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Although phylogenetic studies have shown covariation between the properties of spider major ampullate (MA) silk and web building, both spider webs and silks are highly plastic so we cannot be sure whether these traits functionally covary or just vary across environments that the spiders occupy. As MaSp2-like proteins provide MA silk with greater extensibility, their presence is considered necessary for spider webs to effectively capture prey. Wolf spiders (Lycosidae) are predominantly non-web building, but a select few species build webs. We accordingly collected MA silk from two web-building and six non-web-building species found in semirural ecosystems in Uruguay to test whether the presence of MaSp2-like proteins (indicated by amino acid composition, silk mechanical properties and silk nanostructures) was associated with web building across the group. The web-building and non-web-building species were from disparate subfamilies so we estimated a genetic phylogeny to perform appropriate comparisons. For all of the properties measured, we found differences between web-building and non-web-building species. A phylogenetic regression model confirmed that web building and not phylogenetic inertia influences silk properties. Our study definitively showed an ecological influence over spider silk properties. We expect that the presence of the MaSp2-like proteins and the subsequent nanostructures improves the mechanical performance of silks within the webs. Our study furthers our understanding of spider web and silk co-evolution and the ecological implications of spider silk properties.

Made available in DSpace on 2018-12-11T17:23:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-01 Protected areas (PAs) are essential for biodiversity conservation, but their coverage is considered inefficient for the preservation of all species. Many species are subdivided into evolutionarily significant units (ESUs) and the effectiveness of PAs in protecting them needs to be investigated. We evaluated the usefulness of the Brazilian PAs network in protecting ESUs of the critically endangered Pithecopus ayeaye through ongoing climate change. This species occurs in a threatened mountaintop ecosystem known as campos rupestres. We used multilocus DNA sequences to delimit geographic clusters, which were further validated as ESUs with a coalescent approach. Ecological niche modeling was used to estimate spatial changes in ESUs' potential distributions, and a gap analysis was carried out to evaluate the effectiveness of the Brazilian PAs network to protect P. ayeaye in the face of climate changes. We tested the niche overlap between ESUs to gain insights for potential management alternatives for the species. Pithecopus ayeaye contains at least three ESUs isolated in distinct mountain regions, and one of them is not protected by any PA. There are no climatic niche differences between the units, and only 4% of the suitable potential area of the species is protected in present and future projections. The current PAs are not effective in preserving the intraspecific diversity of P. ayeaye in its present and future range distributions. The genetic structure of P. ayeaye could represent a typical pattern in campos rupestres endemics, which should be considered for evaluating its conservation status. Programa de Pós-Graduação em Zoologia Instituto de Ciências Biológicas Universidade Federal de Minas Gerais - UFMG Belo Horizonte, Minas Gerais Brasil Programa de Desarrollo Universitario Centro Universitario de Rivera Universidad de la República - UdelaR Rivera Uruguay Laboratório de Herpetologia Departamento de Zoologia Instituto de Biociências de Rio Claro Universidade Estadual Júlio Mesquita Filho - UNESP Rio Claro, São Paulo Brasil Centro de Sensoriamento Remoto Instituto de Geociências Universidade Federal de Minas Gerais - UFMG Belo Horizonte, Minas Gerais Brasil Laboratório de Fauna e Unidades de Conservação Departamento de Engenharia Florestal Faculdade de Tecnologia Universidade de Brasília - UnB Brasília, Distrito Federal Brasil Graduação em Ciências Biológicas Instituto de Ciências Biológicas Universidade Federal de Minas Gerais - UFMG Belo Horizonte, Minas Gerais Brasil Laboratório Sagarana Instituto de Ciências Biológicas e da Saúde Universidade Federal de Viçosa - UFV Florestal, Minas Gerais Brasil

Coalescent-based algorithms coupled with the access to genome-wide data have become powerful tools forassessing questions on recent or rapid diversification, as well as delineating species boundaries in the absence of reciprocal monophyly. In southern South America, the diversification of Liolaemus lizards during the Pleistocene is well documented and has been attributed to the climatic changes that characterized this recent period of time. Past climatic changes had harsh effects at extreme latitudes, including Patagonia, but habitat changes at intermediate latitudes of South America have also been recorded, including expansion of sand fields over northern Patagonia and Pampas). In this work, we apply a coalescent-based approach to study the diversification of the Liolaemus wiegmannii species complex, a morphologically conservative clade that inhabits sandy soils across northwest and south-central Argentina, and the south shores of Uruguay. Using four standard sequence markers (mitochondrial DNA and three nuclear loci) along with ddRADseq data we inferred species limits and a time calibrated species tree for the L. wiegmannii complex in order to evaluate the influence of Quaternary sand expansion/retraction cycles on diversification. We also evaluated the evolutionary independence of the recently described L. gardeli and inferred its phylogenetic position relative to L. wiegmannii. We find strong evidence for six allopatric candidate species within L. wiegmannii, which diversified during the Pleistocene. The Great Patagonian Glaciation (∼1 million years before present) likely split the species complex into two main groups: one composed of lineages associated with sub-Andean sedimentary formations, and the other mostly related to sand fields in the Pampas and northern Patagonia. We hypothesize that early speciation within L. wiegmannii was influenced by the expansion of sand dunes throughout central Argentina and Pampas. Finally, L. gardeli is supported as a distinct lineage nested within the L. wiegmannii complex. Fil: Villamil, Joaquín. Universidad de la República. Facultad de Ciencias; Uruguay Fil: Avila, Luciano Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; Argentina Fil: Morando, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; Argentina Fil: Sites, Jack W.. University Brigham Young; Estados Unidos Fil: Leaché, Adam D.. University of Washington; Estados Unidos Fil: Maneyro, Raúl. Universidad de la República. Facultad de Ciencias; Uruguay Fil: Camargo Bentaberry, Arley. Universidad de la República; Uruguay

Speciation processes have long been inferred from phylogenetic, phylogeographic, and biogeographic pattern-driven perspectives. Now much current speciation research is attempting to more directly describe the underlying processes and mechanisms of divergence leading to speciation. Ideally, researchers should integrate both process- and pattern-based approaches for a more comprehensive understanding of speciation. To this end, a symposium was organized during the 7th World Congress of Herpetology in Canada with the goal of bringing leading experts together to share successful examples of these perspectives and to promote a more cohesive understanding of reptile and amphibian speciation. Here we present a joint paper of short and updated summaries of each of these contributions with the aim of providing a reference source and launching pad for students and researchers interested in speciation in amphibians and reptiles.

Relative to South America's ecoregions, the temperate grasslands of the Pampas have been poorly studied from a phylogeographic perspective. Based on an intermediate biogeographic setting between subtropical forest (Atlantic Forest) and arid ecosystems (Chaco and Patagonia), Pampean species are expected to show unstable demographic histories due to the Quaternary climatic oscillations. Herein, we investigate the phylogenetic relatedness and phylogeographic history of Pseudopaludicola falcipes, a small and common frog that is widely distributed across the Pampean grasslands. First, we use molecular data to assess if P. falcipes represents a single or multiple, separately evolving cryptic lineages. Because P. falcipes is a small-size species (

A decade ago Sites and Marshall [1] described the empirical practice of species delimitation as “a Renaissance issue in systematic biology”. At the time there was an odd disconnect be‐ tween the two frequently stated empirical goals systematic biology: the discovery of: (1) monophyletic groups (clades) and relationships within these at all hierarchical levels above species; and (2) lineages (species); compared to the actual practice of the discipline. While much of systematic biology had been devoted to the first goal, the second goal had until re‐ cently been largely ignored [2], despite the fact that species are routinely used as the basic units of analysis in biogeography, ecology, evolutionary biology, and conservation biology [3,4]. However, Sites and Marshall [1] noted “signs of a Renaissance” at the time of their re‐ view, which was precipitated in part by others emphasizing the need to distinguish between a non-operational, ontological definition of species, versus the empirical (operational) data needed to test their reality [5-7]. De Queiroz [7] (p. 60) noted that “All modern species defi‐ nitions either explicitly or implicitly equate species with segments of population level evolu‐ tionary lineages.” De Queiroz also noted that this was a revised version of Simpson’s “evolutionary species concept”, which defines a species as “a lineage (an ancestraldescend‐ ent sequence of populations) evolving separately from others and with its own evolutionary role and tendencies” ([8], p. 153), and called this a General Lineage Concept (GLC) of species ([7], p. 65). De Queiroz [9] further emphasized that the multiple empirical criteria simply re‐ flect the many contingent properties (differences in genetic or morphological features, adap‐ tive zones or ecological niches, mate-recognition systems, reproductive compatibility, monophyly, etc.) of diverging populations associated with different evolutionary processes operating in various geographic contexts [10,11]. Sites and Marshall [1] noted that the emerging consensus among systematists and evolutionary biologists was based on the utili‐ ty of this distinction (ontological definition vs. empirical species delimitation [SDL] meth‐