Research Papers
Following are selected research papers co-authored by paleobotanist Bonnie Jacobs of the Environmental Science Program at Southern Methodist University on discoveries in Ethiopia of fauna believed to be 27-28 million years old.
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The Occurrence of the Fern Acrostichum in Oligocene
Volcanic Strata of the Northwestern Ethiopian Plateau
(International Journal of Plant Sciences - 2006)
Newly discovered, well-dated, Late Oligocene Acrostichum pinnae and associated trilete spores from the Chilga strata in northwestern Ethiopia allow us to describe more thoroughly the fossil species Acrostichum palaeoaureum and to explore its ecological role as a pioneer plant in response to disturbance by volcanic ash deposition in a wet climate.
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The fossil history of palms (Arecaceae)
in Africa and new records from the Late Oligocene
(28-27 million years ago) of northwestern Ethiopia
(Botanical Journal of the Linnean Society - 2006)
In this paper, we review the fossil record of African palms to document their evolution and extinction from the Late Cretaceous through the Cenozoic, and provide a framework into which additional fossil data can be incorporated.
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Oligocene Terrestrial Strata of Northwestern Ethiopia:
A Preliminary Report on Paleoenvironments and Paleontology
(Palaeontologia Electronica - May 2005)
The Paleogene record of Afro-Arabia is represented by few fossil localities, most of which are coastal. Here we report sedimentological and paleontological data from the continental Oligocene strata in northwestern Ethiopia. These have produced abundant plant fossils, thus filling a gap in what is known of Paleogene interior Afro-Arabia.
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Oligocene mammals from Ethiopia and
faunal exchange between Afro-Arabia and Eurasia
(Nature - 4 December 2003)
Afro-Arabian mammalian communities underwent a marked transition near the Oligocene/Miocene boundary at approximately 24 million years ago. Although it is well documented that the endemic paenungulate taxa were replaced by migrants from the Northern Hemisphere, the timing and evolutionary dynamics of this transition have long been a mystery because faunas from about 32 to 24 million years ago are largely unknown. Here we report a late Oligocene fossil assemblage from Ethiopia, which constrains the migration to postdate 27 million years ago, and yields new insight into the indigenous faunal dynamics that preceded this event.



