Interactions involving several parasite species (multi-parasitized hosts) or several host
species (multi-host parasites) are the rule in nature. Only a few studies have investigated …

Bacteria and phages have traditionally been viewed as 'antagonists'. However, temperate
phages can transfer genes, which can broaden their bacterial hosts' metabolic repertoire …

Microbes are widely recognized to be vital to host health. This new consensus rests, in part,
on experiments showing how hosts malfunction when microbes are removed. More and …

According to the stress gradient hypothesis (SGH), ecological interactions between
organisms shift positively as environmental stress increases. In the case of associational …

It has been hypothesized that plant–virus interactions vary between antagonism and
conditional mutualism according to environmental conditions. This hypothesis is based on …

Victims of infection are expected to suffer increasingly as parasite population growth
increases. Yet, under some conditions, faster-growing parasites do not appear to cause …

Highlights•Plant viruses are not always pathogenic to their hosts.•Plant virus pathogenesis is
modulated by the environment.•Plant viruses may be conditional mutualists in some …

Though viruses have generally been characterized by their pathogenic and more generally
harmful effects, many examples of mutualistic viruses exist. Here I explain how the idea of …

The frequency and strength of biotic interactions are thought to be shaped by environmental
conditions. In this study, we reviewed and discussed the potential effects of toxic chemicals …

The fitness effects of symbionts on their hosts can be context-dependent, with usually benign
symbionts causing detrimental effects when their hosts are stressed, or typically parasitic …