Individuals are predicted to behave more altruistically and less competitively toward their
relatives, because they share a relatively high proportion of their genes (eg, one-half for …

The hypothesis of group selection fell victim to a seemingly devastating critique in 1960s
evolutionary biology. In Unto Others (1998), we argue to the contrary, that group selection is …

Recent decades have witnessed an explosion of theoretical and empirical studies of sex
allocation, transforming how we understand the allocation of resources to male and female …

The use of optimality models in the investigation of adaptation remains controversial. Critics
charge that advocates of the optimality approach assume that the traits they analyze are …

Assumptions about mating structure have been important in the development of sex ratio
theory. Fisher's theory of frequency dependent selection for sex ratio equality, and Charnov's …

Steven Orzack is at the Dept of Ecology and Evolution, University of Chicago, 1101 E. 57th
Street, Chicago, IL 60637, USA; Elliott Sober is at the Philosophy Dept, University of …

The costs and benefits of parasite virulence are analysed in an evolutionarily stable strategy
(ESS) model. Increased host mortality caused by disease (virulence) reduces a parasite's …

Studies of sex allocation offer excellent opportunities for examining the constraints and limits
on adaptation. A major topic of debate within this field concerns the extent to which the …

Sex allocation theory offers excellent opportunities for studying the precision of adaptation.
One of the best-supported areas in the field of sex allocation is Hamilton's theory of local …

Fig-pollinating and fig-parasitizing wasps are integral parts of one of the most fascinating
plant-insect interactions known. Moreover, studies of these wasps have been instrumental in …