Health systems have entered a third era embracing whole systems thinking and posing complex policy and management challenges. Understanding how such systems work and agreeing what needs to be put in place to enable them to undergo effective and sustainable change are more pressing issues than ever for policy-makers. The theory-policy-practice-gap and its four dimensions, as articulated by Chini...

Four steps through which parasitic intracellular symbionts could bring about the evolution of two sexes are considered. In the first step, a primitive host population has biparental cytoplasmic inheritance and lacks gametic differentiation: parasitic cytoplasmic elements readily invade and spread by vertical transmission through such host populations, even if they have major deleterious effects...

What does it mean to be “human”? The question, though it has occupied some of the greatest Western minds of philosophy, science, history, and political theory, could not have been answered with any plausibility until recently, for we have only begin to acquire the scientific knowledge necessary to provide an informed response. At the same time, recent scientific and technological developments h...