Main pathways in the evolution of Antarctic fossil penguins (Seymour/Marambio Island, La Meseta Formation, Eocene): cooling events and marine circulation

The evolution of the Southern Ocean during the Paleogene played an important role in the origin of fossil penguins. Seymour/Marambio Island (La Meseta Formation, Eocene) contains one of the most complete records of the group in the world. The oldest undisputed record of penguins comes from the late...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Acosta Hospitaleche, Carolina Ileana Alicia, Reguero, Marcelo Alfredo
Formato: Objeto de conferencia Resumen
Lenguaje:Inglés
Publicado: 2010
Materias:
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/16623
Aporte de:
id I19-R120-10915-16623
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
Pinguinos
Evolución
spellingShingle Ciencias Naturales
Paleontología
Pinguinos
Evolución
Acosta Hospitaleche, Carolina Ileana Alicia
Reguero, Marcelo Alfredo
Main pathways in the evolution of Antarctic fossil penguins (Seymour/Marambio Island, La Meseta Formation, Eocene): cooling events and marine circulation
topic_facet Ciencias Naturales
Paleontología
Pinguinos
Evolución
description The evolution of the Southern Ocean during the Paleogene played an important role in the origin of fossil penguins. Seymour/Marambio Island (La Meseta Formation, Eocene) contains one of the most complete records of the group in the world. The oldest undisputed record of penguins comes from the late Paleocene. The lower levels of the La Meseta Formation (Ypresian, late early Eocene Acantilados Allomember, ~52-54 Ma) have recently yielded a low diversity penguin fauna (2 species) of a few specimens; the middle levels (Lutetian, Cucullaea I Allomember, middle Eocene, ~49 Ma) record a moderate diversity (8 species) whereas the highest levels (Priabonian, late Eocene, Submeseta Allomember, ~34-36 Ma) document a major taxonomic and body size diversity with 14 species cooccurring sympatrically. During the Paleogene climatic optimum the northern Antarctic Peninsula experienced a very warm, wet, non-seasonal climate, which persisted until early Eocene (~47 Ma). Temperatures thereafter became progressively cooler during a wet, strongly seasonal period in the mid middle Eocene that lasted until ~42 Ma. The distribution of living penguins is strongly linked to cool temperate waters, and the origin of this group was related to watercooling resulting from the evolution of circulation patterns in the Southern Ocean. Our data suggest that the highest diversity (14 species) and wider geographical distribution (Antarctica, South America and Australasia) in the late Eocene were linked to watercooling triggered by the opening of the Drake Passage and subsequent onset of the Antarctic Circumpolar Current.
format Objeto de conferencia
Resumen
author Acosta Hospitaleche, Carolina Ileana Alicia
Reguero, Marcelo Alfredo
author_facet Acosta Hospitaleche, Carolina Ileana Alicia
Reguero, Marcelo Alfredo
author_sort Acosta Hospitaleche, Carolina Ileana Alicia
title Main pathways in the evolution of Antarctic fossil penguins (Seymour/Marambio Island, La Meseta Formation, Eocene): cooling events and marine circulation
title_short Main pathways in the evolution of Antarctic fossil penguins (Seymour/Marambio Island, La Meseta Formation, Eocene): cooling events and marine circulation
title_full Main pathways in the evolution of Antarctic fossil penguins (Seymour/Marambio Island, La Meseta Formation, Eocene): cooling events and marine circulation
title_fullStr Main pathways in the evolution of Antarctic fossil penguins (Seymour/Marambio Island, La Meseta Formation, Eocene): cooling events and marine circulation
title_full_unstemmed Main pathways in the evolution of Antarctic fossil penguins (Seymour/Marambio Island, La Meseta Formation, Eocene): cooling events and marine circulation
title_sort main pathways in the evolution of antarctic fossil penguins (seymour/marambio island, la meseta formation, eocene): cooling events and marine circulation
publishDate 2010
url http://sedici.unlp.edu.ar/handle/10915/16623
work_keys_str_mv AT acostahospitalechecarolinaileanaalicia mainpathwaysintheevolutionofantarcticfossilpenguinsseymourmarambioislandlamesetaformationeocenecoolingeventsandmarinecirculation
AT regueromarceloalfredo mainpathwaysintheevolutionofantarcticfossilpenguinsseymourmarambioislandlamesetaformationeocenecoolingeventsandmarinecirculation
bdutipo_str Repositorios
_version_ 1764820463192637441