The regionalization of the mammalian spinal column is an important evolutionary, developmental, and functional hallmark of the clade. Vertebral column regions are usually defined using transitions in external bone morphology, such as the presence of transverse foraminae or rib facets, or measurements of vertebral shape. Yet the internal structure of vertebrae, specifically the trabecular (spongy) bone, plays an important role in vertebral function, and is subject to the same variety of selective, functional, and developmental...
Climatic refugia and reduced extinction correlate with underdispersion in mammals and birds in AfricaJacob C. Cooper, Nicholas M. A. Crouch, Adam W. Ferguson & John M. Bates
Macroevolutionary patterns, often inferred from metrics of community relatedness, are often used to ascertain major evolutionary processes shaping communities. These patterns have been shown to be informative of biogeographic barriers, of habitat suitability and invasibility (especially with regards to environmental filtering), and of regions that function as evolutionary cradles (i.e., sources of diversification) or museums (i.e., regions of reduced extinction). Here, we analysed continental datasets of mammal and bird distributions to identify primary drivers of...
Genomic data support the taxonomic validity of Middle American livebearers Poeciliopsis gracilis and Poeciliopsis pleurospilus (Cyprinodontiformes: Poeciliidae)Sarah Ward, Caleb McMahan, Basanta Khakurel, April Wright & Kyle Piller
Poeciliopsis (Cyprinodontiformes: Poeciliidae) is a genus comprised of 25 species of freshwater fishes. Several well-known taxonomic uncertainties exist within the genus, especially in relation to the taxonomic status of Poeciliopsis pleurospilus and P. gracilis. However, to date, no studies have been conducted to specifically address the taxonomic status of these two species. The goal of this study was to examine the taxonomic validity of P. pleurospilus and P. gracilis using genomic data (ddRADseq) in phylogenetic,...
Phylogenomics and fossil data inform the systematics and geographic range evolution of a diverse Neotropical ant lineageBenjamin Blanchard, Shauna Price, Scott Powell, Bonnie Blaimer & Corrie Moreau
Recent advances in phylogenomics allow for the use of large amounts of genetic information in phylogenetic inference. Ideally, the increased resolution and accuracy of such inferences facilitate improved understanding of macroevolutionary processes. Here, we integrate ultraconserved elements (UCEs) with fossil and biogeographic range data to explore diversification and geographic range evolution in the diverse turtle ant genus Cephalotes. We focus on the potential role of the uplift of the Panamanian land bridge and the putative...
Giant carnivorous dinosaurs such as Tyrannosaurus rex and abelisaurids are characterized by highly reduced forelimbs that stand in contrast to their huge dimensions, massive skulls, and obligate bipedalism. Another group that follows this pattern, yet is still poorly known, is the Carcharodontosauridae: dominant predators that inhabited most continents during the Early Cretaceous and reached their largest sizes in Aptian-Cenomanian times. Despite many discoveries over the last three decades, aspects of their anatomy, especially with regard...
Demographic rates and stature of tree species in 13 sub-tropical forests: annual growth, annual survival, annual recruitment >( 1 cm dbh), stature (max dbh)Stephan Kambach, Richard Condit, Salomón Aguilar, Helge Bruelheide, Sarayudh Bunyavejchewin, Chia-Hao Chang-Yang, Yu-Yun Chen, George Chuyong, Stuart J. Davies, Sisira Ediriweera, Corneille E. N. Ewango, Edwino S. Fernando, Nimal Gunatilleke, Savitri Gunatilleke, Stephen P Hubbell, Akira Itoh, David Kenfack, Somboon Kiratiprayoon, Yi-Ching Lin, Jean-Remy Makana, Mohizah Bt. Mohamad, Nantachai Pongpattananurak, Rolando Pérez, Lillian Jennifer V. Rodriguez, I-Fang Sun … & Nadja Rüger
Organisms of all species must balance their allocation to growth, survival and recruitment. Among tree species, evolution has resulted in different life-history strategies for partitioning resources to these key demographic processes. Life-history strategies in tropical forests have often been shown to align along a trade-off between fast growth and high survival, i.e. the well-known fast-slow continuum. In addition, an orthogonal trade-off has been proposed between tall stature – resulting from fast growth and high survival...
Early stages of speciation with gene flow in the Amazilia Hummingbird (Amazilis amazilia) subspecies complex of Western South AmericaSarah Cowles, Christopher Witt, Elisa Bonaccorso, Felix Grewe & J. Albert Uy
Disentangling the factors underlying the diversification of geographically variable species with a wide geographical range is essential to understanding the initial stages and drivers of the speciation process. The Amazilia Hummingbird, Amazilis amazilia, is found along the Pacific coast from northern Ecuador down to the Nazca Valley of Peru, and is currently classified as six phenotypically differentiated subspecies. Our aims were to resolve the evolutionary relationships of the six subspecies, to assess the geographical pattern...
Investigations of phenotypic disparity across geography often ignore macroevolutionary processes. As a corollary, the random null expectations to which disparity is compared and interpreted may be unrealistic. We tackle this issue by representing, in geographical space, distinct processes of phenotypic evolution underlying ecological disparity. Under divergent natural selection, assemblages in a given region should have empirical disparity higher than expected under an evolutionarily-oriented null model, while the opposite may indicate constraints on phenotypic evolution. We...
Captive specimens in museum collections facilitate study of rare taxa, but the lifestyles, diets, and lifespans of captive animals differ from their wild counter- parts. Trabecular bone architecture adapts to in vivo forces, and may reflect interspecific variation in ecology and behavior as well as intraspecific variation between captive and wild specimens. We compared trunk vertebrae bone microstructure in captive and wild xenarthran mammals to test the effects of ecology and captivity. We collected μCT...
Field Museum of Natural History9
University of Kansas1
National University of San Luis1
National Sun Yat-sen University1
National Dong Hwa University1
Natural History Museum of Los Angeles County1
UK Centre for Ecology & Hydrology1
George Washington University1