Specific Hypotheses on the Geographic Mosaic of Coevolution

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. abstract: Coevolution is one of the major processes organizing the earth's biodiversity. The need to understand coevolution as an ongoing process has grown as ecological concerns have risen over the dynamics of rapidly changing biological communities, the conservation of genetic diversity, and the population biology of diseases. The biggest current challenge is to understand how coevolution operates across broad geographic landscapes, linking local ecological processes with phylogeographic patterns. The geographic mosaic theory of coevolution provides a framework for asking how coevolution continually reshapes interactions across different spatial and temporal scales. It produces specific hypotheses on how geographically structured coevolution differs from coevolution at the local scale. It also provides a framework for understanding how local maladaptation can result from coevolution and why coevolved interactions may rarely produce long lists of coevolved traits that become fixed within species. Long-term field studies of the same interaction across multiple communities and spatially structured mathematical models are together beginning to show that coevolution may be a more important ongoing process than had been indicated by earlier empirical and theoretical studies lacking a geographic perspective.

Geography and host biogeography matter for understanding the phylogeography of a parasite

“…In contrast, other phylogeographic breaks shared by Heligmosomoides and A. sylvaticus in South Western Europe do not correspond to phylogeographic breaks typically found in many other taxa: i.e., the differentiation of Sicily from continental Italy (even if few studies showed that Sicily is a hotspot of biodiversity in Europe (Randi et al, 2003;Fineschi et al, 2005;Fritz et al, 2005)), and the differentiation of Maghreb populations from Spain. These shared specific phylogeographic breaks are, in contrast to usual phylogeographic fractures, good clues arguing for long-term co-differentiation between the two species (Thompson, 2005). Third, this study confirmed that co-differentiation was significantly more likely than independent history between A. sylvaticus and Heligmosomoides in south Western Europe (TREEMAP analyses, Fig.…”

Testing for local host–parasite adaptation: an experiment with Gyrodactylus ectoparasites and guppy hosts

“…Another set of potential reasons for varied results in local hostparasite adaptation studies is untested interactions with other factors related to evolutionary history or ecological context (Thompson, 1994(Thompson, , 1999Morgan et al, 2005). Evolutionarily, different host lineages and their co-evolved parasites could have had different histories of selection, genetic bottlenecks, drift and founder events which might have strongly shaped co-evolutionary trajectories.…”

Higher gregarine parasitism often in sibling species of host damselflies with smaller geographical distributions

“…In four species of damselflies parasitized by a generalist ectoparasite, Yourth et al (2001) concluded that temporal and spatial variation in abundance did not fully explain interspecific variation in immune response. However, immune response T A geographic range increases, the more parasite species it should encounter, which leads to that host species evolving stronger generalised immune responses (Thompson 2005). This could lead to observations where the more widespread and locally abundant host species are less parasitized.…”