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Tertiary Research
The late Miocene mammalian fauna of Chorora, Awash basin, Ethiopia: systematics, biochronology and the^ 4^ 0K-^ 4^ 0Ar ages of the associated volcanics2002 •
2003 •
2022 •
The Early Pleistocene was a critical time period in the evolution of eastern African mammal faunas, but fossil assemblages sampling this interval are poorly known from Ethiopia’s Afar Depression. Field work by the Hadar Research Project in the Busidima Formation exposures (~2.7–0.8 Ma) of Hadar in the lower Awash Valley, resulted in the recovery of an early Homo maxilla (A.L. 666-1) with associated stone tools and fauna from the Maka’amitalu basin in the 1990s. These assemblages are dated to ~2.35 Ma by the Bouroukie Tuff 3 (BKT-3). Continued work by the Hadar Research Project over the last two decades has greatly expanded the faunal collection. Here, we provide a comprehensive account of the Maka’amitalu large mammals (Artiodactyla, Carnivora, Perissodactyla, Primates, and Proboscidea) and discuss their paleoecological and biochronological significance. The size of the Maka’amitalu assemblage is small compared to those from the Hadar Formation (3.45–2.95 Ma) and Ledi-Geraru (2.8–2....
Comptes Rendus de l'Académie des Sciences - Series IIA - Earth and Planetary Science
A new Middle Pleistocene fauna from the Busidima–Telalak region of the Afar, Ethiopia2000 •
2004 •
The terminal Pleistocene is a period of profound climatic and environmental change in Africa, with paleoenvironmental records documenting tremendous regional variation. Environmental records needed to understand these dynamics are currently lacking from the Horn of Africa. Here we provide a new paleoenvironmental record based of new faunal data from archeological sites along the Bulbula River (Ziway–Shala Basin, Main Ethiopian Rift) in Ethiopia. Research conducted in this area has uncovered archeological assemblages that document various phases of the Late Pleistocene and Early Holocene. Two sites dated to the terminal Pleistocene are considered here, B1s1 and B1s4. The former includes a very large assemblage of more than 20,000 skeletal remains. Both faunal assemblages are dominated by bovids of the tribes Alcelaphini and Antilopini and include Damaliscus hypsodon, a small extinct alcelaphine. The faunal remains from these sites, like those from the contemporary site of Lukenya Hill in south-central Kenya, are indicative of widespread arid grasslands. Several ungulates are found outside of their historic ranges, including Grant's gazelle (Nanger granti) and Dorcas gazelle (Gazella dorcas). Their absence from the region today likely reflects a combination of paleoenvironmental change since the end of the Pleistocene coupled with more recent human impacts. The combination of archeological and faunal data suggests that B1s1 could have been a residential site with seasonal occupation to acquire raw material from local obsidian sources and to hunt bovids in the arid plain, including species that ultimately disappear or shift their range at the onset of the Holocene with the return of warmer and moister conditions.
Anthropological Science
Preliminary geology and paleontology of new hominid-bearing Pliocene localities in the central Afar region of Ethiopia2007 •
Journal of Human Evolution
Evidence for a Late Pliocene faunal transition based on a new rodent assemblage from Oldowan locality Hadar A.L. 894, Afar Region, Ethiopia2012 •
The extensive outpouring of the Oligocene Trap basalts over eastern Africa and western Arabia was interrupted by a period of quiescence marked by the deposition of terrestrial sediments. These so-called intertrappean beds are often lignitiferous and yield recurrent floras and faunas, sometimes represented by endemic mammals. We intended to highlight the peculiar features of these sedimentary intercalations using a large-scale approach including eastern Africa and the western Arabian peninsula. Starting from a new mapping in the Eritrean highland, the intertrappean beds resulted a continuous level that was a few tens of meters thick and traceable for some tens of kilometers. They consist of fluvial red, green and gray mudstones and siltstones with subordinate channelized pebbly sandstones, and lignite seams. Two new 40Ar–39Ar datings constraint the age of the intertrappean beds between 29.0 Ma and 23.6 Ma. The outcrops near Mendefera have yielded the remains of two proboscidean families, the Deinotheriidae and the Gomphoteriidae. The morphological grade of the two Mendefera proboscideans would suggest a more derived stage than that of representatives of the same families from other Oligocene African sites (e.g., Chilga, Ethiopia). An Oligocene age could be inferred for them. The occurrence of the genus Prodeinotherium at Mai Gobro possibly represents the first occurrence of this taxon, while the Gomphotheirum sp. might represent the oldest occurrence of this taxon in Africa before its dispersal towards Asia and Europe. Proboscideans have also been found in the lowland intertrappean beds of Dogali near Massawa. These sediments were contiguous with the Eritrean highland intertrappean beds during the Oligocene, but are now tectonically displaced from them by two thousand meters of vertical topographical distance. Dogali is also known for the occurrence of possible Deinotheriidae remains and the primitive elephantoid Eritreum. Entering the Ethiopian highland, an inspection of the Agere Selam (Mekele) intertrappean beds revealed the occurrence of lacustrine limestones and diatomites, which were contrastingly quite subordinate with respect to the fine clastic sediments found in the nearby Amba Alaji area. Further south, the intertrappean section in the Jema valley (100 km north of Addis Ababa and close to the Blue Nile gorge) is 120 m thick with predominant clastic sediments and a few diatomite's at the top. Literature information from 35 additional sites, including northern Kenya, Yemen, Sudan and Saudi Arabia sections, confirms the fluvial and lacustrine depositional environment of the intertrappean beds, underlines the interest in their mammal fauna (Chilga, Losodok), and reports exploitable coal seams for some of them. As for the vegetal landscape in which the intertrappean beds were deposited, pollen and plant analysis results indicative of a tropical wet forest, similar to that of present-day western Africa. Another common feature of the intertrappean beds is their relatively limited thickness, averaging a few tens of meters, but reaching a few hundred meters in graben-related basins, such as Delbi Moye in southern Ethiopia. In most cases only thin, lens-shaped successions were deposited above the hummocky topography of their volcanic substratum, commonly unaffected by significant faulting. An average duration of the intertrappean beds is from one to three million years. This time interval is commonly matched by a few tens (or more rarely, hundreds) of meters of sediments left over after erosive episodes or depositional starvation. As to the lateral continuity of the intertrappean beds, the present-day outcrops show large differences: from some tens of kilometers in the Mendefera area, to a few tens of kilometres in the Jema valley, and to a few hundreds meters in the Agere Selam (Mekele) area. Even if it is difficult to quantify the original size of the sedimentation areas, it nevertheless proves that the intertrappean basins exceed thousands of square kilometers in only a single case (Mendefera), but were quite restricted in most cases. Their most likely endorheic and local character, together with a regional ill-defined fluvial network, was the effect of a water-course rerouting caused by the progressive rising of the eastern African and Arabian plateaux. Chronological constraints for the intertrappean beds can be inferred from the age of the hosting Trap succession and by the stratigraphical position that they occupy. Intervolcanic sedimentary episodes are typically found in the basaltic and subordinately rhyolitic successions that followed the 31–29 Ma old basaltic widespread paroxysm. With due caveats deriving from the discontinuous availability of datings specifically dedicated to this issue, we regard the age of the intertrappean beds as mostly encompassed in the interval from 29 to 27 Ma at the transition between the Early and Late Oligocene in the Ethiopia/Yemen Trap core. In marginal areas, such as SW Arabia, Eritrea and Kenya, the volcanic activity above the intertrappean beds resumed later, and its quiescence allowed a more prolonged period of sedimentation. The intertrappean beds fall in the second cooling event of the Oligocene climatic deterioration. During the contemporaneous apparent drop in the global sea-level and closure of the Tethyan Ocean between Arabia and southwestern Asia, connections were established between the African and the Eurasian continents. At that time, southwestern Asia was experiencing severe aridity with faunal exchanges toward the luxuriously vegetated eastern Africa.
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2008 •
2008 •
Rivista Italiana di …
The large fossil mammals from Buia (Eritrea): systematics, biochronology and paleoenvironments2004 •
1994 •
2012 •
2007 •
2022 •
Anthropological Science
Newly discovered Middle Pleistocene hominid-bearing deposits from the Lower Awash basin, Ethiopia2019 •
2005 •
Evolutionary Anthropology: Issues, News, and …
Fossil Mammals and Paleoenvironments in the Omo‐Turkana Basin2011 •
Journal of Human Evolution
Stratigraphic context and taxonomic assessment of the large cercopithecoid (Primates, Mammalia) from the late Early Pleistocene palaeoanthropological site of Buia (Eritrea)2010 •
Journal of Vertebrate Paleontology
Pliocene Bovidae (Mammalia) from the Hadar Formation of Hadar and Ledi-Geraru, Lower Awash, Ethiopia2012 •