Recalibrating the Great American Faunal Interchange

A late Miocene gomphothere from southeastern Peru documents the earliest occurrence of a North American mammal in South America as a result of the Great American Faunal Interchange (GAFI). The gomphothere came from the Ipururo Formation, which underlies the Madre de Dios Formation and is separated f...

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Autor principal: Campbell, Kenneth
Formato: Objeto de conferencia Resumen
Lenguaje:Inglés
Publicado: 2010
Materias:
Ciencias Naturales
Paleontología
Great American Faunal Interchange
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/16827
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-16827
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Ciencias Naturales
Paleontología
Great American Faunal Interchange
spellingShingle Ciencias Naturales
Paleontología
Great American Faunal Interchange
Campbell, Kenneth
Recalibrating the Great American Faunal Interchange
topic_facet Ciencias Naturales
Paleontología
Great American Faunal Interchange
description A late Miocene gomphothere from southeastern Peru documents the earliest occurrence of a North American mammal in South America as a result of the Great American Faunal Interchange (GAFI). The gomphothere came from the Ipururo Formation, which underlies the Madre de Dios Formation and is separated from it by the Pan- Amazonian Ucayali Unconformity. The Madre de Dios Formation is dated to 9.5-3.0 Ma using 40Ar/39Ar dates on two volcanic ashes, in combination with magnetostratigraphy. The basal horizon of the Madre de Dios Formation is often fossiliferous, containing many fossil vertebrates typical of the Chasicoan (12-9 Ma) and Huayquerian (9-6 Ma) SALMAs. Also occurring in this horizon are other North American mammals, including other gomphotheres, tapirs, and two genera of extinct peccaries. The presence of this suite of North American mammals in South America in the late Miocene is recognized as the first pulse of the GAFI. Although the well-known swimming ability of elephantoids might have facilitated their very early (~10+ Ma) dispersal to South America, geologic data are now available that indicate the presence of a terrestrial pathway connecting North and South America in the late Miocene. This pathway led from central Panama, where North American mammals are found in early Miocene deposits, through mountainous terrain of the Panama-Costa Rica arc prior to this allochthonous terrain being completely sutured onto western Colombia. Late Miocene ground sloths found in North America probably traveled this route as well. Sea level fluctuations might have served to pulse interchange events until a permanent terrestrial link was established at ~5.0 Ma. That the GAFI began in earnest via terrestrial links in the late Miocene is supported by new data derived from paleontological discoveries, paleoceanographic research, and molecular divergence time estimates. The presence of such a terrestrial link has implications for many fields of scientific endeavor.
format Objeto de conferencia
Resumen
author Campbell, Kenneth
author_facet Campbell, Kenneth
author_sort Campbell, Kenneth
title Recalibrating the Great American Faunal Interchange
title_short Recalibrating the Great American Faunal Interchange
title_full Recalibrating the Great American Faunal Interchange
title_fullStr Recalibrating the Great American Faunal Interchange
title_full_unstemmed Recalibrating the Great American Faunal Interchange
title_sort recalibrating the great american faunal interchange
publishDate 2010
url http://sedici.unlp.edu.ar/handle/10915/16827
work_keys_str_mv AT campbellkenneth recalibratingthegreatamericanfaunalinterchange
bdutipo_str Repositorios
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