Semipalmated sandpiper (Calidris pusilla) migration to the Southern Hemisphere includes a 5-day non-stop flight over the Atlantic Ocean, whereas semipalmated plover (Charadrius semipalmatus) migration, to the same area, is largely over land, with stopovers for feeding and rest. We compared the number and 3D morphology of hippocampal astrocytes of Ch. semipalmatus before and after autumnal migration with those of C. pusilla to test the hypothesis that the contrasting migratory flights of these species could differentially shape hippocampal astrocyte number and morphology.We captured individuals from both species in the Bay of Fundy (Canada) and in the coastal region of Bragança (Brazil) and processed their brains for selective GFAP immunolabeling of astrocytes. Hierarchical cluster analysis of astrocyte morphological features distinguished two families of morphological phenotypes, named type I and type II, which were differentially affected after migratory flights. Stereological counts of hippocampal astrocytes demonstrated that the number of astrocytes decreased significantly in C. pusilla, but did not change in Ch. semipalmatus. In addition, C. pusilla and Ch. semipalmatus hippocampal astrocyte morphological features were differentially affected after autumnal migration. We evaluated whether astrocyte morphometric variables were influenced by phylogenetic differences between C. pusilla and Ch. semipalmatus, using phylogenetically independent contrast approach, and phylogenetic trees generated by nuclear and mitochondrial markers. Our findings

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We used molecular tools and a multilocus approach to investigate the phylogeography of Lepidothrix coronata across most of its ample range. We sequenced six DNA fragments to produce phylogenies, molecular dating estimates, analyses of the dynamics of the demographic history of the species and a biogeographic analysis to estimate the events and changes in the ancestral distribution of the species. The results indicated the presence of four well‐established lineages, with high levels of divergence. These lineages are delineated by well‐defined geographic barriers, with one lineage, restricted to the west of the Andes, being the first to diverge from the complex. The other three lineages are exclusive to the Amazonian distribution of the species, with two being found north of the Amazon River, and the third, south of the Amazon. Some of the relationships found between these lineages were distinct from those described in previous studies. Important disagreements were found between the mtDNA phylogeny and that of the multilocus analysis, in relation to the lineages located to the west of the Andes. We propose that past introgression events may have influenced shifts in the relationships between lineages, despite the fact that the groups were well defined in both the phylogenies. The biogeographic analysis indicates that the lineages arose through successive vicariance events, which had a primary role in the diversification of the group. Two or three genetically structured subclades were also found within each Amazonian lineage, although these subclades are not isolated by an obvious geographic barrier.