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Abstract In female vertebrates, the pelvis plays a role in important biological processes including reproduction and locomotion, and its evolution is thus likely influenced by multiple selective pressures. Here, we used CT scans, 3D geometric morphometrics, and phylogenetic comparative methods to describe the evolution of the female pelvis ofSceloporuslizards, and to tease apart the relative importance of the evolution of live‐bearing, arboreality, and allometry in altering pelvis shape. We found that the ancestral egg‐laying species tended to exhibit dorsoventrally tall female pelvises, and that two of three clades of live‐bearingSceloporusevolved both larger body sizes and dorsoventrally flat, laterally wide female pelvises. Larger body sizes may have relaxed constraints on pelvis height, allowing these mostly terrestrial and rock‐dwelling species to respond to selective forces that enhance crypsis or thermoregulation by evolving dorsoventrally flatter and laterally wider pelvises. In contrast, one large clade of live‐bearing and arboreal species had dorsoventrally tall pelvises, like those of the ancestral egg‐laying species. Again, evolutionary shifts to larger body sizes may have relaxed allometric constraints, allowing adaptive responses to arboreality that converge on those of terrestrial egg‐layers. Further studies are needed in other taxa to determine the importance of larger body sizes and consequently relaxed allometric constraints in shaping other morphological features. 

ABSTRACT The vertebrate skull is a complex structure, and studies of skull shape have yielded considerable insight into the evolutionary forces shaping specialized phenotypes in organisms as diverse as bats, frogs, and fossorial animals. Here, we used phylogenetic comparative analyses of CT scans of male skulls from 57 species ofSceloporuslizards to explore patterns of skull evolution in a group of generalist taxa. We found that most interspecific variation is in terms of skull elongation such that some species have long, narrow skulls, whereas others exhibit more compact and robust skulls. We also found strong links to overall body size, with evolutionary shifts to larger bodies being associated with more compact skulls and slower evolutionary rates. This is the opposite of the pattern in most mammals in which larger bodied species have longer snouts, and more like the pattern in frogs in which function has played a more important evolutionary role. Also, unlike other vertebrates, the jaw, anterior, and posterior parts of theSceloporusskull are largely integrated, having evolved independently of each other only to a limited, albeit significant, degree. Our results emphasize the importance of body size in the evolutionary shaping of the skull and suggest that additional studies of behavioral function in a generalist group are warranted. 

Abstract Understanding how changes in climate affect habitat availability for species through time is critical for macroevolutionary, ecological, and conservation research. When combined with palaeoclimate reconstructions, the fossil record provides insights into how species' geographic distributions have responded to past climate shifts, including under non‐analogous climate conditions. Palaeophylogeographic models (PPGMs) offer a framework to integrate modern and palaeontological data into phylogenetic comparative analyses of species climate tolerances. TheppgmR package is an implementation of PPGMs, which estimates species climate envelopes, reconstructs ancestral climatic tolerances across phylogenies, and projects these onto palaeoclimatic maps to identify climatically available regions through time. The package also supports direct inclusion of fossil occurrences with associated palaeoclimatic data, allowing a reconstruction of past trends of species climate tolerances projected into palaeoclimatic maps to pinpoint the locations of climate availability through time according to the fossil record. We demonstrate the broad applicability ofppgmthrough detailed case studies, showing its potential for addressing research questions in macroevolutionary and conservation palaeobiology research. Theppgmpackage complements existing R packages by allowing researchers to use analytical techniques on large integrated datasets and facilitates reproducible analyses of species climate niches over deep and shallow time. 

Abstract Despite playing a critical role in evolutionary processes and outcomes, relatively little is known about rates of recombination in the vast majority of species, including squamate reptiles—the second largest order of extant vertebrates, many species of which serve as important model organisms in evolutionary and ecological studies. This paucity of data has resulted in limited resolution on questions related to the causes and consequences of rate variation between species and populations, the determinants of within-genome rate variation, as well as the general tempo of recombination rate evolution on this branch of the tree of life. In order to address these questions, it is thus necessary to begin broadening our phylogenetic sampling. We here provide the first fine-scale recombination maps for two species of spiny lizards, Sceloporus jarrovii and Sceloporus megalepidurus, which diverged at least 12 Mya. As might be expected from similarities in karyotype, population-scaled recombination landscapes are largely conserved on the broad-scale. At the same time, considerable variation exists at the fine-scale, highlighting the importance of incorporating species-specific recombination maps in future population genomic studies. 

Abstract The actual incorporation of dopant species into the ZnS Quantum Dots (QDs) host lattice will induce structural defects evidenced by a red shift in the corresponding exciton. The doping should create new intermediate energetic levels between the valence and conduction bands of the ZnS and affect the electron-hole recombination. These trap states would favour the energy transfer processes involved with the generation of cytotoxic radicals, so-called Reactive Oxygen Species, opening the possibility to apply these nanomaterials in cancer research. Any synthesis approach should consider the direct formation of the QDs in biocompatible medium. Accordingly, the present work addresses the microwave-assisted aqueous synthesis of pure and doped ZnS QDs. As-synthesized quantum dots were fully characterized on a structural, morphological and optical viewpoint. UV-Vis analyzes evidenced the excitonic peaks at approximately 310 nm, 314 nm and 315 nm for ZnS, Cu-ZnS and Mn-ZnS, respectively, Cu/Zn and Mn/Zn molar ratio was 0.05%. This indicates the actual incorporation of the dopant species into the host lattice. In addition, the Photoluminescence spectrum of non-doped ZnS nanoparticles showed a high emission peak that was red shifted when Mn 2+ or Cu 2+ were added during the synthesis process. The main emission peak of non-doped ZnS, Cu-doped ZnS and Mn-doped ZnS were observed at 438 nm, 487 nm and 521 nm, respectively. Forthcoming work will address the capacity of pure and Cu-, Mn-ZnS quantum dots to generate cytotoxic Reactive Oxygen Species for cancer treatment applications.