Avian gene trees, landscape evolution, and geology: towards a modern synthesis of Amazonian historical biogeography?

Abstract

ABSTRACT. As the number of phylogeographic studies on Amazonian birds increases, spatially and temporally different scenarios are gradually replacing previous interpretations of Amazonian historical biogeography. At the same time, recent studies have improved significantly our understanding of Amazonian geological history during the late Tertiary and Quaternary, two periods regarded as critical for the recent diversification of the Amazonian avifauna. The notion that geologically older and more stable areas of Amazonia (such as the Brazilian and Guianan shields) functioned as "species-pumps", whereas geologically more dynamic areas (such as the western Amazonian lowlands) mostly "captured" part of the diversity generated nearby, was supported by a recent phylogeographic study focusing on a species complex of the genus Xiphorhynchus (Dendrocolaptidae). Here, I review 14 recent additional molecular datasets to assess whether this historical scenario can be extended to other lineages of Amazonian birds as well. The reviewed datasets indicated, among other things, a clear dichotomy in the diversification histories of species associated with seasonally flooded versus upland forests, and those with high versus low dispersal capabilities. Many "core" lineages of upland species found nowadays in western Amazonia are clearly associated with more basal lineages from the Brazilian shield, Guianan shield, and the Andes, indicating a more recent history in this geologically dynamic region. On the other hand, lineages associated with seasonally flooded forests seem to have an ancient history in western Amazonia, apparently expanding over the geologically more stable areas only recently. Most sister taxa of the reviewed lineages exhibited levels of pairwise sequence divergence consistent with splitting events dating back to a time frame stretching from the late Miocene to the early Pleistocene (late Tertiary and early Quaternary periods), a period when significant physiographic and landscape changes took place in Amazonia. When interpreted together, all reviewed studies provide evidence that geology and landscape evolution are tightly linked with the timing and mode of differentiation of Amazonian birds.

Continuous Miocene, Pliocene and Pleistocene Influences on Mitochondrial Diversification of the Capybara (Hydrochoerus Hydrochoeris; Hydrochoeridae, Rodentia): Incapacity to Determine Exclusive Hypotheses on the Origins of the Amazon and Orinoco Diversity for This Species

“…Thus, marine transgressions could have had a great influence on biotic diversification within the Amazon long after the Miocene. Our data agree quite well with some recent studies which indicate that the wetland system may have persisted until the Late Pliocene or Pleistocene [135,147,148]. Aleixo and Rossetti [149] claimed that the Midwestern Amazon may be the most dynamic area for new colonization, due to a relatively recent reduction of the Amazon Lake and subsequent floodplains in that area.…”

“…If the MNJ estimate with the second mutation rate were accurate, the HRCH should be extremely important in understanding the mitochondrial diversification of the capybaras following the more recent analyses of Amazon stratigraphy and the paleoenvironment [11,147,148,190]. This suggests a much younger, Plio-Pleistocene history for the transition from a lacustrine system in Western Amazon to the current drainage system.…”

The hidden diversity of Coleodactylus amazonicus (Sphaerodactylinae, Gekkota) revealed by molecular data

“…Uncertainties about the estimated divergence times, the biological meaning of the high divergence among some localities (see Discussion below) and even the geographical range of these phylogenetic species leave open many possible explanations about the diversification in the complex. As reported for other taxa (e.g., Aleixo, 2004;Aleixo and Rossetti, 2007;Santos et al, 2009), it is likely that several events had played influential roles in diversification of ''C. amazonicus" in different time scales.…”

Phylogeny and historical biogeography of gnateaters (Passeriformes, Conopophagidae) in the South America forests

“…In our biogeographic inference the ancestral lineage of Conopophaga seems to have its distribution centered on the Brazilian Shield and started to colonize the western Amazonia basin only as the Pebas and Acre wetlands systems were filled with sediment (Figs. 2 and 4) (Aleixo and Rosseti, 2007; and see Latrubesse et al, 2010). Thus, Conopophagidae data add to the general diversification pattern in the Thamnophiloidea, with species-poor clades of relatively restricted geographical distributions, until the fairly recent phylogenetic expansion in the Conopophaga clade (Figs.…”