Visualizing Worldwide Prevalence of Age-Related Dual Sensory Loss.

This study aims to create a first visualization of global prevalence of age-related dual sensory loss (DSL), significantly affecting older people's quality of life. Data from World Health Organization (WHO) regions, particularly African, American, and European, were analyzed. The study focused on DSL onset and prevalence, using adjusted life expectancy for regional comparison.

How effective are maternal effects at having effects?

The well studied trade-off between offspring size and offspring number assumes that offspring fitness increases with increasing per-offspring investment. Where mothers differ genetically or exhibit plastic variation in reproductive effort, there can be variation in per capita investment in offspring, and via this trade-off, variation in fecundity. Variation in per capita investment will affect juvenile performance directly--a classical maternal effect--while variation in fecundity will also affect offspring performance by altering the offsprings' competitive environment.

Talkin' 'bout my generation: environmental variability and cohort effects.

In variable environments, it is probable that environmental conditions in the past can influence demographic performance now. Cohort effects occur when these delayed life-history effects are synchronized among groups of individuals in a population. Here we show how plasticity in density-dependent demographic traits throughout the life cycle can lead to cohort effects and that there can be substantial population dynamic consequences of these effects.