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Oliver P.M.,South Australian Museum | Oliver P.M.,University of Adelaide | Couper P.,Vertebrate Zoology | Amey A.,Vertebrate Zoology
Zootaxa | Year: 2010

Based on a combination of morphological and genetic data, geographically isolated populations of Pygopus from north-eastern Queensland, formerly referred to Pygopus lepidopodus (Lacépède), are herein described as a new species. Pygopus robertsi sp. nov. can be diagnosed from its congeners by a suite of scalation characters, including fewer keeled dorsal scales, presence of a single continuous row of supracilaries and a lower number of midbody scale rows. It is also deeply divergent genetically from samples of Pygopus lepidopodus from southern Australia. The known distribution of Pygopus robertsi sp. nov. is similar to that of a number of taxa centred upon relatively dry ecotonal habitats at the western edge of the rainforest blocks of north-eastern Queensland. Additional samples and systematic work will be required to examine the evolutionary divergence of apparently isolated populations of the new species, and the significance of considerable genetic and morphological diversity within remaining populations of Pygopus lepidopodusfrom south-eastern and southern Australia. Copyright © 2010.

News Article | February 15, 2017
Site: www.eurekalert.org

Conservationists need to adopt a critical shift in thinking to keep the Earth's ecosystems diverse and useful in an increasingly "unnatural" world. That was among the conclusions of conservationists from every continent but Antarctica who gathered at the University of California, Berkeley in September 2015 to discuss the future of conservation. The meeting included a diverse mix of countries and of specialists, including ecologists, conservation biologists, paleobiologists, geologists, lawyers, policymakers and writers. Their discussions, summarized and published in Science on Feb. 9, recommend a more vigorous application of information garnered from the fossil record to forward-thinking conservation efforts. Their thinking goes like this: If conservationists reach back in history far enough, the past will suggest not only how ecosystems were once composed, but how they could best function in the future. Those at the meeting also said that conservationists must take a wider view of nature than they may have in the past. This still means, in many cases, saving individual species or attempting to maintain some ecosystems much as they are, which is how conservation is generally perceived. But it also means accepting that not all human uses of the environment are inherently bad. "Changed landscapes aren't necessarily trashed landscapes," said Anthony Barnosky, executive director of Stanford's Jasper Ridge Biological Preserve, professor emeritus of integrative biology at UC Berkeley and senior author of the Science paper. "These landscapes can actually be used to help in nature conservation. The question is, how do you best do that?" Also among the Science co-authors is Alexis Mychajliw, a Stanford biology researcher who does fieldwork in the Dominican Republic and whose work exemplifies the new recommended approach to conservation. She explores the fossil record of the island nation to see what its ecosystems were like both before European settlers and before any human habitation. The comparisons between these previous states and the present day can be striking. "Where I work, you only see two living terrestrial mammal species," said Mychajliw, a graduate student in the laboratory of Stanford biology professor Elizabeth Hadly, who is also a co-author of the paper. "But if you dig, actually dig in the dirt, you'll find there were once 25 species of mammals native to this area." This is just one instance of how the fossil record can fill in blanks in natural history that conservationists may be unaware are even missing. Rather than rely on reports or conjecture about what the natural world was like 500 years ago, specialists can piece together what it was like during various periods stretching back millions of years. Given that some natural cycles work on these grand timescales, going back even further than centuries helps explain how cycles may overlap and interact now and in the future. In turn, that can reveal apparent shifts in the natural world that are worthy of concern. Having access to what an ecosystem looked like at different periods in the past also suggests options for creating, achieving and maintaining conservation goals. Already, about 47 percent of ice-free land in the world has been transformed into what ecologists call "novel ecosystems." These ecosystems are unique assemblages of species or systems that didn't exist in pre-industrial times and include cropland, pastureland and timber plantations. The Science paper ("Merging Paleobiology with Conservation Biology to Guide the Future of Terrestrial Ecosystems") points out that these novel ecosystems are unlikely to be restored to what they were before humans. That may not be a bad thing. Instead, the authors suggest that there may be cases where conservationists should embrace novelty to understand how to move forward while supporting both natural diversity and civilization. An example is Stanford's Jasper Ridge Biological Preserve, says Hadly, who is the preserve's faculty director. "Here we have a landscape that humans have used heavily for centuries," she said. "The species that dominate have changed through time, some of them invasives, but it still preserves a remarkable slice of California biodiversity and offers a refuge of nature in the midst of Silicon Valley. Going into the future, we expect more change, but that doesn't lessen its conservation value." Whether an area is novel or historical, the paper argues that conservationists need to carefully consider the services provided by an ecosystem, including air and water purification, carbon sequestration, use of land for agriculture and tourism and the less tangible value of human interactions with the wild. "We rely on nature for almost everything: clean water, food, materials for construction and making computers and phones," said Allison Stegner, postdoctoral research associate at the University of Wisconsin-Madison, former graduate student at UC Berkeley and co-author of the paper. "The pace of global change today is so fast that we stand to lose all of those things that we rely on. Coming up with new approaches to conservation is essential to maintaining human life." The authors say keeping nature diverse, healthy and useful will likely require both historical and novel habitats, efforts that focus on saving species and efforts that don't, input from people who use nature for different purposes and data from very long timescales, some of which can only be obtained through the fossil record. They also said that identifying stakes and stakeholders is a task that goes beyond the sciences. With that in mind, the workshop that led to the paper opened with words from non-scientists, including a senior policy adviser to California Gov. Jerry Brown and a fiction writer who is also the mother of one of the researchers. "They fostered a more humanist approach to our collaboration that lingers," said Hadly. Co-authors of this paper include Patrick Gonzalez, Jason Head, P. David Polly, A. Michelle Lawing, Jussi T. Eronen, David D. Ackerly, Ken Alex, Eric Biber, Jessica Blois, Justin Brashares, Gerardo Ceballos, Edward Davis, Gregory P. Dietl, Rodolfo Dirzo, Holly Doremus, Mikael Fortelius, Harry Greene, Jessica Hellmann, Thomas Hickler, Stephen T. Jackson, Melissa Kemp, Paul L. Koch, Claire Kremen, Emily L. Lindsey, Cindy Looy, Charles R. Marshall, Chase Mendenhall, Andreas Mulch, Carsten Nowak, Uma Ramakrishnan, Jan Schnitzler, Kashish Das Shrestha, Katherine Solari, Lynn Stegner, Nils Chr. Stenseth, Marvalee H. Wake, and Zhibin Zhang. During this research, Barnosky was in the Department of Integrative Biology and Museums of Paleontology and Vertebrate Zoology, University of California, Berkeley. Hadly is also the Paul S. and Billie Achilles Professor in Environmental Biology, senior fellow at the Stanford Woods Institute for the Environment, faculty director of Jasper Ridge Biological Preserve and a member of Stanford Bio-X. Stegner received her B.S. in Ecology and Evolutionary Biology from Stanford in 2010. This workshop was funded by the Integrative Climate Change Biology Group, International Union of Biological Sciences; the Museum of Paleontology, Berkeley Initiative for Global Change Biology, and Office of the Vice Chancellor for Research at the University of California, Berkeley; the Conservation Paleobiology Group at the Department of Biology, Stanford University; and the Senckenberg Biodiversity and Climate Research Centre, Frankfurt, Germany. Additional funding for this work came from the National Science Foundation.

Campbell K.E.,Vertebrate Zoology | Prothero D.R.,Occidental College | Romero-Pittman L.,Instituto Geologico | Hertel F.,Northridge | Rivera N.,Occidental College
Journal of South American Earth Sciences | Year: 2010

The chronostratigraphy of the youngest Neogene deposits of the Amazon Basin, which comprise the Madre de Dios Formation in eastern Peru, remains unresolved. Although 40Ar/39Ar dates on two volcanic ashes from this formation in Peru provide critical baseline data points, stratigraphic correlations among scattered riverine outcrops in adjacent drainage basins remain problematic. To refine the chronostratigraphy of the Madre de Dios Formation, we report here the magnetostratigraphy of an outcrop on the Madre de Dios River in southeastern Peru. A total of 18 polarity zones was obtained in the ∼65-m-thick Cerro Colorado section, which we correlate to magnetozones Chrons C4Ar to C2An (9.5-3.0Ma) based on the prior 40Ar/39Ar dates. These results confirm the late Miocene age of a gomphothere recovered from the Ipururo Formation, which underlies the late Miocene Ucayali Unconformity at the base of the Cerro Colorado outcrop. The results also support earlier interpretations of a late Miocene age for other fossils of North American mammals recovered from basal conglomeratic deposits of the Madre de Dios Formation immediately above the Ucayali Unconformity. These mammals include other gomphotheres, peccaries, and tapirs, and their presence in South America in the late Miocene is recognized as part of the first pulse of the Great American Faunal Interchange. © 2009 Elsevier Ltd.

PubMed | CONICET, Museo Argentino de Ciencias Naturales Bernardino Rivadavia and Vertebrate Zoology
Type: Journal Article | Journal: Nature | Year: 2015

The platyrrhine primates, or New World monkeys, are immigrant mammals whose fossil record comes from Tertiary and Quaternary sediments of South America and the Caribbean Greater Antilles. The time and place of platyrrhine origins are some of the most controversial issues in primate palaeontology, although an African Palaeogene ancestry has been presumed by most primatologists. Until now, the oldest fossil records of New World monkeys have come from Salla, Bolivia, and date to approximately 26million years ago, or the Late Oligocene epoch. Here we report the discovery of new primates from the ?Late Eocene epoch of Amazonian Peru, which extends the fossil record of primates in South America back approximately 10million years. The new specimens are important for understanding the origin and early evolution of modern platyrrhine primates because they bear little resemblance to any extinct or living South American primate, but they do bear striking resemblances to Eocene African anthropoids, and our phylogenetic analysis suggests a relationship with African taxa. The discovery of these new primates brings the first appearance datum of caviomorph rodents and primates in South America back into close correspondence, but raises new questions about the timing and means of arrival of these two mammalian groups.

Frailey C.D.,Johnson County Community College | Frailey C.D.,University of Kansas | Campbell Jr. K.E.,Vertebrate Zoology
Journal of Paleontology | Year: 2012

Two new, extinct taxa of peccaries from upper Miocene deposits of the western Amazon Basin provide the first data documenting the presence of these North American mammals in South America in the Miocene. One, Sylvochoerus woodburnei n. gen. n. sp., is allied morphologically to Tayassu pecari, whereas the second, Waldochoerus bassleri n. gen. n. sp., is more similar to Pecari tajacu. Both new taxa reflect an intermediate position between middle Miocene peccaries and modern Tayassu and Pecari. The specimens reported here were unstudied, but when collected they were referred to living species of Tayassu and Pecari based on their general similarity to species of those two living genera, and they were dated to the Pleistocene, presumably based on a longstanding model of the Great American Faunal Interchange. The presence of peccaries in South America at approximately the same time that South American ground sloths began appearing in upper Miocene deposits of North America, and soon after the appearance of gomphotheres in South America, indicates that dispersal between the Americas was earlier and involved more taxa than previously interpreted. Molecular divergence data are consistent, in part, with a late Miocene dispersal of peccaries to South America. Copyright © 2012, The Paleontological Society.

Prothero D.R.,Vertebrate Paleontology | Campbell Jr. K.E.,Vertebrate Zoology | Beatty B.L.,New York Institute of Technology | Beatty B.L.,Smithsonian Institution | Frailey C.D.,Johnson County Community College
Journal of Paleontology | Year: 2014

A new dromomerycine palaeomerycid artiodactyl, Surameryx acrensis new genus new species, from upper Miocene deposits of the Amazon Basin documents the first and only known occurrence of this Northern Hemisphere group in South America. Osteological characters place the new taxon among the earliest known dromomerycine artiodactyls, most similar to Barbouromeryx trigonocorneus, which lived in North America during the early to middle Miocene, 20-16 Ma. Although it has long been assumed that the Great American Biotic Interchange (GABI) began with the closure of the Isthmus of Panama in the late Pliocene, or ca. 3.0-2.5 Ma, the presence of this North American immigrant in Amazonia is further evidence that terrestrial connections between North America and South America through Panama existed as early as the early late Miocene, or ca. 9.5 Ma. This early interchange date was previously indicated by approximately coeval specimens of proboscideans, peccaries, and tapirs in South America and ground sloths in North America. Although palaeomerycids apparently never flourished in South America, proboscideans thrived there until the end of the Pleistocene, and peccaries and tapirs diversified and still live there today. © 2014, The Paleontological Society.

Ciancio M.R.,National University of La Plata | Carlini A.A.,National University of La Plata | Campbell K.E.,Vertebrate Zoology | Scillato-Yane G.J.,National University of La Plata
Journal of Systematic Palaeontology | Year: 2013

The record of Palaeogene cingulate xenarthrans in low latitudes is very poor. The cingulate fauna from the Yurúa River near Santa Rosa in eastern Perú is important because it is one of the oldest known from the Palaeogene of Perú and because of its tropical latitudinal position. Although remains are scarce, we recognize three new taxa: two species of Astegotheriini (Dasypodidae); Parastegosimpsonia peruana gen. et sp. nov., of small size, related to Eocene species from Patagonia; and another new species, ?Parastegosimpsonia sp. nov., which consists of an incomplete osteoderm representing the largest species of this tribe. A third species, Yuruatherium tropicalis gen. et sp. nov., of indeterminate suprageneric rank, shares features with Machlydotherium Ameghino (Casamayoran-Tinguirirican SALMA - middle Eocene-early Oligocene of Patagonia) and is similar to Eocoleophorus Oliveira et al. (Deseadan SALMA - late Oligocene of Brazil). We assign ?Machlydotherium intortum Ameghino (from the late Eocene of Patagonia) to Yuruatherium. Sediments bearing these cingulates also yielded rodents, marsupials and notoungulates, among the most frequent mammals. The absolute age of the sediments is unknown but an estimated age is inferred from studies of the mammalian assemblages. The age of the Santa Rosa local fauna is still controversial and given the groups taken into account, could be from Early Eocene to Late Oligocene. According to sequences of southern cingulate faunas (especially those of Dasypodidae), the cingulates from Santa Rosa also suggest an age between the Late Eocene and Early Oligocene. Nevertheless, the very low latitude of the Santa Rosa local fauna should be taken into account because in lower latitudes it is not uncommon to find taxa with a more generalized set of characters than those present in contemporary taxa from higher latitudes. © 2013 Copyright Taylor and Francis Group, LLC.

Campbell Jr. K.E.,Vertebrate Zoology | Bochenski Z.M.,Polish Academy of Sciences
Acta Palaeontologica Polonica | Year: 2013

Two new species of miniature owls are described from the upper Pleistocene asphalt deposits of Rancho La Brea, California. The first is assigned to the extant genus Glaucidium, as Glaucidium kurochkini sp. nov., and the second is placed in a new genus Asphaltoglaux, as Asphaltoglaux cecileae sp. nov. Both new species are based on tarsometatarsi, and each is represented by various elements. These are the second and third extinct owls to be described among the nine strigiform species from Rancho La Brea. The new species of Glaucidium is also recognized from the upper Pleistocene asphalt deposits of Carpinteria, California, which lends support to the hypothesis that southwestern coastal California was comparable to an island in the late Pleistocene. Recognition of these two new strigiform taxa brings to 22 the number of known extinct avian species from Rancho La Brea. Copyright © 2013 K.E. Campbell, Jr. and Z.M. Bochenski. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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