cycling remains poorly understood. We hypothesized that variability in survival and fecundity, driven by climate variability at different points in the life cycle, scales up from local populations to drive regional characteristics of p...

Evidence for synchronous fluctuations of spatially separated populations is ubiquitous in the literature, including accounts within and across taxa. Among the few mechanisms explaining this phenomenon is the Moran effect, whereby independent populations are synchronized by spatially correlated environmental disturbances. The body of research on the Moran effect predominantly assumes that enviro...

The determination of whether purse seine fishing in the Eastern Tropical Pacific is hampering the recovery of the northeastern offshore spotted dolphin and eastern spinner dolphin populations is a difficult problem. The question was not answered satisfactorily by a simple consideration of population abundance estimates, despite these estimates being made using innovative methods and great care ...

Ethnic minorities, such as Latinx people of Hispanic or Latino origin, and women earn fewer engineering degrees than Caucasians and men. With shifting population dynamics and high demands for a technically qualified workforce, it is important to achieve broad participation in the engineering workforce by all ethnicities and both genders. Previous research has examined the knowledge of and inter...