Core design principles for nurturing organization-level selection.

Dynamic relationships between individuals and groups have been a focus for evolutionary theorists and modelers for decades. Among evolutionists, selfish gene theory promotes reductionist approaches while multilevel selection theory encourages a context-sensitive approach that appreciates that individuals and groups can both matter. Among economists, a comparable contrast is found wherein the reductionist shareholder primacy theory most associated with Nobel laureate Milton Friedman is very different from the context-sensitive focus on managing common resources that Nobel laureate Elinor Ostrom pioneered. In this article, we examine whether the core design principles that Ostrom advanced can cultivate selection at supra-individual levels across different domains. We show that Ostrom's design principles that were forged in the context of managing natural resources are associated with positive outcomes for human social groups across a variety of functional domains.

Early nutritional stress impairs development of a song-control brain region in both male and female juvenile song sparrows (Melospiza melodia) at the onset of song learning.

Birdsong is a sexually selected trait and is often viewed as an indicator of male quality. The developmental stress hypothesis proposes a model by which song could be an indicator; the time during early development, when birds learn complex songs and/or local variants of song, is of rapid development and nutritional stress. Birds that cope best with this stress may better learn to produce the most effective songs. The developmental stress hypothesis predicts that early food restriction should impair development of song-control brain regions at the onset of song learning. We examined the effect of food restriction on song-control brain regions in fledgling (both sexes, 23-26 days old) song sparrows (Melospiza melodia). Food restriction selectively reduced HVC volume in both sexes. In addition, sex differences were evident in all three song-control regions. This study lends further support to a growing body of literature documenting a variety of behavioural, physiological and neural detriments in several songbird species resulting from early developmental stress.