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Bell P.R.,University of New England of Australia | Campione N.E.,Uppsala University | Persons W.S.,University of Alberta | Currie P.J.,University of Alberta | And 3 more authors.
Biology Letters | Year: 2017

Recent evidence for feathers in theropods has led to speculations that the largest tyrannosaurids, including Tyrannosaurus rex, were extensively feathered. We describe fossil integument from Tyrannosaurus and other tyrannosaurids (Albertosaurus, Daspletosaurus, Gorgosaurus and Tarbosaurus), confirming that these large-bodied forms possessed scaly, reptilian-like skin. Body size evolution in tyrannosauroids reveals two independent occurrences of gigantism; specifically, the large sizes in Yutyrannus and tyrannosaurids were independently derived. These new findings demonstrate that extensive feather coverings observed in some early tyrannosauroids were lost by the Albian, basal to Tyrannosauridae. This loss is unrelated to palaeoclimate but possibly tied to the evolution of gigantism, although other mechanisms exist. © 2017 The Author(s) Published by the Royal Society.

Quach T.,Texas Southern University | Brooks D.M.,Houston Museum of Natural Science | Miranda H.C.,Texas Southern University
Mitochondrial DNA | Year: 2016

The complete mitochondrial genome of the Palawan peacock-pheasant Polyplectron napoleonis is 16,710 bp and contains 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a controlregion. All protein-coding genes use the standard ATG start codon, except for cox1 which has GTG start codon. Seven out of 13 PCGs have TAA stop codons, two have AGG (cox1 and nd6), and three PCGs (nd2, cox2 and nd4) have incomplete stop codon of just T- - nucleotide. © 2014 Informa UK Ltd.

Miranda Jr. H.C.,Texas Southern University | Brooks D.M.,Houston Museum of Natural Science | Kennedy R.S.,Ma-Maria
Wilson Journal of Ornithology | Year: 2011

We constructed a phylogenetic hypothesis of the pattern of colonization of Philippine scops owls (Otus and Mimizuku). Two mitochondrial genes, ND2 and cytochrome b, were sequenced for 12 samples representing six Philippine endemic taxa: three endemic species, one of which has three endemic subspecies; and one endemic genus. Topology, branch length information, and sequence divergence were used to present the hypothesis for the pattern, direction, and sequence of island colonization events. Philippine scops owls are in two well-supported clades, consistent with at least two independent colonization routes. One route is represented by the montane clade of Otus sunia, O. longicornis, and O. mirus. The other clade is represented by three subspecies of the lowland O. megalotis. The basal position of Mimizuku gurneyi relative to the megalotis clade suggests early colonization of Mindanao. Branch lengths and sequence divergence data are congruent with the morphological differences among the megalotis races. The three races of megalotis differed in 15 of 16 morphological characters. Based on molecular and morphological evidence, we recognize the following Otus megalotis subspecies as full species: Luzon Lowland Scops Owl (O. megalotis), Mindanao Lowland Scops Owl (O. everetti), and Visayan Lowland Scops Owl (O. nigrorum). We also propose reassigning the Giant Scops Owl (Mimizuku gurneyi) to the genus Otus for phyletic consistency. © 2011 by the Wilson Ornithological Society.

News Article | November 30, 2016
Site: www.eurekalert.org

Since the discovery of the fossil dubbed Lucy 42 years ago this month, paleontologists have debated whether the 3 million-year-old human ancestor spent all of her time walking on the ground or instead combined walking with frequent tree climbing. Now, analysis of special CT scans by scientists from The Johns Hopkins University and the University of Texas at Austin suggests the female hominin spent enough time in the trees that evidence of this behavior is preserved in the internal structure of her bones. A description of the research study appears November 30 in the journal PLOS ONE. Analysis of the partial fossilized skeleton, the investigators say, shows that Lucy's upper limbs were heavily built, similar to champion tree-climbing chimpanzees, supporting the idea that she spent time climbing and used her arms to pull herself up. In addition, they say, the fact that her foot was better adapted for bipedal locomotion (upright walking) than grasping may mean that climbing placed additional emphasis on Lucy's ability to pull up with her arms and resulted in more heavily built upper limb bones. Exactly how much time Lucy spent in the trees is difficult to determine, the research team says, but another recent study suggests Lucy died from a fall out of a tall tree. This new study adds to evidence that she may have nested in trees at night to avoid predators, the authors say. An eight-hour slumber would mean she spent one-third of her time up in the trees, and if she also occasionally foraged there, the total percentage of time spent above ground would be even greater. Lucy, housed in the National Museum of Ethiopia, is a 3.18 million-year-old specimen of Australopithecus afarensis -- or southern ape of Afar -- and is among the oldest, most complete fossil skeletons ever found of any adult, erect-walking human ancestor. She was discovered in the Afar region of Ethiopia in 1974 by Arizona State University anthropologist Donald Johanson and graduate student Tom Gray. The new study analyzed CT scan images of her bones for clues to how she used her body during her lifetime. Previous studies suggest she weighed less than 65 pounds and was under 4 feet tall. "We were able to undertake this study thanks to the relative completeness of Lucy's skeleton," says Christopher Ruff, Ph.D., a professor of functional anatomy and evolution at the Johns Hopkins University School of Medicine. "Our analysis required well-preserved upper and lower limb bones from the same individual, something very rare in the fossil record." The research team first had a look at Lucy's bone structure during her U.S. museum tour in 2008, when the fossil was detoured briefly to the High-Resolution X-Ray Computed Tomography Facility in the University of Texas at Austin Jackson School of Geosciences. For 11 days, John Kappelman, Ph.D., anthropology and geological sciences professor, and geological sciences professor Richard Ketcham, Ph.D., both of the University of Texas at Austin, carefully scanned all of her bones to create a digital archive of more than 35,000 CT slices. High-resolution CT scans were necessary because Lucy is so heavily mineralized that conventional CT is not powerful enough to image the internal structure of her bones. "We all love Lucy," Ketcham says, "but we had to face the fact that she is a rock. The time for standard medical CT scanning was 3.18 million years ago. This project required a scanner more suited to her current state." The new study uses CT slices from those 2008 scans to quantify the internal structure of Lucy's right and left humeri (upper arm bones) and left femur (thigh bone). "Our study is grounded in mechanical engineering theory about how objects can facilitate or resist bending," says Ruff, "but our results are intuitive because they depend on the sorts of things that we experience about objects -- including body parts -- in everyday life. If, for example, a tube or drinking straw has a thin wall, it bends easily, whereas a thick wall prevents bending. Bones are built similarly." "It is a well-established fact that the skeleton responds to loads during life, adding bone to resist high forces and subtracting bone when forces are reduced," explains Kappelman. "Tennis players are a nice example: Studies have shown that the cortical bone in the shaft of the racquet arm is more heavily built up than that in the nonracquet arm." A major issue in the debate over Lucy's tree climbing has been how to interpret skeletal features that might be simply "leftovers" from a more primitive ancestor that had relatively long arms, for example. The advantage of the new study, Ruff says, is that it focused on characteristics that reflect actual behavior during life. Lucy's scans were compared with CT scans from a large sample of modern humans, who spend the majority of their time walking on two legs on the ground, and with chimpanzees, a species that spends more of its time in the trees and, when on the ground, usually walks on all four limbs. "Our results show that the upper limbs of chimpanzees are relatively more heavily built because they use their arms for climbing, with the reverse seen in humans, who spend more time walking and have more heavily built lower limbs," says Ruff. "The results for Lucy are convincing and intuitive." Other comparisons carried out in the study suggest that even when Lucy walked upright, she may have done so less efficiently than modern humans, limiting her ability to walk long distances on the ground, Ruff says. In addition, all of her limb bones were found to be very strong relative to her body size, indicating that she had exceptionally strong muscles, more like those of modern chimpanzees than modern humans. A reduction in muscle power later in human evolution may be linked to better technology that reduced the need for physical exertion and the increased metabolic demands of a larger brain, the researchers say. "It may seem unique from our perspective that early hominins like Lucy combined walking on the ground on two legs with a significant amount of tree climbing," says Kappelman, "but Lucy didn't know she was "unique" -- she moved on the ground and climbed in trees, nesting and foraging there, until her life was likely cut short by a fall -- probably out of a tree." Graduate student M. Loring Burgess of the Johns Hopkins University School of Medicine was also an author on the paper. The study was funded by the Paleoanthropology Lab Fund, the University of Texas at Austin College of Liberal Arts and the Houston Museum of Natural Science. The University of Texas High-Resolution X-Ray CT Facility was supported by U.S. National Science Foundation grants EAR-0646848, EAR-0948842 and EAR-1258878. Comparative data were gathered with support from U.S. National Science Foundation grants BCS-0642297 and BCS-1316104.

Siles L.,Texas Tech University | Brooks D.M.,Houston Museum of Natural Science | Aranibar H.,Armonia BirdLife | Tarifa T.,Institute Ecologia Coleccion Boliviana Of Fauna | And 4 more authors.
Journal of Mammalogy | Year: 2013

Although significant work has been done to define species relationships within the Neotropical genus Micronycteris, the group has yet to be fully resolved. In Bolivia Micronycteris is represented by 4 species: M. hirsuta, M. megalotis, M. minuta, and M. sanborni. Through examination of morphological characters and analyses of cranial measurements and genetic data, we determine that M. sanborni is not found in Bolivia and describe a new species closely related to it. The new species is morphometrically distinct from its congeners, forming a cluster separate from M. schmidtorum, M. minuta, and M. brosseti along principal component (PC) 1 (explaining 57.3% of the variation and correlated with maxillary toothrow length) and also separate from M. sanborni along PC 2 (explaining 35.4% of the variation and correlated with condylobasal length). The new species forms a statistically supported clade in all phylogenetic analyses; however, a sister relationship to M. sanborni is not supported. Genetic distance values that separate Micronycteris sp. nov. from its closest relatives range from 5.3% (versus M. sanborni) to 10.4% (versus M. minuta from Guyana). We diagnose and describe the new species in detail and name it in honor of the late Terry Lamon Yates for his contributions to Bolivian mammalogy. Micronycteris sp. nov. is Bolivia's 1st endemic bat species and because of its importance, the conservation implications are discussed. © 2013 American Society of Mammalogists.

Brooks D.M.,Houston Museum of Natural Science
Wilson Journal of Ornithology | Year: 2013

Results are reported from a citizen-science program to study the ecology, behavior, and reproduction of an invasive population of Red-vented Bulbuls (Pycnonotus cafer) in Houston, Texas. The most frequent behaviors are foraging (n = 69), resting (n = 45), and calling (n = 29). The entire population occurred in urban areas. Bulbuls consumed berries (n = 8 species), fruits (n = 5), flowers (n = 5), and buds (n = 4); some insects are also included in the diet. Nine of the 20 species of identified plants consumed are exotics found within the native range of the bulbul, six are exotics found outside the native range, and five are native Texas species. The most common of the 35 species of plants that bulbuls perched in are bamboo (Bambusa sp.), crape myrtle (Lagerstroemia indica), edible fig (Ficus carica), and tallow (Sapium sebiferum). Flock size averaged 2.3 birds/flock (range = 1-22) and the largest flocks (12-22 birds) are in late summer and early winter. Bulbuls are not migrants; peak observations are during spring and summer, with lower numbers during October. General biology is similar between Houston bulbuls, native populations in Asia, and other invasive populations in the Northern Hemisphere. This alien population is not a serious agricultural pest or disperser of weedy seeds, does not compete with native species, and has not expanded beyond the Houston region in the continental United States. © 2013 by the Wilson Ornithological Society.

Brooks D.M.,Houston Museum of Natural Science
Wilson Journal of Ornithology | Year: 2015

Two captive pairs of Little Tinamou (Crypturellus soui) were studied to describe reproduction, development, and associated behaviors of this extremely cryptic forest dwelling species. Pairs were strongly territorial. Precopulatory courtship behaviors were performed by the female. Male tinamous showed strong nest attendance during incubation and sat without leaving the nest from day 14 until the eggs hatched. Nest abandonment and false abandonment occurred due to environmental stress, flushing by humans, eggs being laid in a poor location, and if clutch size was too large. Renewed reproductive efforts began shortly following loss of a previous clutch, with calling activity and inter-clutch duration being a minimum of 3 and 5 days, respectively. © 2015 The Wilson Ornithological Society.

Brooks D.M.,Houston Museum of Natural Science
Wilson Journal of Ornithology | Year: 2012

Results of queries through public avian list-servers and a thorough literature search formed a data base to synthesize patterns of birds trapped in spider webs. Sixty-nine cases of birds, representing 54 species in 23 families, were reported trapped in webs. Hummingbirds were the most diverse family (9 species) and had the most cases of entrapment (n = 20). Archilochus colubris represented the species with the most cases of entrapment (n = 6). Mean mass and wing chord length of all species trapped were 11 g and 61 mm, respectively. Eighty-seven percent of all individuals had mass ≤15 g and 88 had a wing chord <90 mm. Phaethornis longuemareus and Mellisuga minima represented the smallest species (mass = 2 g, wing chord = 37 mm), and Streptopelia senegalensis was the largest (mass = 80 g, wing chord = 138 mm). Thirty cases of birds were entrapped without human intervention: 22 died and eight not wrapped in silk freed themselves. Those wrapped in silk invariably died unless freed by a human observer. One-half of all reported spider webs were of the genus Nephila, and all were orb weavers except for a single Latrodectus. Nephila clavipes entrapped nine species representing 14 cases, ranging from Mellisuga minima (mass = 2 g, wing chord = 37 mm) to Catharus ustulatus (mass = 23 g, wing chord = 93 mm). Patterns, causes, and consequences of birds entrapped in spider webs are discussed, including orb weavers as opportunistic predators of birds trapped in webs, and spider webs as a natural environmental hazard to birds. © 2012 by the Wilson Ornithological Society.

Bouffard L.A.,Yale University | Brooks D.M.,Houston Museum of Natural Science
Journal of Sustainable Forestry | Year: 2014

The white-winged guan (Penelope albipennis, Cracidae), thought extinct until 1979, today numbers <300 individuals. We investigated the role of the guans in seed dispersal and predation dynamics by recording seed germination from fecal samples of wild birds during the dry-season (May-December 2010). This study was conducted at Chaparri Ecological Preserve, in the critically endangered Tumbesian ecosystem on the western slope of the Andes. Field observations show that this bird is a frugivore; Cordia lutea (Boraginaceae) was the primary fruit consumed of the eight species of seeds collected from droppings. Collected seeds were sown in pots under nursery conditions and monitored for germination. Germination rates of passed seeds for Cordia lutea were compared to those that had been collected from a control group of trees. Germination was significantly different between fecal and control seeds, suggesting the plant germinated better after passing through the guans alimentary tract. The identification of flower structures, and digested seeds in feces show that guans can be effective fruit and flower predators. This study provides further information regarding the diet for conservation of the white-winged guan and suggests the bird may aid seed germination in some instances and may act as a predator in others. © 2014 Copyright Taylor and Francis Group, LLC.

News Article | November 7, 2016
Site: www.prweb.com

Joyce Wagner, a retiree from the field of adult education, has completed her new book “My Life as a Honey Bee”: a thorough depiction of all aspects of caring for, researching, and literally being a honey bee. Wagner’s time volunteering at the Houston Museum of Natural Science provided her with a more in-depth look at honey bees. What had begun as a curiosity soon developed into a passion. As her interest and knowledge grew, it became an obsession with delightful results. “After taking copious notes, (I) realized (I) had written a book!” Published by New York City-based Page Publishing, Joyce Wagner’s informative tale provides very detailed scientific information from a unique viewpoint. The use of an actual honey bee as the voice that delivers these facts is effective as it invests genuine interest in a character rather than a species that can be difficult to relate to due to their broadly misunderstood nature. From evidence of the earliest occurrence of the honey bee and its honey’s use in ancient societies to the intricacies of the biologically set caste system of the hive, Wagner describes in great detail everything that is to be known about honey bees. Even more important than its role as an informative resource is this book’s underlying theme of demanding respect for a creature whose endangerment would not only spell the demise of honey bees but of many other important systems in nature and in economics. Readers who wish to experience this un-“bee”-lievably detailed work can purchase “My Life as a Honey Bee” at bookstores everywhere, or online at the Apple iTunes store, Amazon, Google Play or Barnes and Noble. For additional information or media inquiries, contact Page Publishing at 866-315-2708. Page Publishing is a traditional New York based full-service publishing house that handles all of the intricacies involved in publishing its authors’ books, including distribution in the world’s largest retail outlets and royalty generation. Page Publishing knows that authors need to be free to create - not bogged down with complicated business issues like eBook conversion, establishing wholesale accounts, insurance, shipping, taxes and the like. Its roster of authors can leave behind these tedious, complex and time consuming issues, and focus on their passion: writing and creating. Learn more at http://www.pagepublishing.com.

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