Why is it that some parasites cause high levels of host damage (ie virulence) whereas others
are relatively benign? There are now numerous reviews of virulence evolution in the …

Most species have one or more natural enemies, eg, predators, parasites, pathogens, and
herbivores, among others. These species in turn typically attack multiple victim species. This …

Infections that consist of multiple parasite strains or species are common in the wild and are
a major public health concern. Theory suggests that these infections have a key influence on …

In many biological examples of cooperation, individuals that cooperate cannot benefit from
the resulting public good. This is especially clear in cases of self-destructive cooperation …

For most, the mere mention of lice forces an immediate hand to the head and recollection of
childhood experiences with nits, medicated shampoos, and traumatic haircuts. But for a …

Humans are changing the environmental conditions of our planet, and animal immune
functions are being affected by these modifications. For instance, a diversity of chemical …

The evolution of drug-resistant pathogens is a major challenge for 21st century medicine.
Drug use practices vigorously advocated as resistance management tools by professional …

Infections frequently contain multiple strains (genotypes) of the same pathogen, yet they are
still usually treated as uniform entities. In this Review, we discuss problems with inconsistent …

Competition between parasite species or strains within hosts is a major evolutionary force in
infections. In response, parasites exhibit a diverse array of strategies that improve their …

Adult coho salmon O ncorhynchus kisutch return each autumn to freshwater spawning
habitats throughout western N orth A merica. The migration coincides with increasing …