RESUMEN
Birds harbor a diverse group of haemosporidian parasites that reproduce and develop in the host blood cells, muscle tissue, and various organs, which can cause negative effects on the survival and reproduction of their avian hosts. Characterization of the diversity, distribution, host specificity, prevalence patterns, and phylogenetic relationships of these parasites is critical to the study of avian host-parasite ecology and evolution and for understanding and preventing epidemics in wild bird populations. Here, we tested whether muscle and liver samples collected as part of standard ornithological museum expeditions can be examined to study the diversity and distributions of haemosporidians in the same way as blood collected from individual birds that are typically banded and released. We used a standard molecular diagnostic screening method for mitochondrial DNA (cytochrome b) of the parasites and found that blood, muscle, and liver collected from the same host individual provide similar estimates of prevalence and diversity of haemosporidians from the genera Parahaemoproteus and Leucocytozoon. Although we found higher prevalence for the genus Plasmodium when we screened blood vs. liver and muscle samples, the estimates of the diversity of Plasmodium from different tissue types are not affected at the community level. Given these results, we conclude that for several reasons existing museum genetic resources collections are valuable data sources for the study of haemosporidians. First, ornithological museum collections around the world house tens of thousands of vouchered tissue samples collected from remote regions of the world. Second, the host specimens are vouchered and thus host identification and phenotype are permanently documented in databased archives with a diversity of associated ancillary data. Thus, not only can identifications be confirmed but also a diversity of morphological measurements and data can be measured and accessed for these host specimens in perpetuity.
Asunto(s)
Enfermedades de las Aves/parasitología , Haemosporida/aislamiento & purificación , Infecciones Protozoarias en Animales/parasitología , Animales , Biodiversidad , Aves , Sangre/parasitología , Haemosporida/clasificación , Hígado/parasitología , Músculos/parasitología , MuseosRESUMEN
Phylogenetic relationships and patterns of evolution within Melanerpes, one of the most diverse groups of New World woodpeckers (22-23 lineages), have been complicated due to complex plumages and morphological adaptations. In an attempt to resolve these issues, we obtained sequence data from four nuclear introns and two mitochondrial protein-coding genes for 22 of the 24 currently recognized species in the genus. We performed phylogenetic analyses involving Maximum Likelihood and Bayesian Inference, species-tree divergence dating, and biogeographic reconstructions. Tree topologies from the concatenated and species-tree analyses of the mtDNA and nDNA showed broadly similar patterns, with three relatively well-supported groups apparent: (a) the Sphyrapicus clade (four species); (b) the typical Melanerpes clade, which includes temperate and subtropical dry forest black-backed species; and (c) the mostly barred-backed species, here referred to as the "Centurus" clade. The phylogenetic position of Melanerpes superciliaris regarding the rest of Melanerpes is ambiguous as it is recovered as sister to the rest of Melanerpes or as sister to a group including Sphyrapicus+Melanerpes. Our species tree estimations recovered the same well-delimited highly-supported clades. Geographic range evolution (estimated in BioGeoBEARS) was best explained by a DIVALIKE+j model, which includes vicariance, founder effect speciation, and anagenetic dispersal (range expansion) as important processes involved in the diversification of the largest radiation of woodpeckers in the New World.