Influence of host diet and phylogeny on parasite sharing by fish in a diverse tropical floodplain

Abstract

The patterns of parasite sharing among hosts have important implications for ecosystem structure and functioning, and are influenced by several ecological and evolutionary factors associated with both hosts and parasites. Here we evaluated the influence of fish diet and phylogenetic relatedness on the pattern of infection by parasites with contrasting life history strategies in a freshwater ecosystem of key ecological importance in South America. The studied network of interactions included 52 fish species, which consumed 58 food types and were infected with 303 parasite taxa. Our results show that both diet and evolutionary history of hosts significantly explained parasite sharing; phylogenetically close fish species and/or species sharing food types tend to share more parasites. However, the effect of diet was observed only for endoparasites in contrast to ectoparasites. These results are consistent with the different life history strategies and selective pressures imposed on these groups: endoparasites are in general acquired via ingestion by their intermediate hosts, whereas ectoparasites actively seek and attach to the gills, body surface or nostrils of its sole host, thus not depending directly on its feeding habits.

Uncertain links in host–parasite networks: lessons for parasite transmission in a multi-host system

“…The fast greedy algorithm does not identify the small clusters, but clearly groups equids separately from ruminants. The number of parasites shared by pairs of hosts was negatively correlated with phylogenetic distance, which is congruous with previous research [75–77]. This correlation was strongest in the observed data and was lower in predicted models as no assumptions were included in the model that would predict host–parasite information based on phylogeny.…”

Infectious disease macroecology: parasite diversity and dynamics across the globe

“…Pfenning-Butterworth et al [86] investigated whether host and parasite evolutionary history both affect association patterns between helminth parasites and their mammalian hosts. While a number of studies have shown that host phylogeny plays an important role in shaping the patterns of parasite sharing among host species [72,73,87,88], the relative importance of host versus parasite phylogeny is unclear, largely owing to the lack of robust phylogenetic reconstructions for most groups of parasitic organisms. Using a newly developed phylogenetic model for approximately 250 species of mammalian helminths, combined with comprehensive datasets of host phylogeny and host-parasite associations, they demonstrate that host phylogenetic distances have a larger influence on host-parasite association than those of parasites.…”

Diversity and similarity of the parasites in Megalechis thoracata and Callichthys callichthys (Pisces: Callichthyidae) from Brazilian Amazon

“…Studies of the relationship between fish and their environment are more valuable when they also incorporate host-parasite interactions, as the ecology of parasites and their hosts is one of the most relevant biological factors in these relationships, owing to continuous interactions between fish and their parasites in the environment. As such, in recent years, there has been an increase in interest about the ecological interactions between different fish species, parasites and the environment (Alarcos & Timi, 2012;Alcântara & Tavares-Dias, 2015;Guidelli et al, 2006;Lima et al, 2016;Muñoz et al, 2006;Pantoja et al, 2016;Poulin & Fitzgerald, 1987;Tavares & Luque, 2008;Tavares-Dias et al, 2014).…”

“…Populations of ecologically similar and genetically or evolutionarily related fish species that inhabit the same environment (sympatry) are more likely to have similar community composition of parasites (Alarcos & Timi, 2012;Guidelli et al, 2003;Lima et al, 2016;Muñoz et al, 2006;Pantoja et al, 2016;Poulin & Fitzgerald, 1987;Tavares & Luque, 2008). However, parasite communities are highly complex and dynamic ecological systems, resulting from interactions between different biotic (age, sex, immunity, size, genetics, migration, ecology, reproduction, physiology, etc.)…”

“…(Alarcos & Timi, 2012;Alcântara & Tavares-Dias, 2015;Guidelli et al, 2003;Lima et al, 2016;Pantoja et al, 2016;Poulin & Fitzgerald, 1987;Tavares & Luque, 2008;Tavares-Dias et al, 2014). The influence of these factors can be magnified by the diet of fish; so, hosts with similar diets tend to have an increased probability of infection by similar endoparasites (Alarcos & Timi, 2012;Alcântara & Tavares-Dias, 2015;Lima et al, 2016;Muñoz et al, 2006;Pantoja et al, 2016). This raises the question: Does the overlap in habitat and lifestyle of C. callichthys and M. thoracata in the Amazon River system lead to the occurrence of similar parasite communities in both host species?…”