Figure 1.

Examples of how host extinction can impact parasite specificity. Each shape represents a hypothetical parasite species, with their positions reflecting interactions with hosts alongside the host phylogeny. Each extinction scenario involves the loss of one host species (depicted by grey dashed lines). Depending on the original set of host–parasite interactions, the extinction of a host species may result in the loss of a single-host parasite, an example of coextinction (a), the reclassification of a former generalist to a single-host parasite (b), or more subtle changes in which the average phylogenetic distances among hosts may decrease (c) or increase (d) among the remaining hosts. (Online version in colour.)