purpose the present study was designed to evaluate the effects of aerobic and strength training on cardiac variables such as blood pressure, heart rate (hr), and metabolic parameters like cholesterol, high density lipoprotein (hdl), triglycerides and anthropometric parameters of obese women of punjab. methods this study was performed as an experimental study, in which subjects were randomly sel...

In 1963-1964 W. D. Hamilton introduced the concept of inclusive fitness, the only significant elaboration of Darwinian fitness since the nineteenth century. I discuss the origin of the modern fitness concept, providing context for Hamilton's discovery of inclusive fitness in relation to the puzzle of altruism. While fitness conceptually originates with Darwin, the term itself stems from Spencer...

It is well known that (1) natural selection typically favors an allele with both a large mean fitness and a small variance in fitness; and (2) investors typically prefer a portfolio with both a large mean return and a small variance in returns. In the case of investors, this mean-variance trade-off reflects risk aversion; in the case of evolution, the mathematics is straightforward but the resu...

The question of how cooperative groups can evolve and be maintained is fundamental to understanding the evolution of social behaviour in general, and the major transitions in particular. Here, we show how selection on an individual trait for group size preference can increase variance in fitness at the group-level, thereby leading to an increase in cooperation through stronger group selection. ...

Metabolic rate reflects the 'pace of life' in every organism. Metabolic rate is related to an organism's capacity for essential maintenance, growth and reproduction-all of which interact to affect fitness. Although thousands of measurements of metabolic rate have been made, the microevolutionary forces that shape metabolic rate remain poorly resolved. The relationship between metabolic rate and...

Large numbers of hatchery salmon spawn in wild populations each year. Hatchery fish with multiple generations of hatchery ancestry often have heritably lower reproductive success than wild fish and may reduce the fitness of an entire population. Whether this reduced fitness also occurs for hatchery fish created with local- and predominantly wild-origin parents remains controversial. Here, we re...

We use digital evolution to study the division of labor among heterogeneous organisms under multiple levels of selection. Although division of labor is practiced by many social organisms, the labor roles are typically associated with different individual fitness effects. This fitness variation raises the question of why an individual organism would select a less desirable role. For this study, ...

Recent hypotheses argue that phylogenetic relatedness should predict both the niche differences that stabilise coexistence and the average fitness differences that drive competitive dominance. These still largely untested predictions complicate Darwin's hypothesis that more closely related species less easily coexist, and challenge the use of community phylogenetic patterns to infer competition...