Phylogenetic Signal in Module Composition and Species Connectivity in Compartmentalized Host-Parasite Networks

Bongiovani

et al. 2017

An. Acad. Bras. Ciênc.

The degradation and homogenization of natural habitats is considered a major cause of biotic homogenization. Many studies have been undertaken on the effects of dams on aquatic wildlife, in particular fish assemblages. But how do dams affect the parasitic fauna of such fish? The aim of the present study was to examine parasitic similarity, comparing the diversity and structure of parasite communities of Leporinus friderici (Characiformes, Anostomidae) in three upstream tributaries under the influence of the Jurumirim Dam on the Upper Paranapanema River in southeastern Brazil. The present study did not find any significant differences in parasite communities among populations of L. friderici in the three upstream tributaries. This result highlights that dams promote and facilitate the dispersal of organisms between localities, and therefore the spatial homogenization of parasite communities. Overall, the results suggest that fish parasite assemblages can provide suitable data for evaluating biotic homogenization caused by dams.

contrasting

confidence: 86%

Parasite infracommunities of Leporinus friderici: A comparison of three tributaries of the Jurumirim Reservoir in southeastern Brazil

Bongiovani

et al. 2017

An. Acad. Bras. Ciênc.

“…network size) and the composition/turnover of species and traits (i.e. model parameters) that a community can hold [4,5,30,[51][52][53][54]. Second, extracting the contribution of network size and complexity, the hybrid behavioural rule alone can explain nearly 40% variation of observed modularity.…”

Section: Discussionmentioning

confidence: 99%

A hybrid behavioural rule of adaptation and drift explains the emergent architecture of antagonistic networks

2015

Ecological processes that can realistically account for network architectures are central to our understanding of how species assemble and function in ecosystems. Consumer species are constantly selecting and adjusting which resource species are to be exploited in an antagonistic network. Here we incorporate a hybrid behavioural rule of adaptive interaction switching and random drift into a bipartite network model. Predictions are insensitive to the model parameters and the initial network structures, and agree extremely well with the observed levels of modularity, nestedness and node-degree distributions for 61 real networks. Evolutionary and community assemblage histories only indirectly affect network structure by defining the size and complexity of ecological networks, whereas adaptive interaction switching and random drift carve out the details of network architecture at the faster ecological time scale. The hybrid behavioural rule of both adaptation and drift could well be the key processes for structure emergence in real ecological networks.

The American Naturalist

“…In addition, we also use simulation to explore the properties of previously developed methods that test for host-parasite coevolution effects. We find that when phylogenetic signal in host/parasite specialism-generalism exists or the evolutionary interaction effects exist, the proposed statistics and permutation schemes of Legendre et al (2002), Hommola et al (2009), andKrasnov et al (2012) do indeed result in high Type I error rates. In contrast, the framework that we present can adequately control for these additional effects if they are fitted and is still able to identify the coevolutionary interaction when it exists.…”

mentioning

confidence: 85%

“…Such situations may lead to inflated Type I error rates if the chosen summary statistics depend on patterns generated by these additional processes. In an alternative nonparametric approach, Krasnov et al (2012) used network analysis to assign host and parasite species to modules by maximizing the modularity statistic (Newman and Girvan 2004) developed for unipartite networks (see also Fortuna et al 2010). The correlation between phylogenetic distance and the species co-occurrence index was used to measure phylogenetic signal in community structure.…”

mentioning

confidence: 99%

A Tale of Two Phylogenies: Comparative Analyses of Ecological Interactions

Hadfield

Krasnov

Poulin

et al. 2014

Self Cite

109

157

The evolution of traits involved in ecological interactions such as predator-prey, host-parasite, and plant-pollinator interactions, are likely to be shaped by the phylogenetic history of both parties. We develop generalized linear mixed-effects models (GLMM) that estimate the effect of both parties' phylogenetic history on trait evolution, both in isolation but also in terms of how the two histories interact. Using data on the incidence and abundance of 206 flea species on 121 mammal species, we illustrate our method and compare it to previously used methods for detecting host-parasite coevolution. At large spatial scales we find that the phylogenetic interaction effect was substantial, indicating that related parasite species were more likely to be found on related host species. At smaller spatial scales, and when sampling effort was not controlled for, phylogenetic effects on the number and types of parasite species harbored by hosts were found to dominate. We go on to show that in situations where these additional phylogenetic effects exist, then previous methods have very high Type I error rates when testing for the phylogenetic interaction. Our GLMM method represents a robust and reliable approach to quantify the phylogenetic effects of traits determined by, or defined by, ecological interactions and has the advantage that it can easily be extended and interpreted in a broader context than existing permutation tests.