Habitat Association Predicts Genetic Diversity and Population Divergence in Amazonian Birds

Abstract

The ecological traits of organisms may predict their genetic diversity and population genetic structure and mediate the action of evolutionary processes important for speciation and adaptation. Making these ecological-evolutionary links is difficult because it requires comparable genetic estimates from many species with differing ecologies. In Amazonian birds, habitat association is an important component of ecological diversity. Here, we examine the link between habitat association and genetic parameters using 20 pairs of closely related Amazonian bird species in which one member of the pair occurs primarily in forest edge and floodplains and the other occurs in upland forest interior. We use standardized geographic sampling and data from 2,416 genomic markers to estimate genetic diversity, population genetic structure, and statistics reflecting demographic and evolutionary processes. We find that species of upland forest have greater genetic diversity and divergence across the landscape as well as signatures of older histories and less gene flow than floodplain species. Our results reveal that species ecology in the form of habitat association is an important predictor of genetic diversity and population divergence and suggest that differences in diversity between floodplain and upland avifaunas in the Amazon may be driven by differences in the demographic and evolutionary processes at work in the two habitats.

Contrasting evolutionary histories in Neotropical birds: Divergence across an environmental barrier in South America

“…Previous studies have emphasized the role of biological attributes in the idiosyncratic responses of different species to shared environmental changes, even between codistributed taxa (Garg et al, ; Prates, Rivera, Rodrigues, & Carnaval, ; Prates, Xue et al, ; Smith et al, ). It has been shown that differences in habitat choice and ecological constraints can explain variation in the levels of population divergence across taxa (Burney & Brumfield, ; Garg et al, ; Harvey et al, ; Smith et al, ; Weir, Bermingham, & Schluter, ). In particular, this has been linked to differential dispersal abilities: forest specialists and understorey birds have poor dispersal abilities (Moore, Robinson, Lovette, & Robinson, ) and are less likely to move across a barrier, while habitat generalists, canopy birds and species that inhabit open environments show a higher dispersal propensity.…”

“…Recent comparative studies show that phylogeographical patterns shared among codistributed taxa divided by the same barrier cannot be explained only by a common vicariant event (Brumfield, 2012;Naka & Brumfield, 2018;Oswald et al, 2017;Smith et al, 2014). Instead, evolutionary histories are idiosyncratic and depend largely on the biological attributes of species, such as ecology and dispersal ability, resulting in different and asynchronous responses to a shared evolutionary driver (Burney & Brumfield, 2009;Garg, Chattopadhyay, Wilton, Malia Prawiradilaga, & Rheindt, 2018;Harvey, Aleixo, Ribas, & Brumfield, 2017;Smith et al, 2014).…”

Pervasive admixture between eucalypt species has consequences for conservation and assisted migration

“…With the advent of modern DNA genotyping techniques, studies investigating thousands of genetic markers from across the genome are becoming more common (Gaughran et al, 2018;Hand et al, 2015;Harvey, Aleixo, Ribas, & Brumfield, 2017;Hudson, Freeman, Myburg, Potts, & Vaillancourt, 2015), and several studies have investigated patterns of nuclear genetic structure and gene flow across large geographic regions (Hecht, Matala, Hess, & Narum, 2015;Hendricks et al, 2017;Sampson et al, 2018;Shriver et al, 2005). Studies such as these provide critical information for the conservation of populations with unique genetic heritage, identification of areas of adaptive potential for assisted migration and location of source populations or historical refugia (Hecht et al, 2015;Supple et al, 2018).…”

Divergent mitochondrial lineages arose within a large, panmictic population of the Savannah sparrow (Passerculus sandwichensis)

“…Resistance to population contraction and fragmentation during the Pleistocene in Savannah sparrows is consistent with several hypotheses that link ecological and life history attributes to patterns of population genetic differentiation. First, certain habitat associations can influence patterns of genetic structure with species that occupy more open and/or ephemeral habitats exhibiting less genetic structure than forest/closed habitat species (e.g., Burney & Brumfield, ; Drovetski, Zink, Ericson, & Fadeev, ; Harvey, Aleixo, Ribas, & Brumfield, ). One hypothesis explaining this pattern is that open country taxa exhibit increased dispersal propensity to exploit ephemeral or patchy resources (e.g., Burney & Brumfield, ).…”