Can the host phylogeny (Chiroptera) influence the community of ectoparasite flies (Diptera)?

Abstract

For the phylogeny, the parasites are expected to explore phylogenetically closer hosts because of their greater similarities (Krasnov et al. 2014). Considering that phylogenetic proximity may represent ecological, behavioural, and similar immunological defense among the nearest hosts, the parasite could have lower energy expenditure in the process of adaptation to hosts with similar immune defense (Poulin and Mouillot 2004). However, in contrast to previous studies with other vertebrate groups (Krasnov et al. 2005; Krasnov et al. 2010), in this study, phylogenetically closer hosts showed no similarity in the composition of the ectoparasite community. The absence of an observed relationship may be associated with the high specificity of the parasites, since 65.6% of the analyzed parasites were considered monoxenes, that is, they occurred in only one host species. Generally, the specificity may explain the changes found in the parasite communities, and sometimes the parasite distribution pattern tends to vary according to its host specificity (Poulin et al. 2011). This specificity is considered indicative of ancient evolutionary history and congruent phylogenies between the parasite and host species and may be the result of an adaptation among these, where the parasites would have a low survival capacity in an unusual host (Dick and Gettinger 2005). The degree of specificity may vary widely between parasite species, where some parasites being highly specific (monoxenes) and others highly opportunistic (polixenes). However, opportunistic parasites tend to vary their abundance in the different hosts, being higher in the main host (Poulin and Mouillot 2004). For other groups of parasites, the use of distant hosts may be common (Krasnov et al. 2012). This association may occur due to the lack of host-specific defensive behaviors, such as the immune response. Immune defenses would be more similar between phylogenetically close hosts (Poulin and Mouillot 2004) and may make it more advantageous to parasitize a distant host whose immune defense against such a parasite would not be as effective (Krasnov et al. 2007). Another aspect that could influence this association is the occurrence of a particular host in that region where, in the absence of the main host, it could be replaced by a secondary host. Therefore, a parasite can be considered specific on a local and opportunistic scale on a larger scale broad (Krasnov et al. 2010). The absence of a relationship between the composition of the ectoparasite community and host phylogeny suggests that the structure of the parasite community is being influenced by other factors not analyzed here, such as environmental characteristics, age, reproductive stage, type of shelter of the host, and mobility of the parasite. Thus, to better understand such interactions, it is necessary to analyses both the ecological aspects and the evolutionary history between parasite–host that may be acting on the parasite composition.