Habitat shifts in the evolutionary history of a Neotropical flycatcher lineage from forest and open landscapes

<p>Abstract</p> <p>Background</p> <p>Little is known about the role ecological shifts play in the evolution of Neotropical radiations that have colonized a variety of environments. We here examine habitat shifts in the evolutionary history of <it>Elaenia </it>flycatchers, a Neotropical bird lineage that lives in a range of forest and open habitats. We evaluate phylogenetic relationships within the genus based on mitochondrial and nuclear DNA sequence data, and then employ parsimony-based and Bayesian methods to reconstruct preferences for a number of habitat types and migratory behaviour throughout the evolutionary history of the genus. Using a molecular clock approach, we date the most important habitat shifts.</p> <p>Results</p> <p>Our analyses resolve phylogenetic relationships among <it>Elaenia </it>species and confirm several species associations predicted by morphology while furnishing support for other taxon placements that are in conflict with traditional classification, such as the elevation of various <it>Elaenia </it>taxa to species level. While savannah specialism is restricted to one basal clade within the genus, montane forest was invaded from open habitat only on a limited number of occasions. Riparian growth may have been favoured early on in the evolution of the main <it>Elaenia </it>clade and subsequently been deserted on several occasions. Austral long-distance migratory behaviour evolved on several occasions.</p> <p>Conclusion</p> <p>Ancestral reconstructions of habitat preferences reveal pronounced differences not only in the timing of the emergence of certain habitat preferences, but also in the frequency of habitat shifts. The early origin of savannah specialism in <it>Elaenia </it>highlights the importance of this habitat in Neotropical Pliocene and late Miocene biogeography. While forest in old mountain ranges such as the Tepuis and the Brazilian Shield was colonized early on, the most important colonization event of montane forest was in conjunction with Pliocene Andean uplift. Riparian habitats may have played an important role in facilitating habitat shifts by birds expanding up the mountains along streams and adapting to newly emerging montane forest habitat.</p

Rampant polyphyly indicates cryptic diversity in a clade of Neotropical flycatchers (Aves: Tyrannidae)

Polyphyletic arrangements in DNA phylogenies are often indicators of cryptic species diversity masked by erroneous taxonomic treatments that are frequently based on morphological data. Although mitochondrial (mt)DNA polyphyly is detected relatively rarely in phylogenetic studies, it has recently been found in a variety of tyrant-flycatcher (Tyrannidae) groups. In the present study, we provide a DNA phylogeny for a mitochondrial and a nuclear locus with a complete species sampling in Zimmerius flycatchers, showing that the genus is characterized by multiple mtDNA polyphyly. Based on phylogenetic and life-history information, we suggest the elevation of a number of taxa to species status, leading to a doubling of Zimmerius species-level diversity compared to taxonomic treatments conducted before 2001. © 2013 The Linnean Society of London

NEW AND SIGNIFICANT ISLAND RECORDS, RANGE EXTENSIONS AND ELEVATIONAL EXTENSIONS OF BIRDS IN EASTERN SULAWESI, ITS NEARBY SATELLITES, AND TERNATE

The Wallacean Region continues to be widely unexplored even in such relatively well-known animal groups as birds (Aves). We report on the results of an ornithological expedition from late Nov 2013 through early Jan 2014 to eastern Sulawesi and a number of satellite islands (Togian, Peleng, Taliabu) as well as Ternate. The expedition targeted and succeeded with the collection of 7–10 bird taxa previously documented by us and other researchers but still undescribed to science. In this contribution, we provide details on numerous first records of bird species outside their previously known geographic or elevational ranges observed or otherwise recorded during this expedition. We also document what appears to be a genuinely new taxon, possibly at the species level of kingfisher from Sulawesi that has been overlooked by previous ornithologists. Our results underscore our fragmentary knowledge of the composition of the avifauna of eastern Indonesia, and demonstrate that there continues to be a high degree of cryptic, undescribed avian diversity on these islands more than a century and a half after they were visited by Alfred Russel Wallace and other collectors

Genetic Introgression: An Integral but neglected component of speciation in birds

HYBRIDIZATION, OR THE act of reproduction between different species, is common in birds (Grant and Grant 1992) and can be an agent of adaptive evolution (Veen et al. 2001). When hybridization occurs, a species' genetic material may enter the gene pool of another and thereby introduce genetic novelty. This process is called “genetic introgression” (hereafter “introgression”; Anderson 1949). Although known for decades, the incidence of introgression in nature has long been underappreciated (e.g., Currat et al. 2008). Only recently have evolutionists come to regard it as an important and pervasive mechanism in speciation, in the maintenance of genetic diversity and in the introduction of advantageous novelty into the gene pool (Arnold et al. 1999, Noor et al. 2000, Seehausen 2004). In fact, genetic data now suggest that our own species may have undergone a complicated history of introgression with at least two extinct hominine lineages (Green et al. 2010, Reich et al. 2010). Another reason why introgression is an important topic is the impact of human-induced climate change, which is rapidly shifting vegetation boundaries and creating new hybrid zones, with little-known consequences for the genetic integrity of species (Mank et al. 2004, Brumfield 2010). There has been a tremendous increase in introgressionrelated avian research since a comprehensive overview of the introgression complex between the Blue-winged Warbler (Vermivora cyanoptera) and the Golden-winged Warbler (V. chrysoptera) appeared in The Auk five years ago (Confer 2006). Here, we seek to fill a gap by summarizing the most important recent advances in avian introgression research and our current understanding of locus-specific differences in introgression dynamics, the detection of introgression, its directionality, and its relevance to conservation, phylogenetics, and speciation research.Organismic and Evolutionary Biolog

Genome-wide data reveal cryptic diversity and genetic introgression in an Oriental cynopterine fruit bat radiation

Sampling details consisting of information about number of individuals typed for each marker. Populations with mutiple sampling points are represented by one representative coordinate. FA = forearm length, EL = ear length and TIB = tibia length. All morphological measurements are recorded in millimeters (mm). (XLSX 13 kb