DOCSLIB.ORG

A 17-My-Old Whale Constrains Onset of Uplift and Climate Change in East Africa

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
A 17-My-Old Whale Constrains Onset of Uplift and Climate Change in East Africa A 17-My-old whale constrains onset of uplift and climate change in east Africa Henry Wichuraa,1, Louis L. Jacobsb, Andrew Linb, Michael J. Polcynb, Fredrick K. Manthic, Dale A. Winklerb, Manfred R. Streckera, and Matthew Clemensb aInstitute of Earth and Environmental Sciences, University of Potsdam, 14476 Potsdam, Germany; bRoy M. Huffington Department of Earth Sciences, Southern Methodist University, Dallas, TX 75275; and cDepartment of Earth Sciences, National Museums of Kenya, 00100 Nairobi, Kenya Edited by Thure E. Cerling, University of Utah, Salt Lake City, UT, and approved February 24, 2015 (received for review November 10, 2014) Timing and magnitude of surface uplift are key to understanding with modern Indopacetus, Hyperoodon,andMesoplodon plus the impact of crustal deformation and topographic growth on four extinct genera. atmospheric circulation, environmental conditions, and surface Beaked whales are predicted by molecular clocks to have processes. Uplift of the East African Plateau is linked to mantle originated 26.52–35.82 Ma (6). The early record of fossil ziphiids processes, but paleoaltimetry data are too scarce to constrain is poor, but at 17.1 ± 1.0 Ma, the Kenyan specimen is currently plateau evolution and subsequent vertical motions associated the most precisely dated ziphiid fossil. Phylogenetic analysis nests with rifting. Here, we assess the paleotopographic implications the Turkana ziphiid with three modern genera, most notably Meso- of a beaked whale fossil (Ziphiidae) from the Turkana region of plodon, which has species that are estimated to have diverged at Kenya found 740 km inland from the present-day coastline of the 16.6 Ma (6, 7). Thus, the geochronologic constraint provided Indian Ocean at an elevation of 620 m. The specimen is ∼17 My old by the Turkana ziphiid is consistent with molecular predictions. and represents the oldest derived beaked whale known, consis- tent with molecular estimates of the emergence of modern strap- Ziphiids and Other Cetaceans in Present-Day and Paleorivers toothed whales (Mesoplodon). The whale traveled from the Indian Modern ziphiids are open-ocean, deep-diving specialized suction Ocean inland along an eastward-directed drainage system con- feeders that prey mainly on squid (8). Phylogenetic analyses in- trolled by the Cretaceous Anza Graben and was stranded slightly corporating molecular data (9) indicate that they are nested above sea level. Surface uplift from near sea level coincides with between the freshwater Ganges River dolphin (Platanista) and paleoclimatic change from a humid environment to highly variable the Yangtze (Lipotes) plus South American river dolphins (Inia and much drier conditions, which altered biotic communities and and Pontoporia). The Kenyan whale possesses derived ziphiid drove evolution in east Africa, including that of primates. characters of the beak, including hyperostosis, reduced gape, and evolutionary loss of teeth (characters not found in any clade of east Africa | Ziphiidae | uplift | drainage | paleoenvironment river dolphins). Moreover, the Turkana ziphiid’stotalbody length falls within the range of modern ziphiids (10) and is up to he Turkana ziphiid was found at Loperot in West Turkana, three times that observed in river dolphins. TKenya and described in 1975 by James G. Mead (1), who A wide variety of present-day marine whales has been ob- listed associated fauna, including mollusks, fish, crocodiles, tur- served in rivers, some of which may be associated with seasonal tles, and mammals, notably primates. Mead (1) detailed the migrations (11, 12). Modern ziphiids occasionally enter rivers, anatomy of the whale fossil, estimated its length in life at some 7 such as occurred in the 2006 stranding of Hyperoodon ampullatus m, and speculated that it was an open-ocean whale that became in the Thames River at London. Killer whales (Orcinus orca)have stranded after swimming up an eastward-flowing river and was then preserved near where it died. After the original publication Significance of this fossil find (1), the specimen went missing until late 2011, when it was rediscovered at Harvard University and returned to An enigmatic fossil representing the deep-diving, open-ocean the National Museums of Kenya (KNM), where it is curated whale family Ziphiidae found 740 km inland and at 620 m el- under the number KNM-LP 52956. evation in West Turkana, Kenya was rediscovered after it went Because the whale was found during the pre-Global Posi- missing for more than 30 years. This stranded whale fossil tioning System era, we studied the original 1964 Harvard expe- provides the first constraint on the initiation of east African dition field notes and catalog to locate the exact site of the ziphiid uplift from near sea level at 17 Ma, limiting the timing and (2°23′30″ N, 35°52′30″ Ebytriangulation)(Fig.1C)incoarse initial elevation of environmental change indicated by geo- fluvial sandstones and conglomerates of the Lower to Middle dynamic and climatic modeling, paleosols, isotopes, paleobot- Miocene Auwerwer Formation (2–4) ∼7 m below a basalt dated any, and the mammalian fossil record. At 17 Ma, elevation was at 17.1 ± 1.0 Ma (4). Although located in an area repeatedly low, rainfall was high, vegetation was forested, and mammalian affected by extensional processes since the Cretaceous, the fossil communities contained immigrants and native African species, location corresponds to the northern periphery of the Late Ce- including diverse primates. Uplift resulted in increasing aridity nozoic East African Plateau (EAP) (Fig. 1B). The specimen and open habitats that drove human evolution. consists of the rostrum and the ascending processes of the maxillae and premaxillae (length of 82 cm and width of 55 cm) Author contributions: H.W. and L.L.J. designed research; H.W., L.L.J., A.L., M.J.P., F.K.M., D.A.W., M.R.S., and M.C. performed research; H.W., L.L.J., A.L., M.J.P., F.K.M., D.A.W., broken from the rest of the skull (1). Five phylogenetically in- M.R.S., and M.C. analyzed data; and H.W., L.L.J., and M.R.S. wrote the paper. formative characters of KNM-LP 52956 (Fig. 2A and SI Ap- The authors declare no conflict of interest. pendix) were scored and entered into a data matrix of 46 This article is a PNAS Direct Submission. characters and 29 fossil and recent taxa (5). A traditional Wagner Data deposition: The 3D digital model of KNM-LP 52956 reported in this paper has been tree search (one random seed and 10 replications) applied to archived at www.digimorph.org/specimens/Turkana_ziphiid. unweighted and unordered characters yielded 17 most parsimo- 1To whom correspondence should be addressed. Email: [email protected]. nious trees of 124 steps (Fig. 2B). In all most parsimonious trees, This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10. the Turkana ziphiid falls in a derived but unresolved clade 1073/pnas.1421502112/-/DCSupplemental. 3910–3915 | PNAS | March 31, 2015 | vol. 112 | no. 13 www.pnas.org/cgi/doi/10.1073/pnas.1421502112 Downloaded by guest on September 23, 2021 A B Ethiopian N 150 km zz zzzzzzz zzzz Plateau zzzzzz 4° Kenya whale 17.1 Ma (K/Ar) ANZA GRABEN C rst KENYA 0° Kenya whale Lokichar Fault RIFT Lokone HoHorst Lake Victoria LAMU Loperot Yatta lava flow EMBAYMENT 13.51 Ma (K/Ar) Auwerwer Hills N Elevation (m) East African 4° 5 km 3000 Plateau Auwerwer Basalts - Middle Miocene 2000 Indian Ocean Auwerwer Formation - Early to Middle Miocene 1000 33° 40° Lokone Formation - Oligocene to 500 Early Miocene Miocene – Recent rifting Normal faults Paleoaltimetric data Basement - Precambrian 0 Jurassic – Cretaceous rifting zzzz Shear zone Fig. 1. (A) Topography of Africa and bathymetry of the Atlantic and Indian Oceans. The white box indicates the location of the principal map shown in B. (B) Geological setting of the Cenozoic East African Rift System and topography of the present EAP based on a digital elevation model derived from Satellite Radar Topography Mission data. Elevations >1,000 m are enclosed by a white line. Rock ages for the basalt overlaying the beaked whale fossil and the Yatta lava flow phonolites are based on the radioactive decay of potassium (40K) into argon (40Ar). The white box indicates the location of the geological map in C. (C) Geological map of the Oligo-Miocene Lokichar Basin. The red diamond indicates the beaked whale fossil locality (Williams’ Flat) within the Lower to Middle Miocene Auwerwer Formation. been reported 161 km up the Columbia River at an elevation of fluviolacustrine strata that transition upward into marine units 6 m and river depth >10 m (Table 1) (13). In 2007, mother and toward the Kenya–Somalia coast in the Lamu Embayment (Fig. calf humpback whales (Megaptera novaeangliae) swam 133 km 1B) (19, 20). The Anza Graben constitutes a failed rift arm, upstream to Sacramento, CA (elevation of 4 m and river depth of which once linked rifting in the Central African Shear Zone with ∼10 m) (Table 1) (13). An Antarctic minke whale (Balaenoptera extensional processes in eastern Kenya that led to the separation bonaerensis) swam 1,000 km up the Amazon and its tributary the of Madagascar from Africa (19). Tapajós, traveling as much as 83 km in 1 day (Table 1) (14). In The size of the ziphiid, the regional context of the fluvial sedi- comparison, South American Sotalia fluvatilis, a river dolphin, has ments in which it was found, and the fauna associated with it in- a normal range that reaches an elevation of ∼100 m, where river dicate that the path to its stranding site was a sizable low-gradient depths are 10–30 m, 3,600 km up the Amazon drainage from the river. The ziphiid may have mistakenly entered the river while Atlantic Ocean (Table 1) (15).
Load more

Recommended publications
  • Abstractbook 6Ewvp.Pdf
    6th European Workshop on Vertebrate Palaeontology - Florence and Montevarchi (Italy) - September 19-22, 2001 The organizing team welcomes the participants in the 6th European Workshop of Vertebrate Paleontology in Florence and expresses its deepest thanks to the many colleagues that enthusiastically answered to our call making this issue possible. The organizers hope the participants will find Florence not only that jewel-case of art celebrated all over the world, but also an appropriate place for discussing crumbled fossil bones. May the meeting come up to everybody’s best expectations! The 6th European Workshop on Vertebrate Paleontology has been made possible, thanks to the support and collaboration obtained from the Tethys Cultural Association, the Section of Geology and Paleontology of the Museum of Natural History of Florence, the Department of Earth Sciences of Florence and the Museum of Plaeontology of the Accademia Valdarnese del Poggio of Montevarchi. The organizers would like to thank the administration of the Section of Geology and Paleontology of the Museum of Natural History of Florence and the Accademia Valdarnese del Poggio for granting their facilities, and all the volunteers for their generous donation of time and talent. Without their dedication and tireless efforts, this issue would have been impossible. Special thanks are due to Maria Cristina Andreani, manager of the display department of the Section of Geology and Paleontology of the Museum of Natural History of Florence, for her assistance and for creating the logo and producing the panels of explanation of the evolution of the Upper Valdarno. The organizers are also grateful to the Comune of Montevarchi for offering the conference lunch and to Tiziana Vitali for arranging the tea party.
    [Show full text]
  • Arktocara Yakataga, a New Fossil Odontocete (Mammalia, Cetacea) from the Oligocene of Alaska and the Antiquity of Platanistoidea
    Arktocara yakataga, a new fossil odontocete (Mammalia, Cetacea) from the Oligocene of Alaska and the antiquity of Platanistoidea Alexandra T. Boersma1,2 and Nicholas D. Pyenson1,3 1 Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, D.C., United States of America 2 College of Extended Education, California State University, Monterey Bay, Seaside, CA, United States of America 3 Departments of Mammology and Paleontology, Burke Museum of Natural History and Culture, Seattle, WA, United States of America ABSTRACT The diversification of crown cetacean lineages (i.e., crown Odontoceti and crown Mysticeti) occurred throughout the Oligocene, but it remains an ongoing challenge to resolve the phylogenetic pattern of their origins, especially with respect to stem lineages. One extant monotypic lineage, Platanista gangetica (the Ganges and Indus river dolphin), is the sole surviving member of the broader group Platanistoidea, with many fossil relatives that range from Oligocene to Miocene in age. Curiously, the highly threatened Platanista is restricted today to freshwater river systems of South Asia, yet nearly all fossil platanistoids are known globally from marine rocks, suggesting a marine ancestry for this group. In recent years, studies on the phylogenetic relationships in Platanistoidea have reached a general consensus about the membership of different sub-clades and putative extinct groups, although the position of some platanistoid groups (e.g., Waipatiidae) has been contested. Here we describe a new genus and species of fossil platanistoid, Arktocara yakataga, gen. et sp. nov. from the Oligocene of Alaska, USA. The type and only known specimen was collected from the marine Poul Submitted 16 May 2016 Creek Formation, a unit known to include Oligocene strata, exposed in the Yakutat Accepted 13 July 2016 City and Borough of Southeast Alaska.
    [Show full text]
  • The Shark-Toothed Dolphin Squalodon Cetacea
    Carnets Geol. 20 (2) E-ISSN 1634-0744 DOI 10.4267/2042/70716 The shark-toothed dolphin Squalodon (Cetacea: Odontoceti) from the remarkable Montagna della Majella marine vertebrate assemblage (Bolognano Formation, central Italy) Alberto COLLARETA 1 Andrea DI CENCIO 2 Renato RICCI 3 Giovanni BIANUCCI 4 Abstract: The extinct family Squalodontidae consists of heterodont, medium-sized odontocetes, featu- ring a long rostrum that houses large, procumbent incisors and heavily ornamented postcanine teeth carrying accessory denticles, hence their vernacular name, "shark-toothed dolphins". These longirostri- ne toothed whales are often seen as bridging the anatomical gap between archaic Oligocene odontoce- tes and their late Miocene to Holocene relatives. Possibly among the major marine predators of their ti- me, the shark-toothed dolphins are important components of several lower Miocene marine-mammal assemblages from the North Atlantic and Mediterranean/Paratethysian realms. In the present work, a partial skull of Squalodontidae is described from the strata of the Bolognano Formation cropping out in the northeastern sector of the Montagna della Majella massif (Abruzzo, central Italy), which has pre- viously yielded a rich lower Miocene marine-vertebrate assemblage, including eleven taxa of elasmo- branchs as well as subordinate teleosts and very fragmentary remains of marine reptiles and mam- mals. The specimen consists of the anterodorsal portion of a rostrum, preserving parts of both pre- maxillae and left maxilla, and the anteriormost seven upper left teeth. This partial skull is here identi- fied as belonging to the genus Squalodon, whose presence in the Montagna della Majella vertebrate assemblage had already been tentatively proposed on the basis of two fragmentary teeth.
    [Show full text]
  • 1 Published in Journal of South American Earth Sciences, 31:414
    Published in Journal of South American Earth Sciences, 31:414-425, 2011 (This is a prepublication version, with larger illustrations) A high resolution stratigraphic framework for the remarkable fossil cetacean assemblage of the Miocene/Pliocene Pisco Formation, Peru Leonard Brand a,*, Mario Urbina b, Arthur Chadwick c, Thomas J. DeVries d, Raul Esperante e, a Department of Earth and Biological Sciences, Loma Linda University, Loma Linda, CA 92350 b Museo de Historia Natural, Lima 14, Peru c Southwestern Adventist University, Keene, TX 76059 d Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98195 e Geoscience Research Institute, Loma Linda, CA 92350 Abstract The Miocene/Pliocene Pisco Formation of Peru contains a rich marine vertebrate fossil record, providing a unique opportunity for the study of paleoecology and evolution, along with the sedimentological context of the fossils. The lack of a high-resolution stratigraphic framework has hampered such study. In this paper we develop the needed stratigraphy for the areas in the Pisco Formation where most of the vertebrate paleontological research is occurring. In the Ica Valley and in the vicinity of Lomas, series of lithologically or paleontologically unique marker beds were identified. These were walked out and documented with GPS technology. Measured sections connecting these marker beds provide a stratigraphic framework for the areas studied. GPS locations, maps of the marker beds on aerial photographs, and outcrop photographs allow field determination of the stratigraphic positions of study areas. Keywords: Stratigraphy, Miocene, Pliocene, Pisco, Peru * Corresponding author. FAX 909-558-0259 E-mail address: [email protected] (Leonard Brand) 1.
    [Show full text]
  • The Gonads of the South American Dolphins, Inia Geoffrensis, Pontoporia Blainvillei, and Sotalia Fluviatilis
    University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Publications, Agencies and Staff of the U.S. Department of Commerce U.S. Department of Commerce 5-1971 The Gonads of the South American Dolphins, Inia geoffrensis, Pontoporia blainvillei, and Sotalia fluviatilis Richard J. Harrison Robert L. Brownell Jr. US Fish and Wildlife Service, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/usdeptcommercepub Part of the Environmental Sciences Commons Harrison, Richard J. and Brownell, Robert L. Jr., "The Gonads of the South American Dolphins, Inia geoffrensis, Pontoporia blainvillei, and Sotalia fluviatilis" (1971). Publications, Agencies and Staff of the U.S. Department of Commerce. 92. https://digitalcommons.unl.edu/usdeptcommercepub/92 This Article is brought to you for free and open access by the U.S. Department of Commerce at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Publications, Agencies and Staff of the U.S. Department of Commerce by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. Journal of Mammalogy, Vol. 52, No. 2 (May, 1971), pp. 413-419 THE GONADS OF THE SOUTH AMERICAN DOLPHINS, INIA GEOFFRENSIS, PONTOPORIA BLAINVILLEI, AND SOTALIA FLUVIATILIS RICHARD J. HARRISON AND ROBERT L. BROWNELL, JR. ABSTRACT.-Theappearances of the gonads are described in males and females of 18 Inia geoffrensis, 11 Pontoporia blainvillei, and eight Sotalia fluviatilis from South America. Males of I. geoffrensis become sexually active at a length of about 228 centimeters, females at 175 to 180 centimeters. Length at birth is 76 to 80 centimeters; parturition occurs from about July to September in the upper Amazon.
    [Show full text]
  • Download Full Article in PDF Format
    A new marine vertebrate assemblage from the Late Neogene Purisima Formation in Central California, part II: Pinnipeds and Cetaceans Robert W. BOESSENECKER Department of Geology, University of Otago, 360 Leith Walk, P.O. Box 56, Dunedin, 9054 (New Zealand) and Department of Earth Sciences, Montana State University 200 Traphagen Hall, Bozeman, MT, 59715 (USA) and University of California Museum of Paleontology 1101 Valley Life Sciences Building, Berkeley, CA, 94720 (USA) [email protected] Boessenecker R. W. 2013. — A new marine vertebrate assemblage from the Late Neogene Purisima Formation in Central California, part II: Pinnipeds and Cetaceans. Geodiversitas 35 (4): 815-940. http://dx.doi.org/g2013n4a5 ABSTRACT e newly discovered Upper Miocene to Upper Pliocene San Gregorio assem- blage of the Purisima Formation in Central California has yielded a diverse collection of 34 marine vertebrate taxa, including eight sharks, two bony fish, three marine birds (described in a previous study), and 21 marine mammals. Pinnipeds include the walrus Dusignathus sp., cf. D. seftoni, the fur seal Cal- lorhinus sp., cf. C. gilmorei, and indeterminate otariid bones. Baleen whales include dwarf mysticetes (Herpetocetus bramblei Whitmore & Barnes, 2008, Herpetocetus sp.), two right whales (cf. Eubalaena sp. 1, cf. Eubalaena sp. 2), at least three balaenopterids (“Balaenoptera” cortesi “var.” portisi Sacco, 1890, cf. Balaenoptera, Balaenopteridae gen. et sp. indet.) and a new species of rorqual (Balaenoptera bertae n. sp.) that exhibits a number of derived features that place it within the genus Balaenoptera. is new species of Balaenoptera is relatively small (estimated 61 cm bizygomatic width) and exhibits a comparatively nar- row vertex, an obliquely (but precipitously) sloping frontal adjacent to vertex, anteriorly directed and short zygomatic processes, and squamosal creases.
    [Show full text]
  • List of Marine Mammal Species and Subspecies
    List of Marine Mammal Species and Subspecies Introduction The Committee on Taxonomy, chaired by Patricia Rosel, produced the first official Society for Marine Mammalogy list of marine mammal species and subspecies in 2010. Consensus on some issues has not been possible; this is reflected in the footnotes. The list is updated at least annually. The current version was updated in May 2020. This list can be cited as follows: “Committee on Taxonomy. 2019. List of marine mammal species and subspecies. Society for Marine Mammalogy, www.marinemammalscience.org, consulted on [date].” This list includes living and recently extinct (within historical times) species and subspecies. It is meant to reflect prevailing usage and recent revisions published in the peer-reviewed literature. Classification and scientific names follow Rice (1998), with adjustments reflecting more recent literature. Author(s) and year of description of each taxon follow the Latin (scientific) species name; when these are enclosed in parentheses, the taxon was originally described in a different genus. The Committee annually considers and evaluates new, peer-reviewed literature that proposes taxonomic changes. The Committee’s focus is on alpha taxonomy (describing and naming taxa) and beta taxonomy primarily at lower levels of the hierarchy (subspecies, species and genera), although it may evaluate issues at higher levels if deemed necessary. Proposals for new, taxonomically distinct taxa require a formal, peer-reviewed study and should provide robust evidence that some subspecies or species criterion was met. For review of species concepts, see Reeves et al. (2004), Orr and Coyne (2004), de Queiroz (2007), Perrin (2009) and Taylor et al.
    [Show full text]
  • Cetacea: Phocoenidae) from the Upper Part of the Horokaoshirarika Formation (Lower Pliocene), Numata Town, Hokkaido, Japan, and Its Phylogenetic Position
    Palaeontologia Electronica palaeo-electronica.org A new skull of the fossil porpoise Numataphocoena yamashitai (Cetacea: Phocoenidae) from the upper part of the Horokaoshirarika Formation (lower Pliocene), Numata Town, Hokkaido, Japan, and its phylogenetic position Yoshihiro Tanaka and Hiroto Ichishima ABSTRACT An early Pliocene porpoise, Numataphocoena yamashitai from Hokkaido, Japan, is known from the holotype, a fairly well-preserved skeleton with an incomplete skull and a referred earbone. A new skull referred to Numataphocoena yamashitai found from almost the same locality as the holotype is interesting because it expands knowl- edge of skull morphology and improves the diagnosis of this taxon. Numataphocoena yamashitai differs from other phocoenids in having the characteristic feature in the maxilla associated with the posterior dorsal infraorbital foramen, narrower and sharper anterior part of the internal acoustic meatus, and a robust anterior process of the peri- otic. A new cladistic analysis places Numataphocoena yamashitai adjacent to Haboro- phocoena toyoshimai and Haborophocoena minutus, among a clade of early branching phocoenids, all of which are chronologically and geographically close to each other. The new skull is probably a younger individual because it is about 80% the size of that of the holotype and it shows closed but unfused sutures. Our description of this specimen helps to understand the intraspecies variation of the extinct species Numataphocoena yamashitai. Yoshihiro Tanaka. Numata Fossil Museum, 2-7-49, Minami 1, Numata Town, Hokkaido, 078-2225 Japan, [email protected] and Hokkaido University Museum, Kita 10, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810 Japan Hiroto Ichishima. Fukui Prefectural Dinosaur Museum, Terao 51-11, Muroko, Katsuyama, Fukui 911-8601, Japan, [email protected] Key words: skull; Phocoenidae; phylogeny; maxillary terrace; ontogeny; intraspecies variation Submission: 22 March 2016 Acceptance: 20 October 2016 Tanaka, Yoshihiro and Ichishima, Hiroto.
    [Show full text]
  • Food Consumption and Body Measurements of Amazon River Dolphins (Inia Geoffrensis)
    Aquatic Mammals 1999, 25.3, 173–182 Food consumption and body measurements of Amazon river dolphins (Inia geoffrensis) R. A. Kastelein1, B. Neurohr2, S. H. Nieuwstraten1 and P. R. Wiepkema3 1Harderwijk Marine Mammal Park, Strandboulevard Oost 1, 3841 AB Harderwijk, The Netherlands 2Tiergarten Nu¨rnberg, Am Tiergarten 30, D90480 Nu¨rnberg, Germany 3Emeritus Professor of Ethology, Wageningen Agricultural University, Stationsweg 1, 6861 EA Oosterbeek, The Netherlands Abstract dolphin is the most widespread freshwater dolphin in the world, its distribution is limited compared to This report is on the food consumption of 3 male that of most marine odontocetes and it is therefore Amazon river dolphins which were housed in water very likely to become a threatened species. For the of between 27 and 29 C at Duisburg Zoo, management of Amazon river dolphins in the wild, Germany. The food consumption of 2 animals was information is needed about the population size, recorded for 17 successive complete calendar years, age composition and sex ratio, seasonal distribu- that of the third animal for 3 complete successive tion, diet, energy requirements relative to seasonal years. In male 002 the total annual food intake prey distribution and density, and about competi- increased to 1280 kg at the age of 10 years, after tion with other animals and with fisheries. This which it decreased slightly and stabilised at around information could facilitate prey management 1170 kg/year. Male 001 was adult on arrival at the to allow for a certain number of Amazon river zoo. His annual food intake fluctuated at around dolphins in their distribution area.
    [Show full text]
  • From Peru Sheds Light on the Early Miocene Platanistoid Disparity And
    A new large squalodelphinid (Cetacea, Odontoceti) from Peru sheds light on the Early Miocene platanistoid disparity and ecology Giovanni Bianucci, Giulia Bosio, Elisa Malinverno, Christian de Muizon, Igor Villa, Mario Urbina, Olivier Lambert To cite this version: Giovanni Bianucci, Giulia Bosio, Elisa Malinverno, Christian de Muizon, Igor Villa, et al.. A new large squalodelphinid (Cetacea, Odontoceti) from Peru sheds light on the Early Miocene platanis- toid disparity and ecology. Royal Society Open Science, The Royal Society, 2018, 5 (4), pp.172302. 10.1098/rsos.172302. hal-02611968 HAL Id: hal-02611968 https://hal.archives-ouvertes.fr/hal-02611968 Submitted on 18 May 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Downloaded from http://rsos.royalsocietypublishing.org/ on April 18, 2018 A new large squalodelphinid (Cetacea, rsos.royalsocietypublishing.org Odontoceti) from Peru Research sheds light on the Early Cite this article: Bianucci G, Bosio G, Miocene platanistoid Malinverno E, de Muizon C, Villa IM, Urbina M, Lambert O. 2018 A new large squalodelphinid (Cetacea, Odontoceti) from Peru sheds light on disparity and ecology the Early Miocene platanistoid disparity and 1 2 2 ecology. R. Soc.
    [Show full text]
  • Anatomical Description and Phylogenetic Analysis of Miocene
    Southern Methodist University SMU Scholar Collection of Engaged Learning Engaged Learning 4-15-2013 Anatomical description and phylogenetic analysis of Miocene beaked whale from the East African Rift Valley, Kenya Andrew Lin Southern Methodist University, [email protected] Follow this and additional works at: https://scholar.smu.edu/upjournal_research Part of the Earth Sciences Commons Recommended Citation Lin, Andrew, "Anatomical description and phylogenetic analysis of Miocene beaked whale from the East African Rift alV ley, Kenya" (2013). Collection of Engaged Learning. 10. https://scholar.smu.edu/upjournal_research/10 This document is brought to you for free and open access by the Engaged Learning at SMU Scholar. It has been accepted for inclusion in Collection of Engaged Learning by an authorized administrator of SMU Scholar. For more information, please visit http://digitalrepository.smu.edu. 1 Anatomical description and phylogenetic analysis of Miocene beaked whale from the East African Rift Valley, Kenya by Andrew Lin Undergraduate Senior Thesis Huffington Department of Earth Sciences Southern Methodist University Dallas, TX 75275 Abstract This study compares the anatomy of a Miocene whale fossil found in Kenya to that of modern and other fossil beaked whales in order to identify it using phylogenetic analysis. The specimen is a partial skull and lacks diagnostic features present in the posterior regions of the skull, but a parsimony analysis based on available characters determined the whale is likely linked to modern Mesoplodon and Hyperoodon. Identification of this specimen is necessary for biogeographical purposes and other investigations using the fossil as a marker for the paleocoastline. Furthermore, this whale is an important and unique tool that can be used to study the development of the East African Rift.
    [Show full text]
  • Subsurface and Nighttime Behaviour of Pantropical Spotted Dolphins in Hawai′I
    Color profile: Generic CMYK printer profile Composite Default screen 988 Subsurface and nighttime behaviour of pantropical spotted dolphins in Hawai′i Robin W. Baird, Allan D. Ligon, Sascha K. Hooker, and Antoinette M. Gorgone Abstract: Pantropical spotted dolphins (Stenella attenuata) are found in both pelagic waters and around oceanic is- lands. A variety of differences exist between populations in these types of areas, including average group sizes, extent of movements, and frequency of multi-species associations. Diving and nighttime behaviour of pantropical spotted dolphins were studied near the islands of Maui and Lana′i, Hawai′i, in 1999. Suction-cup-attached time–depth recorder/VHF-radio tags were deployed on six dolphins for a total of 29 h. Rates of movements of tagged dolphins were substantially lower than reported in pelagic waters. Average diving depths and durations were shallower and shorter than reported for other similar-sized odontocetes but were similar to those reported in a study of pantropical spotted dolphins in the pelagic waters of the eastern tropical Pacific. Dives (defined as >5 m deep) at night were deeper (mean = 57.0 m, SD = 23.5 m, n = 2 individuals, maximum depth 213 m) than during the day (mean = 12.8 m, SD = 2.1 m, n = 4 individuals, maximum depth 122 m), and swim velocity also increased after dark. These results, together with the series of deep dives recorded immediately after sunset, suggest that pantropical spotted dolphins around Hawai′i feed primarily at night on organisms associated with the deep-scattering layer as it rises up to the surface after dark.
    [Show full text]