New Late Miocene Dromomerycine Artiodactyl from the Amazon Basin: Implications for Interchange Dynamics

2014 ◽  
Vol 88 (3) ◽  
pp. 434-443 ◽  
Author(s):  
Donald R. Prothero ◽  
Kenneth E. Campbell ◽  
Brian L. Beatty ◽  
Carl D. Frailey
Keyword(s):  
North America ◽  
South America ◽  
Late Miocene ◽  
Amazon Basin ◽  
New Taxon ◽  
Isthmus Of Panama ◽  
Great American Biotic Interchange ◽  
American Immigrant ◽  
Early Late ◽  
Ground Sloths

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.

scholarly journals Amazonia as the Origin and Diversification Area of Didelphidae (Mammalia: Metatheria), and a Review of the Fossil Record of the Clade

2021 ◽  
Author(s):  
Mariela C. Castro ◽  
Murilo J. Dahur ◽  
Gabriel S. Ferreira
Keyword(s):  
South America ◽  
Amazon Basin ◽  
Parametric Models ◽  
Isthmus Of Panama ◽  
Biogeographic History ◽  
Early Diversification ◽  
Northern Portion ◽  
History Of ◽  
Environmental Events ◽  
Fossil Records

AbstractDidelphidae is the largest New World radiation of marsupials, and is mostly represented by arboreal, small- to medium-sized taxa that inhabit tropical and/or subtropical forests. The group originated and remained isolated in South America for millions of years, until the formation of the Isthmus of Panama. In this study, we present the first reconstruction of the biogeographic history of Didelphidae including all major clades, based on parametric models and stratified analyses over time. We also compiled all the pre-Quaternary fossil records of the group, and contrasted these data to our biogeographic inferences, as well as to major environmental events that occurred in the South American Cenozoic. Our results indicate the relevance of Amazonia in the early diversification of Didelphidae, including the divergence of the major clades traditionally ranked as subfamilies and tribes. Cladogeneses in other areas started in the late Miocene, an interval of intense shifts, especially in the northern portion of Andes and Amazon Basin. Occupation of other areas continued through the Pliocene, but few were only colonized in Quaternary times. The comparison between the biogeographic inference and the fossil records highlights some further steps towards better understanding the spatiotemporal evolution of the clade. Finally, our results stress that the early history of didelphids is obscured by the lack of Paleogene fossils, which are still to be unearthed from low-latitude deposits of South America.

scholarly journals Migration of exotic species of ammonites during highstands of sea level

1992 ◽  
Vol 6 ◽  
pp. 324-324
Author(s):  
Keith Young
Keyword(s):  
North America ◽  
South America ◽  
Exotic Species ◽  
Sea Level ◽  
South Atlantic ◽  
Horn Of Africa ◽  
Mozambique Channel ◽  
The North ◽  
North And South ◽  
Early Late

In northeastern Chihuahua and Trans-Pecos Texas, in the early Late Albian zone of Hysteroceras varicosum occurs the Boeseites romeri (Haas) fauna with B. romeri (Hass), B. perarmata (Hass), B. aff. barbouri (Haas), B. cf. howelli (Haas), B.proteus (Haas), Prohysteroceras cf. P. hanhaense Haas, Elobiceras sp., and Dipoloceras (?) sp. B. perarmata has also been collected at Cerro Mercado, near Monclova, Coahuila. Haas originally described this fauna from Angola. Now, from rocks in the same zone in the Sierra Mojada, Coahuila, Mexico, there is a form related to if not identical with Hysteroceras famelicum Van Hoepen, also originally described from Angola and also from the zone of Hysteroceras varicosum.These fossils are known only from southern North America and Angola; they have not been described from the European Tethys. In 1984 I suggested that during the highstand of sea level of the early Late Albian (Hysteroceras varicosum zone) these ammonites migrated from Angola to Mexico and Trans-Pecos Texas via an epeiric seaway extending across the sag between South America and Africa proposed by Kennedy and Cooper. This would be twelve to fifteen million years prior to an oceanic connection between the North and South Atlantic.I would now ask, can similar epeiric seas and highstands of sea level explain the migration of successive European, Tethyan, Jurassic ammonite faunas down the Mozambique Channel and around the horn of Africa into the Neuquen Basin of Argentina before Africa and Antarctica separated, as proposed by Spath.

scholarly journals A new enigmatic Late Miocene mylodontoid sloth from northern South America

2015 ◽  
Vol 2 (2) ◽  
pp. 140256 ◽  
Author(s):  
Ascanio D. Rincón ◽  
H. Gregory McDonald ◽  
Andrés Solórzano ◽  
Mónica Núñez Flores ◽  
Damián Ruiz-Ramoni
Keyword(s):  
South America ◽  
Late Miocene ◽  
Preliminary Analysis ◽  
New Genus ◽  
New Taxon ◽  
New Genus And Species ◽  
Consensus Tree ◽  
Discriminate Analysis ◽  
Northern South America ◽  
Phylogenetic Affinities

A new genus and species of sloth ( Eionaletherium tanycnemius gen. et sp. nov.) recently collected from the Late Miocene Urumaco Formation, Venezuela (northern South America) is herein described based on a partial skeleton including associated femora and tibiae. In order to make a preliminary analysis of the phylogenetic affinities of this new sloth we performed a discriminate analysis based on several characters of the femur and tibia of selected Mylodontoidea and Megatherioidea sloths. The consensus tree produced indicates that the new sloth, E. tanycnemius , is a member of the Mylodontoidea. Surprisingly, the new taxon shows some enigmatic features among Neogene mylodontoid sloths, e.g. femur with a robust lesser trochanter that projects medially and the straight distinctly elongated tibia. The discovery of E. tanycnemius increases the diversity of sloths present in the Urumaco sequence to ten taxa. This taxon supports previous studies of the sloth assemblage from the Urumaco sequence as it further indicates that there are several sloth lineages present that are unknown from the better sampled areas of southern South America.

scholarly journals A close relative of the Amazon river dolphin in marine deposits: a new Iniidae from the late Miocene of Angola

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5556 ◽  
Author(s):  
Olivier Lambert ◽  
Camille Auclair ◽  
Cirilo Cauxeiro ◽  
Michel Lopez ◽  
Sylvain Adnet
Keyword(s):  
South America ◽  
Late Miocene ◽  
South Atlantic ◽  
Eastern Coast ◽  
Amazon River ◽  
New Taxon ◽  
River Dolphin ◽  
Marine Deposits ◽  
Extant Species ◽  
Inia Geoffrensis

Background A few odontocetes (echolocating toothed cetaceans) have been able to independently colonize freshwater ecosystems. Although some extant species of delphinids (true dolphins) and phocoenids (porpoises) at least occasionally migrate upstream of large river systems, they have close relatives in fully marine regions. This contrasts with the three odontocete families only containing extant species with a strictly freshwater habitat (Iniidae in South America, the recently extinct Lipotidae in China, and Platanistidae in southeast Asia). Among those, the fossil record of Iniidae includes taxa from freshwater deposits of South America, partly overlapping geographically with the extant Amazon river dolphin Inia geoffrensis, whereas a few marine species from the Americas were only tentatively referred to the family, leaving the transition from a marine to freshwater environment poorly understood. Methods Based on a partial odontocete skeleton including the cranium, discovered in late Miocene (Tortonian-Messinian) marine deposits near the estuary of the Cuanza River, Angola, we describe a new large iniid genus and species. The new taxon is compared to other extinct and extant iniids, and its phylogenetic relationships with the latter are investigated through cladistic analysis. Results and Discussion The new genus and species Kwanzacetus khoisani shares a series of morphological features with Inia geoffrensis, including the combination of a frontal boss with nasals being lower on the anterior wall of the vertex, the laterally directed postorbital process of the frontal, the anteroposterior thickening of the nuchal crest, and robust teeth with wrinkled enamel. As confirmed (although with a low support) with the phylogenetic analysis, this makes the new taxon the closest relative of I. geoffrensis found in marine deposits. The geographic provenance of K. khoisani, on the eastern coast of South Atlantic, suggests that the transition from the marine environment to a freshwater, Amazonian habitat may have occurred on the Atlantic side of South America. This new record further increases the inioid diversity during the late Miocene, a time interval confirmed here as the heyday for this superfamily. Finally, this first description of a Neogene cetacean from inland deposits of western sub-Saharan Africa reveals the potential of this large coastal area for deciphering key steps of the evolutionary history of modern cetaceans in the South Atlantic.

Trends in Distance Education in South America

2011 ◽  
pp. 2146-2154
Author(s):  
Luis Barrera
Keyword(s):  
Distance Education ◽  
Developing Countries ◽  
North America ◽  
South America ◽  
Development Programme ◽  
Western Hemisphere ◽  
South American ◽  
Future Trends ◽  
Isthmus Of Panama ◽  
Nations Development

This article reviews the history, state of the art, and future trends in distance education, in South American countries, through an overview of the main experiences in the region. South America is in the western hemisphere, connected to Central and North America by the Isthmus of Panama. Twelve countries form this continent: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay and Venezuela. As reported by the United Nations Development Programme (2007), all of them are developing countries, characterized by a difficult social reality as a result of political and economic crisis in the course of its history.

Palaeogene and Neogene brachyurans of the Amazon basin: a revised first appearance date for primary freshwater crabs (Brachyura, Trichodactylidae)

Crustaceana ◽  
2017 ◽  
Vol 90 (7-10) ◽  
pp. 953-967 ◽  
Author(s):  
Sebastian Klaus ◽  
Célio Magalhães ◽  
Rodolfo Salas-Gismondi ◽  
Martin Gross ◽  
Pierre-Olivier Antoine
Keyword(s):  
Late Miocene ◽  
Amazon Basin ◽  
Middle Eocene ◽  
Freshwater Crabs ◽  
Early Oligocene ◽  
The Family ◽  
Continuous Presence ◽  
Early Late ◽  
Amazonian Lowlands

We describe claw fragments of fossil primary freshwater crabs from three areas in the Amazon basin, Tarapoto (Early Oligocene) and Contamana (Middle Eocene to early Late Miocene) in Peru, and Eirunepé (Late Miocene) in Brazil. All these fragments most likely belong to the family Trichodactylidae. We show a continuous presence of primary freshwater crabs in proto-Amazonian lowlands from the Middle Eocene to the Late Miocene and can thus shift the earliest appearance date of freshwater-adapted brachyurans into the Eocene, at least in the Neotropics.

scholarly journals Comparative Assessment and Future Prediction Using CMIP6 and CMIP5 for Annual Precipitation and Extreme Precipitation Simulation

2021 ◽  
Vol 9 ◽  
Author(s):  
Jingjing Li ◽  
Ran Huo ◽  
Hua Chen ◽  
Ying Zhao ◽  
Tianhui Zhao
Keyword(s):  
North America ◽  
South America ◽  
Amazon Basin ◽  
Coupled Model ◽  
Southern South America ◽  
Western Africa ◽  
Precipitation Simulation ◽  
The Future ◽  
Intercomparison Project ◽  
Changing Rate

This study assesses the improvement of the latest Coupled Model Intercomparison Project Phase 6 (CMIP6) over Coupled Model Intercomparison Project Phase 5 (CMIP5) for precipitation simulation. Precipitation simulations under different future climate scenarios are also compared in this work. The results show that: 1) CMIP6 has no overall advantage over CMIP5 in simulating total precipitation (PRCPTOT) and maximum consecutive dry days (CDD). The performance of CMIP6 increases or decreases regionally in PRCPTOT and consecutive dry days. But it is slightly worse than CMIP5 in simulating very wet days (R95pTOT). 2) Comparing the trend test results of CMIP5 and CMIP6 in the future, there are more areas with significant trend based on Mann–Kendall test in CMIP6 compared with that of CMIP5. The differences in PRCPTOT are mainly found in Amazon Basin and Western Africa. The differences between the R95pTOT trends mainly noticeable in South America and Western Africa, and the differences in CDD are mainly reflected in Central Asia, Sahara Desert and central South America. 3) In Southern South America and Western North America, the PRCPTOT changing rate of CMIP6 in the future under various scenarios is always greater than that of CMIP5; in Alaska, Western Africa, Southern Africa, the PRCPTOT changing rate of CMIP6 in the future under various scenarios is always less than that of CMIP5. In Southern South America, the R95pTOT changing rate of CMIP6 in the future under various scenarios is always greater than that of CMIP5; in Alaska, East Asia, North Asia, the R95pTOT changing rate of CMIP6 in the future under various scenarios is always less than that of CMIP5. In almost half of the regions, the CDD changing rate of CMIP6 is less than that of CMIP5 under all scenarios, namely Australia, Amazon Basin, Southern South America, Central America, Western North America, Central North America, Eastern North America, Central Asia, Tibet.

Systematics and paleobiogeography of Sardolagus obscurus n. gen. n. sp. (Leporidae, Lagomorpha) from the early Pleistocene of Sardinia

2018 ◽  
Vol 92 (3) ◽  
pp. 506-522 ◽  
Author(s):  
Chiara Angelone ◽  
Stanislav Čermák ◽  
Blanca Moncunill-Solé ◽  
Josep Quintana ◽  
Caterinella Tuveri ◽  
...  
Keyword(s):  
Phylogenetic Relationship ◽  
Late Pleistocene ◽  
Late Miocene ◽  
Early Pleistocene ◽  
New Taxon ◽  
Late Pliocene ◽  
Phylogenetic Origin ◽  
Middle And Late Pleistocene ◽  
Insular Endemic ◽  
Early Late

AbstractThe extreme rareness of Sardinian fossil sites older than Middle and Late Pleistocene makes the Monte Tuttavista karst complex (E Sardinia, Italy) very important. Remarkable lagomorph material, recovered from several fissure infillings of Monte Tuttavista referable to the Capo Figari/Orosei 1 and Orosei 2 faunal sub-complexes (early Pleistocene, ~2.1/1.9–1.1 Ma), allowed us to describe a new endemic insular leporid, Sardolagus obscurus n. gen. n. sp. The new taxon is characterized by a peculiar combination of an advanced p3 (Lepus-type) and a primitive P2 lacking deep flexa. The origin of such discrepancy, unprecedented among continental and insular endemic European leporids, is unclear. It could be the result of: (1) an independent evolution of p3 from an ancestor bearing the primitive P2/p3 (e.g., Alilepus, Hypolagus), or (2) a selective reversal morphocline from an Oryctolagus/Lepus-like leporine. The lack of data about the phylogenetic origin of the new taxon makes any inference about its possible arrival to Sardinia problematic. Crossing the European leporid records and evidence of migrations to Sardinia, we hypothesize three possible ages in which the ancestor of Sardolagus obscurus could have arrived in Sardinia, restricted to the late Miocene–early/late Pliocene (~8–3.6 Ma). The phylogenetic relationship between Sardolagus obscurus n. gen. n. sp. and the oldest Sardinian leporid, recorded from Capo Mannu D1 and dated at the early/late Pliocene boundary (~3.6 Ma), is unclear at present, however it is quite likely that they pertain to the same lineage.UUID: http://zoobank.org/ca8e0023-7c9d-4b00-a294-d166c37c5c71

A new and most complete pampathere (Mammalia, Xenarthra, Cingulata) from the Quaternary of Bahia, Brazil

Zootaxa ◽  
2019 ◽  
Vol 4661 (3) ◽  
pp. 401-444 ◽  
Author(s):  
JORGE FELIPE MOURA ◽  
FLÁVIO GÓIS ◽  
FERNANDO CARLOS GALLIARI ◽  
MARCELO ADORNA FERNANDES
Keyword(s):  
New Species ◽  
North America ◽  
South America ◽  
Axial Length ◽  
Vertebral Column ◽  
Middle Miocene ◽  
The Other ◽  
South American ◽  
Great American Biotic Interchange ◽  
A New Species

Pampatheriidae is a group of South American native cingulates recorded from the Middle Miocene to the Early Holocene. These animals arrived in North America during the Great American Biotic Interchange. During the Quaternary, at least three genera existed: Tonnicinctus Góis, González Ruiz, Scillato-Yané and Soibelzon, Pampatherium Gervais and Ameghino, and Holmesina Simpson. They are differentiated mainly by craniodental and osteodermal characters. In this paper, we describe a new species of Holmesina from Bahia state, Brazil. Two well-preserved specimens possessing osteoderms associated with their skeletons enabled us to determine the genus and species more reliably. Holmesina cryptae sp. nov. differs from the other Quaternary pampatheres by having the simplest ornamental pattern of osteoderms, sharing characteristics between Pampatherium and Holmesina osteoderms and the most robust skull among the Holmesina species, however preserving the main synapomorphies of the genus. Moreover, the integrity of the remains of H. cryptae sp. nov. enabled us to describe elements of the hyoid apparatus, the clavicle, the entire vertebral column and the pelvis. It was also possible to measure its total axial length (2.2 m) more reliably, which is smaller than previously estimated for other pampatheres. Holmesina cryptae sp. nov. constitutes the sixth species of the genus, and it is the fourth in South America. 

Sign in / Sign up

Export Citation Format

Share Document