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A New Giant Petrel (Macronectes, Aves: Procellariidae) from the Pliocene of Taranaki, New Zealand †. TAXONOMY 2023. [DOI: 10.3390/taxonomy3010006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A new species of giant petrel, Macronectes tinae sp. nov., is described from the Pliocene deposits of South Taranaki, New Zealand. The holotype is a near complete skull and the paratype a fragmentary left humerus; both come from the Tangahoe Formation, dating from the late Pliocene (Piacenzian or “Waipipian”; age estimated as ca. 3.36–3.06 Ma). The new species of giant petrel is the first fossil Macronectes ever reported. It is morphologically similar to the two present-day Macronectes spp., but it was a smaller bird. The skull is diagnosed by its overall smaller size, a proportionately longer apertura nasi ossea, and potentially by a shorter os supraocciptale. The humerus is diagnosed from both species by a proportionately less deep shaft, a more prominent medial portion of the epicondylus ventralis, and a larger and fusiform fossa medialis brachialis. The Tangahoe Formation is proving to be a remarkable source of marine vertebrate fossils and an important piece of the puzzle in understanding the evolution and biogeography of seabirds.
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Rule JP, Marx FG, Evans AR, Fitzgerald EM, Adams JW. True seals achieved global distribution by breaking Bergmann's rule. Evolution 2022; 76:1260-1286. [PMID: 35404473 PMCID: PMC9321958 DOI: 10.1111/evo.14488] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 02/18/2022] [Accepted: 03/16/2022] [Indexed: 01/21/2023]
Abstract
True seals (phocids) have achieved a global distribution by crossing the equator multiple times in their evolutionary history. This is remarkable, as warm tropical waters are regarded as a barrier to marine mammal dispersal and-following Bergmann's rule-may have limited crossings to small-bodied species only. Here, we show that ancestral phocids were medium sized and did not obviously follow Bergmann's rule. Instead, they ranged across a broad spectrum of environmental temperatures, without undergoing shifts in temperature- or size-related evolutionary rates following dispersals across the equator. We conclude that the tropics have not constrained phocid biogeography.
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Affiliation(s)
- James P. Rule
- Department of Anatomy and Developmental Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVIC3800Australia,GeosciencesMuseums VictoriaMelbourneVIC3001Australia
| | - Felix G. Marx
- Museum of New Zealand Te Papa TongarewaWellington6011New Zealand,Department of GeologyUniversity of OtagoDunedin9016New Zealand
| | - Alistair R. Evans
- GeosciencesMuseums VictoriaMelbourneVIC3001Australia,School of Biological SciencesMonash UniversityMelbourneVIC3800Australia
| | - Erich M.G. Fitzgerald
- GeosciencesMuseums VictoriaMelbourneVIC3001Australia,School of Biological SciencesMonash UniversityMelbourneVIC3800Australia,National Museum of Natural HistorySmithsonian InstitutionWashington, D.C.20013,Department of Life SciencesNatural History MuseumLondonSW7 5BDUnited Kingdom
| | - Justin W. Adams
- Department of Anatomy and Developmental Biology, Biomedicine Discovery InstituteMonash UniversityClaytonVIC3800Australia,GeosciencesMuseums VictoriaMelbourneVIC3001Australia
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3
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Lopes F, Oliveira LR, Kessler A, Beux Y, Crespo E, Cárdenas-Alayza S, Majluf P, Sepúlveda M, Brownell RL, Franco-Trecu V, Páez-Rosas D, Chaves J, Loch C, Robertson BC, Acevedo-Whitehouse K, Elorriaga-Verplancken FR, Kirkman SP, Peart CR, Wolf JBW, Bonatto SL. Phylogenomic Discordance in the Eared Seals is best explained by Incomplete Lineage Sorting following Explosive Radiation in the Southern Hemisphere. Syst Biol 2020; 70:786-802. [PMID: 33367817 DOI: 10.1093/sysbio/syaa099] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 12/02/2020] [Accepted: 12/08/2020] [Indexed: 12/25/2022] Open
Abstract
The phylogeny and systematics of fur seals and sea lions (Otariidae) have long been studied with diverse data types, including an increasing amount of molecular data. However, only a few phylogenetic relationships have reached acceptance because of strong gene-tree species tree discordance. Divergence times estimates in the group also vary largely between studies. These uncertainties impeded the understanding of the biogeographical history of the group, such as when and how trans-equatorial dispersal and subsequent speciation events occurred. Here, we used high-coverage genome-wide sequencing for 14 of the 15 species of Otariidae to elucidate the phylogeny of the family and its bearing on the taxonomy and biogeographical history. Despite extreme topological discordance among gene trees, we found a fully supported species tree that agrees with the few well-accepted relationships and establishes monophyly of the genus Arctocephalus. Our data support a relatively recent trans-hemispheric dispersal at the base of a southern clade, which rapidly diversified into six major lineages between 3 and 2.5 Ma. Otaria diverged first, followed by Phocarctos and then four major lineages within Arctocephalus. However, we found Zalophus to be nonmonophyletic, with California (Zalophus californianus) and Steller sea lions (Eumetopias jubatus) grouping closer than the Galapagos sea lion (Zalophus wollebaeki) with evidence for introgression between the two genera. Overall, the high degree of genealogical discordance was best explained by incomplete lineage sorting resulting from quasi-simultaneous speciation within the southern clade with introgresssion playing a subordinate role in explaining the incongruence among and within prior phylogenetic studies of the family. [Hybridization; ILS; phylogenomics; Pleistocene; Pliocene; monophyly.].
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Affiliation(s)
- Fernando Lopes
- Escola de Ciências da Saúde e da Vida, Pontifícia Universidade Católica do Rio Grande do Sul, 90619-900 Porto Alegre, RS, Brazil.,Laboratório de Ecologia de Mamíferos, Universidade do Vale do Rio dos Sinos, São Leopoldo, RS, Brazil
| | - Larissa R Oliveira
- Laboratório de Ecologia de Mamíferos, Universidade do Vale do Rio dos Sinos, São Leopoldo, RS, Brazil.,GEMARS, Grupo de Estudos de Mamíferos Aquáticos do Rio Grande do Sul, 95560-000 Torres, RS, Brazil
| | - Amanda Kessler
- Escola de Ciências da Saúde e da Vida, Pontifícia Universidade Católica do Rio Grande do Sul, 90619-900 Porto Alegre, RS, Brazil
| | - Yago Beux
- Escola de Ciências da Saúde e da Vida, Pontifícia Universidade Católica do Rio Grande do Sul, 90619-900 Porto Alegre, RS, Brazil
| | - Enrique Crespo
- Centro Nacional Patagónico - CENPAT, CONICET, Puerto Madryn, Argentina
| | - Susana Cárdenas-Alayza
- Centro para la Sostenibilidad Ambiental, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Patricia Majluf
- Centro para la Sostenibilidad Ambiental, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Maritza Sepúlveda
- Centro de Investigación y Gestión de Recursos Naturales (CIGREN), Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Robert L Brownell
- Southwest Fisheries Science Center, National Oceanic and Atmospheric Administration, NOAA, La Jolla, USA
| | - Valentina Franco-Trecu
- Departamento de Ecología y Evolución, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Diego Páez-Rosas
- Colegio de Ciencias Biológicas y Ambientales, COCIBA, Universidad San Francisco de Quito, Quito, Ecuador
| | - Jaime Chaves
- Colegio de Ciencias Biológicas y Ambientales, COCIBA, Universidad San Francisco de Quito, Quito, Ecuador.,Department of Biology, San Francisco State University, 1800 Holloway Ave, San Francisco, CA, USA
| | - Carolina Loch
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, Dunedin, New Zealand
| | | | - Karina Acevedo-Whitehouse
- Unit for Basic and Applied Microbiology, School of Natural Sciences, Universidad Autónoma de Querétaro, Querétaro, Mexico
| | | | - Stephen P Kirkman
- Department of Environmental Affairs, Oceans and Coasts, Cape Town, South Africa
| | - Claire R Peart
- Department Biologie II, Division of Evolutionary Biology, Ludwig-Maximilians-Universität München, Münich, Germany
| | - Jochen B W Wolf
- Department Biologie II, Division of Evolutionary Biology, Ludwig-Maximilians-Universität München, Münich, Germany
| | - Sandro L Bonatto
- Escola de Ciências da Saúde e da Vida, Pontifícia Universidade Católica do Rio Grande do Sul, 90619-900 Porto Alegre, RS, Brazil
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Rule JP, Adams JW, Marx FG, Evans AR, Tennyson AJD, Scofield RP, Fitzgerald EMG. First monk seal from the Southern Hemisphere rewrites the evolutionary history of true seals. Proc Biol Sci 2020; 287:20202318. [PMID: 33171079 DOI: 10.1098/rspb.2020.2318] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Living true seals (phocids) are the most widely dispersed semi-aquatic marine mammals, and comprise geographically separate northern (phocine) and southern (monachine) groups. Both are thought to have evolved in the North Atlantic, with only two monachine lineages-elephant seals and lobodontins-subsequently crossing the equator. The third and most basal monachine tribe, the monk seals, have hitherto been interpreted as exclusively northern and (sub)tropical throughout their entire history. Here, we describe a new species of extinct monk seal from the Pliocene of New Zealand, the first of its kind from the Southern Hemisphere, based on one of the best-preserved and richest samples of seal fossils worldwide. This unanticipated discovery reveals that all three monachine tribes once coexisted south of the equator, and forces a profound revision of their evolutionary history: rather than primarily diversifying in the North Atlantic, monachines largely evolved in the Southern Hemisphere, and from this southern cradle later reinvaded the north. Our results suggest that true seals crossed the equator over eight times in their history. Overall, they more than double the age of the north-south dichotomy characterizing living true seals and confirms a surprisingly recent major change in southern phocid diversity.
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Affiliation(s)
- James P Rule
- Department of Anatomy and Developmental Biology, Victoria 3800, Australia.,Geosciences, Museums Victoria, Melbourne, Victoria 3001, Australia
| | - Justin W Adams
- Department of Anatomy and Developmental Biology, Victoria 3800, Australia
| | - Felix G Marx
- Museum of New Zealand Te Papa Tongarewa, Wellington 6011, New Zealand.,Department of Geology, University of Otago, Dunedin 9016, New Zealand
| | - Alistair R Evans
- School of Biological Sciences, Monash University, Victoria 3800, Australia.,Geosciences, Museums Victoria, Melbourne, Victoria 3001, Australia
| | - Alan J D Tennyson
- Museum of New Zealand Te Papa Tongarewa, Wellington 6011, New Zealand
| | | | - Erich M G Fitzgerald
- School of Biological Sciences, Monash University, Victoria 3800, Australia.,Geosciences, Museums Victoria, Melbourne, Victoria 3001, Australia.,National Museum of Natural History, Smithsonian Institution, Washington DC 20013-7012, USA
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Rule JP, Adams JW, Fitzgerald EMG. Colonization of the ancient southern oceans by small-sized Phocidae: new evidence from Australia. Zool J Linn Soc 2020. [DOI: 10.1093/zoolinnean/zlaa075] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Abstract
Most of the diversity of extant southern true seals (Phocidae: Monachinae) is present in the Southern Ocean, but a poor fossil record means that the origin of this fauna remains unknown. Australia represents a large gap in the record bordering the Southern Ocean that could possibly inform on the origins of the extant Antarctic monachines, with most known fossils remaining undescribed. Here we describe the oldest Australian fossil pinniped assemblage, from the Late Miocene to the Early Pliocene of Beaumaris. Two fossils are referrable to Pinnipedia, five (possibly six) to Phocidae and a humerus is referrable to Monachinae. The humerus is not referrable to any extant tribe, potentially representing an archaic monachine. The description of this assemblage is consistent with the Neogene pinniped fauna of Australia being exclusively monachine before the arrival of otariids (fur seals and sea lions). The Beaumaris humerus, along with other Neogene phocids from the Southern Ocean margins, were smaller than their extant Antarctic relatives, possibly driven by longer food chains with less energy efficiency between trophic levels. This suggests that small archaic phocids potentially used the Southern Ocean as a means of dispersal before the arrival of extant Antarctic monachines.
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Affiliation(s)
- James P Rule
- Department of Anatomy and Developmental Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
- Vertebrate Palaeontology, Museums Victoria, Melbourne, Victoria, Australia
| | - Justin W Adams
- Department of Anatomy and Developmental Biology, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Erich M G Fitzgerald
- Vertebrate Palaeontology, Museums Victoria, Melbourne, Victoria, Australia
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
- National Museum of Natural History, Smithsonian Institution, Washington DC, USA
- Department of Life Sciences, Natural History Museum, London, UK
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Dewaele L, Lambert O, Louwye S. A critical revision of the fossil record, stratigraphy and diversity of the Neogene seal genus Monotherium (Carnivora, Phocidae). ROYAL SOCIETY OPEN SCIENCE 2018; 5:171669. [PMID: 29892365 PMCID: PMC5990722 DOI: 10.1098/rsos.171669] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 04/03/2018] [Indexed: 05/24/2023]
Abstract
Historically, Monotherium had been one of the few genera of extinct Phocidae (true seals) that served as a wastebin taxon. Consequently, it did neither aid in understanding phylogenetic relationships of extinct Phocidae, nor in understanding seal diversity in deep time. This urged the reassessment of the genus. Before our review, Monotherium included five different species: Monotherium aberratum, Monotherium affine, and Monotherium delognii from Belgium; Monotherium gaudini from Italy; and Monotherium? wymani from the east coast USA. In this work we redescribe the fossil record of the genus, retaining the type species M. delognii. Monotherium aberratum and M. affine are reassigned to the new phocine genus Frisiphoca. Monotherium gaudini is renamed and considered a stem-monachine (Noriphoca gaudini). The holotype of the monachine M.? wymani requires further study pending the discovery of new fossil material that could be attributed to the same taxon. Reinvestigating the stratigraphic context reveals that N. gaudini most likely represents one of the two oldest named phocid seals, or even the oldest, dated to the late Oligocene-earliest Miocene. Our results allow questioning the widespread idea that Phocidae originated in the western Atlantic and better appreciate their palaeobiogeography during the late Oligocene-Miocene interval in the North Atlantic realm.
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Affiliation(s)
- Leonard Dewaele
- Department of Geology, Ghent University, Ghent, Belgium
- ‘Earth and History of Life’, Royal Belgian Institute of Natural Sciences, Brussels, Belgium
| | - Olivier Lambert
- ‘Earth and History of Life’, Royal Belgian Institute of Natural Sciences, Brussels, Belgium
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Dewaele L, Amson E, Lambert O, Louwye S. Reappraisal of the extinct seal " Phoca" vitulinoides from the Neogene of the North Sea Basin, with bearing on its geological age, phylogenetic affinities, and locomotion. PeerJ 2017; 5:e3316. [PMID: 28533965 PMCID: PMC5436577 DOI: 10.7717/peerj.3316] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Accepted: 04/14/2017] [Indexed: 11/30/2022] Open
Abstract
Background Discovered on the southern margin of the North Sea Basin, “Phoca” vitulinoides represents one of the best-known extinct species of Phocidae. However, little attention has been given to the species ever since its original 19th century description. Newly discovered material, including the most complete specimen of fossil Phocidae from the North Sea Basin, prompted the redescription of the species. Also, the type material of “Phoca” vitulinoides is lost. Methods “Phoca” vitulinoides is redescribed. Its phylogenetic position among Phocinae is assessed through phylogenetic analysis. Dinoflagellate cyst biostratigraphy is used to determine and reassess the geological age of the species. Myological descriptions of extant taxa are used to infer muscle attachments, and basic comparative anatomy of the gross morphology and biomechanics are applied to reconstruct locomotion. Results Detailed redescription of “Phoca” vitulinoides indicates relatively little affinities with the genus Phoca, but rather asks for the establishment of a new genus: Nanophoca gen. nov. Hence, “Phoca” vitulinoides is recombined into Nanophoca vitulinoides. This reassignment is confirmed by the phylogenetic analysis, grouping the genus Nanophoca and other extinct phocine taxa as stem phocines. Biostratigraphy and lithostratigraphy expand the known stratigraphic range of N. vitulinoides from the late Langhian to the late Serravallian. The osteological anatomy of N. vitulinoides indicates a relatively strong development of muscles used for fore flipper propulsion and increased flexibility for the hind flipper. Discussion The extended stratigraphic range of N. vitulinoides into the middle Miocene confirms relatively early diversification of Phocinae in the North Atlantic. Morphological features on the fore- and hindlimb of the species point toward an increased use of the fore flipper and greater flexibility of the hind flipper as compared to extant Phocinae, clearly indicating less derived locomotor strategies in this Miocene phocine species. Estimations of the overall body size indicate that N. vitulinoides is much smaller than Pusa, the smallest extant genus of Phocinae (and Phocidae), and than most extinct phocines.
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Affiliation(s)
- Leonard Dewaele
- Department of Geology, Ghent University, Ghent, Belgium.,O.D. Earth and History of Life, Royal Belgian Institute of Natural Sciences, Brussels, Belgium
| | - Eli Amson
- Arbeitsgruppe Morphologie und Formengeschichte, Humboldt Universität Berlin, Berlin, Germany.,Paläontologisches Institut und Museum, University of Zürich, Zürich, Switzerland
| | - Olivier Lambert
- O.D. Earth and History of Life, Royal Belgian Institute of Natural Sciences, Brussels, Belgium
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Dewaele L, Lambert O, Louwye S. On Prophoca and Leptophoca (Pinnipedia, Phocidae) from the Miocene of the North Atlantic realm: redescription, phylogenetic affinities and paleobiogeographic implications. PeerJ 2017; 5:e3024. [PMID: 28243538 PMCID: PMC5322758 DOI: 10.7717/peerj.3024] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 01/24/2017] [Indexed: 11/20/2022] Open
Abstract
Background Prophoca and Leptophoca represent the oldest known genera of phocine seals, dating from the latest early to middle Miocene. Originally, Prophoca rousseaui and Prophoca proxima were described based on fragmentary remains from the Miocene of Belgium. However, several researchers contested the union of Prophoca rousseaui and Prophoca proxima into one genus, without providing evidence. The stratigraphic context of Prophoca remained poorly constrained due to the lack of precise data associated with the original specimens collected in the area of Antwerp (north of Belgium). Methods Prophoca and Leptophoca are redescribed and their phylogenetic position among Phocidae is reassessed using PAUP. Dinoflagellate biostratigraphy has been carried out on sediment samples associated with specimens from Prophoca and Leptophoca to elucidate their approximate ages. Results Whereas the species Prophoca rousseaui is redescribed, Prophoca proxima is considered synonymous to Leptophoca lenis, with the proposal of a new combination Leptophoca proxima (Van Beneden, 1877). Sediment samples from specimens of both taxa have been dated to the late Langhian–early Serravallian (middle Miocene). Following a reinvestigation of Leptophoca amphiatlantica, characters from the original diagnosis are questioned and the specimens of Leptophoca amphiatlantica are considered Leptophoca cf. L. proxima. In a phylogenetic analysis, Prophoca rousseaui and Leptophoca proxima constitute early branching stem-phocines. Discussion Leptophoca proxima from the North Sea Basin is younger than the oldest known find of Leptophoca proxima from North America, which does not contradict the hypothesis that Phocinae originated along the east coast of North America during the late early Miocene, followed by dispersal to Europe shortly after. Morphological features of the appendicular skeleton indicate that Prophoca rousseaui and Leptophoca proxima have archaic locomotory modes, retaining a more prominent use of the fore flipper for aquatic propulsion than extant Phocidae.
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Affiliation(s)
- Leonard Dewaele
- Department of Geology, Ghent University, Ghent, Belgium; O.D. Earth and History of Life, Royal Belgian Institute of Natural Sciences, Brussels, Belgium
| | - Olivier Lambert
- O.D. Earth and History of Life, Royal Belgian Institute of Natural Sciences , Brussels , Belgium
| | - Stephen Louwye
- Department of Geology, Ghent University , Ghent , Belgium
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Abstract
Abstract This study forms part of a larger project to reconstruct the Mio-Pliocene marine palaeoenvironment along South Africa’s west coast. It documents the shark–cetacean trophic interaction during the Zanclean (5 Ma) at Duinefontein (Koeberg). The damage described on the fragmentary cetacean bones was compared with similar damage observed on fossils from Langebaanweg, a Mio-Pliocene site on the west coast of South Africa, and data present in the literature. This comparison showed that the damage was the result of shark bites. The state of preservation makes it difficult to determine if the shark bite marks were the cause of death or as a result of scavenging. The presence of the bite marks on the bone would, however, indicate some degree of skeletonisation. Bite marks on some cranial fragments would suggest that the cetacean’s body was in an inverted position typical of a floating carcass. The preservation of the material suggests that the bones were exposed to wave action resulting in their fragmentation as well as abrasion, polishing and rolling. It also suggests that the cetacean skeletons were exposed for a long time prior to burial. The morphology of the bites suggests that the damage was inflicted by sharks with serrated and unserrated teeth. Shark teeth collected from the deposit include megalodon (Carcharodon megalodon), white (Carcharodon carcharias) as well as mako (Isurus sp. and Cosmopolitodus hastalis) sharks, making these sharks the most likely predators/scavengers.
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Churchill M, Clementz MT, Kohno N. Cope's rule and the evolution of body size in Pinnipedimorpha (Mammalia: Carnivora). Evolution 2014; 69:201-15. [PMID: 25355195 DOI: 10.1111/evo.12560] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 10/20/2014] [Indexed: 11/28/2022]
Abstract
Cope's rule describes the evolutionary trend for animal lineages to increase in body size over time. In this study, we tested the validity of Cope's rule for a marine mammal clade, the Pinnipedimorpha, which includes the extinct Desmatophocidae, and extant Phocidae (earless seals), Otariidae (fur seals and sea lions), and Odobenidae (walruses). We tested for the presence of Cope's rule by compiling a large dataset of body size data for extant and fossil pinnipeds and then examined how body size evolved through time. We found that there was a positive relationship between geologic age and body size. However, this trend is the result of differences between early assemblages of small-bodied pinnipeds (Oligocene to early Miocene) and later assemblages (middle Miocene to Pliocene) for which species exhibited greater size diversity. No significant differences were found between the number of increases or decreases in body size within Pinnipedimorpha or within specific pinniped clades. This suggests that the pinniped body size increase was driven by passive diversification into vacant niche space, with the common ancestor of Pinnipedimorpha occurring near the minimum adult body size possible for a marine mammal. Based upon the above results, the evolutionary history of pinnipeds does not follow Cope's rule.
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Affiliation(s)
- Morgan Churchill
- Department of Geology and Geophysics, University of Wyoming, Laramie, Wyoming, 8207; Program in Ecology, University of Wyoming, Laramie, Wyoming, 82071.
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11
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Churchill M, Boessenecker RW, Clementz MT. Colonization of the Southern Hemisphere by fur seals and sea lions (Carnivora: Otariidae) revealed by combined evidence phylogenetic and Bayesian biogeographical analysis. Zool J Linn Soc 2014. [DOI: 10.1111/zoj.12163] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Morgan Churchill
- Department of Geology and Geophysics; University of Wyoming; Dept. 3006; 1000 E. University Ave. Laramie WY 82071 USA
- Program in Ecology; University of Wyoming; Berry Center 231; 1000 E. University Ave. Laramie WY 82071 USA
| | - Robert W. Boessenecker
- Department of Geology; University of Otago; P.O. Box 56 Dunedin 9054 New Zealand
- University of California Museum of Paleontology; University of California; 1101 Valley Life Sciences Building Berkeley CA 94720 USA
| | - Mark T. Clementz
- Department of Geology and Geophysics; University of Wyoming; Dept. 3006; 1000 E. University Ave. Laramie WY 82071 USA
- Program in Ecology; University of Wyoming; Berry Center 231; 1000 E. University Ave. Laramie WY 82071 USA
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Chávez Hoffmeister M, Carrillo Briceño JD, Nielsen SN. The evolution of seabirds in the Humboldt Current: new clues from the Pliocene of Central Chile. PLoS One 2014; 9:e90043. [PMID: 24621560 PMCID: PMC3951197 DOI: 10.1371/journal.pone.0090043] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Accepted: 01/28/2014] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND During the last decade, new Neogene fossil assemblages from South America have revealed important clues about the evolution of seabird faunas in one of the major upwelling systems of the world: the Humboldt Current. However, most of this record comes from arid Northern Chile and Southern Peru and, in consequence, our knowledge of the evolutionary history of seabirds in the temperate transitional zone is negligible. A new Late Pliocene assemblage of fossil birds from the coastal locality of Horcon in Central Chile offers a unique opportunity to fill this gap. PRINCIPAL FINDINGS Isolated bones of a medium-sized penguin are the most abundant bird remains. Morphological and cladistic analyses reveal that these specimens represent a new species of crested penguin, Eudyptes calauina sp. nov. Eudyptes is a penguin genus that inhabit temperate and subantarctic regions and currently absent in central Chile. Additionally, a partial skeleton of a small species of cormorant and a partial tarsometatarsus of a sooty shearwater have been identified. CONCLUSION/SIGNIFICANCE The Horcon fossils suggest the existence of a mixed avifauna in central Chile during the Pliocene in concordance with the latitudinal thermal gradient. This resembles the current assemblages from the transitional zone, with the presence of species shared with Northern Chile and Southern Peru and a previously unrecorded penguin currently absent from the Humboldt System but present in the Magellanic region. Comparison of Pliocene seabird diversity across the Pacific coast of South America shows that the Horcon avifauna represents a distinctive assemblage linking the living faunas with the Late Miocene ones. A comparison with the fossil record near the Benguela Current (west coast of southern Africa) suggests that the thermic gradient could play an important role in the preservation of a higher diversity of cold/temperate seabirds in the Humboldt Current.
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Affiliation(s)
- Martín Chávez Hoffmeister
- School of Earth Sciences, University of Bristol, Bristol, United Kingdom
- Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile
| | | | - Sven N. Nielsen
- Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile
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Affiliation(s)
- Daniel B. Thomas
- Department of Vertebrate Zoology; National Museum of Natural History; Smithsonian Institution; Washington, DC 20013 USA
| | - Daniel T. Ksepka
- Department of Marine, Earth, and Atmospheric Sciences; North Carolina State University; Campus Box 8208 Raleigh NC 27695 USA
- Department of Paleontology; North Carolina Museum of Natural Sciences; Raleigh NC 27601 USA
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