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- Fecchio, Alan, et al.
(författare)
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Global drivers of avian haemosporidian infections vary across zoogeographical regions
- 2021
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Ingår i: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 30:12, s. 2393-2406
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Tidskriftsartikel (refereegranskat)abstract
- Aim: Macroecological analyses provide valuable insights into factors that influence how parasites are distributed across space and among hosts. Amid large uncertainties that arise when generalizing from local and regional findings, hierarchical approaches applied to global datasets are required to determine whether drivers of parasite infection patterns vary across scales. We assessed global patterns of haemosporidian infections across a broad diversity of avian host clades and zoogeographical realms to depict hotspots of prevalence and to identify possible underlying drivers. Location: Global. Time period: 1994–2019. Major taxa studied: Avian haemosporidian parasites (genera Plasmodium, Haemoproteus, Leucocytozoon and Parahaemoproteus). Methods: We amalgamated infection data from 53,669 individual birds representing 2,445 species world-wide. Spatio-phylogenetic hierarchical Bayesian models were built to disentangle potential landscape, climatic and biotic drivers of infection probability while accounting for spatial context and avian host phylogenetic relationships. Results: Idiosyncratic responses of the three most common haemosporidian genera to climate, habitat, host relatedness and host ecological traits indicated marked variation in host infection rates from local to global scales. Notably, host ecological drivers, such as migration distance for Plasmodium and Parahaemoproteus, exhibited predominantly varying or even opposite effects on infection rates across regions, whereas climatic effects on infection rates were more consistent across realms. Moreover, infections in some low-prevalence realms were disproportionately concentrated in a few local hotspots, suggesting that regional-scale variation in habitat and microclimate might influence transmission, in addition to global drivers. Main conclusions: Our hierarchical global analysis supports regional-scale findings showing the synergistic effects of landscape, climate and host ecological traits on parasite transmission for a cosmopolitan and diverse group of avian parasites. Our results underscore the need to account for such interactions, in addition to possible variation in drivers across regions, to produce the robust inference required to predict changes in infection risk under future scenarios.
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| 2. |
- Ricklefs, Robert E, et al.
(författare)
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Avian migration and the distribution of malaria parasites in New World passerine birds
- 2017
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Ingår i: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 44:5, s. 1113-1123
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Tidskriftsartikel (refereegranskat)abstract
- Aim: Migrating birds transport their parasites, often over long distances, but little is known about the transfer of these parasites to resident hosts in either the wintering or breeding ranges of the migratory host populations. We investigated the haemosporidian parasite faunas of migratory and resident birds to determine connections among distant parasite faunas, plausibly brought about by migratory host populations. Location: Samples were obtained, primarily during or shortly after the local breeding season, throughout the Americas, from the United States through the Caribbean Basin and into northern South America. Methods: Infections were identified by PCR and sequencing of parasite DNA in avian blood samples. The analyses were based on c. 4700 infections representing 79 parasite lineages of Plasmodium and Haemoproteus spp. Geographical connections of lineages between regions in the Americas were compared to those in the Euro-African migration system, where migration distances are longer for many host species and the migrant and resident avifaunas in the wintering areas are phylogenetically more divergent. Results: Haemosporidian lineages exhibited considerable variation in distribution in the Americas, and patterns of distribution differ markedly between the Americas and the Euro-African migration system. In particular, few lineages were recovered from resident species in both temperate and tropical latitudes, particularly in the Euro-African system, in which a large proportion of lineages were restricted to migrants. Parasite lineages in the Euro-African system exhibited considerable phylogenetic conservatism in their distributions, that is, a tendency of related lineages to exhibit similar geographical distributions. In contrast, clades of parasites in the Americas displayed more geographical diversity, with four of 12 clades exhibiting all four of the distribution types representing the combinations of resident and migrant host species in both temperate and tropical latitudes. Main conclusions: Long-distance migrants connect communities of avian haemosporidian parasites in breeding and wintering areas with disparate avifaunas and different vector communities. The degree of parasite lineage sharing between migrants and residents in breeding and wintering areas appears to reflect, to a large degree, the taxonomic similarity of migrants to the resident species in both areas.
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