Gona is an archaeological site in the Afar Triangle of Ethiopia located within the Ethiopian Highlands.[1] The site is primarily known for paleoanthropological study near the Middle Awash and Hadar regions including excavations of Late Miocene–Early Pliocene fossils and Oldowan Industry stone tools. [2] Archaeological study of hominid fossils at the site is important to understanding human evolution processes while faunal remains give insight into early hominid diet and butchery practices. Evidence of human technology at Gona dates back to as early as 2.6 million years ago (mya) making Gona's stone tools the World's oldest stone artifacts found to date.[3]
Geography
editThe Ethiopian Highlands are split by the Rift Valley into two zones, which include the Afar and Middle Awash to the northeast and the Omo region to the southwest.[4] Gona and its archaeological sites are located in the area of the Afar Triangle of Ethiopia.[1] This positions Gona between the Mille-Bati road to the north, the Awash River to the east, the As Bole drainage to the south, and the Western Ethiopian escarpment that rises to the west.[5] Its core covers the drainage basin of the Kada Gona, a tributary of the Awash.[6] Geologically, the area is known for basalt and trachyte rock, which is regionally used to make stone tools.[4] Many of the area's archaeological sites are located near stream channels and riverbanks.[4]
Paleoenvironment
editPaleoanthropology
editHominid fossils from Gona are used by palaeoanthropologists studying human evolution in the Late Miocene–Early Pliocene, which is a time period sparsely preserved in the fossil record outside of key sites in Ethiopia, Kenya, and Chad.[7] Over 1,500 fossils were found during excavations at 40 sites in Gona between 1999 and 2003 with fossils from at least nine hominids recovered at the As Duma deposits without signs of transport from other areas.[7] These fossils from As Duma date to approximately 4.51 to 4.32 million years ago.[7]
Evidence from dentition including the morphology of molars, crowns, and roots alongside enamel thickness identify these hominids as Australopithecus ramidus.[7] Also present are fossils of early Homo including Homo erectus.[8] Evidence of Homo erectus was found at Gona's Busidima Formation with the excavation of a well-preserved pelvis.[9] This fossil had some obstetrical features similar to Australopithecus alongside derived features associated with Homo individuals such as a wider birth canal to accommodate encephalization and a larger head size at birth.[9]
Zooarchaeology
editThe bones, shells, and hides that animals leave behind after death are known as faunal remains, which are studied in the sub-discipline of zooarchaeology. These types of remains provide archaeological insight into the behavior and foodways of early hominids by preserving the types of food consumed as well as methods of preparation like butchery. Excavations in the Lower Busidima Formation at Gona show that food resources at the site included equids and bovids with cutmarked animal bones showing signs of butchery practices including skinning and filleting.[10] In addition to these mammal remains, the Adu-Asa Formation in Gona also contains some of the earliest anthropodal fossils.[11]
Cutmarked Bone
editArchaeological sites that preserve both faunal remains and stone tool assemblages are known as Type C sites and are important to studying the connection between meat consumption and stone tool manufacture.[10] The DAN2 (Dana Aoule) site at Gona is an example of a Type C assemblage including five cutmarked bones dated to approximately 2.1 Ma (millions of years).[10] Cutmarked specimens are important, because they can provide evidence of early hominid behavior in regards to food acquisition like hunting (arrowhead marks, etc.) and meat preparation techniques preserved by cutmarks left on animal bones during butchery. The cutmarked bones from DAN2 included a tibia midshaft fragment and four skeletal fragments that couldn't be definitively classified, but showed signs of filleting most commonly left on upper limb bones during experimental butchery studies.[10] While more data is needed to make definitive inferences about the acquisition of animal food sources study at Gona and neighboring sites like the Bouri Formation suggest that early stone tools were primarily used for butchery.[12] However, the existence of cutmarked bones at the site do suggest some level of hominids acquiring "fleshed carcasses" possibly through practices of hunting rather than scavenging.[10]
Stone Tools
editEvidence of human technology at the site dates back to as early as 2.6 million years ago (mya).[3] Basalt and trachyte rock are commonly used as local source material for the stone tools found at Gona alongside smaller percentages of 'exotic' stones like chert.[13] A majority of the tools found at Gona are from the Oldowan Industry, also known as Mode 1, and date to around 2.6-1.6 mya.[4] There is also evidence of the co-occurrence of Oldowan and Acheulean, or Mode 2, stone tools at Gona evidenced by an excavation that found artifacts from both of these industries nearby a Homo erectus cranial fossil.[14] These findings suggest an overlap of stone tool technology that challenges archaeological views of early Homo that attribute a single technology with a single species.[14] Additionally, the Oldowan artifacts at Gona dating to 2.6 mya form the oldest stone tool assemblages in the world and provide insight into early stone tool manufacture.[12] Stone tools from the site were first excavated from sedimentary deposits in the Hadar region of the Awash valley in 1976.[15] Radiometric dating and and magnetic polarity methods were used to determine the dates of these stone tool artifacts.[15]
Mary Leakey's stone tool typology organizes early stone assemblages into six categories: "Flaked Pieces (cores/choppers), Detached Pieces (flakes and fragments), Pounded Pieces (cobbles utilized as hammerstones), and Unmodified Pieces (manuports, stones transported to sites)."[12] Most stone tool assemblages are classified by these conventions. Artifact deposits at Gona include whole flakes, simple cores, and flaking debris including uniface and a few biface cores that are rarer at this site.[15] Practices of modified shaping by pounding and battering are preserved in artifacts like hammerstones and anvils.[15] Pitting and bruising found on the tools may be a result of pounding during the flaking process or arise from their use as hammerstones for activities like breaking bones to access marrow.[12] Unlike excavations at Olduvai, there is no current evidence of retouched flakes like stone scrapers at Gona.[15] Other important sites for stone tool assemblages in Ethiopia include Omo, Hadar, and Bouri as well as Lokalalei in Kenya.
References
edit- ^ a b Semaw, Sileshi; et al. (2003). "2.6-Million-year-old stone tools and associated bones fromOGS-6 and OGS-7, Gona, Afar, Ethiopia" (PDF). Journal of Human Evolution. 45 (2): 169–177. doi:10.1016/S0047-2484(03)00093-9. PMID 14529651. Archived (PDF) from the original on 22 May 2016.
- ^ "Smallest Homo erectus cranium in Africa and diverse stone tools found at Gona, Ethiopia". Michigan News. University of Michigan. 4 March 2020. Archived from the original on 7 May 2020.
- ^ a b Finneran, Niall (2007-11-08). The Archaeology of Ethiopia. Routledge. p. 36. ISBN 978-0-429-23647-1.
- ^ a b c d Finneran, Niall (2007-11-08). The Archaeology of Ethiopia. Routledge. p. 36. ISBN 978-0-429-23647-1.
- ^ Kleinsasser, Lynnette L.; et al. (2008). "Stratigraphy and geochronology of the late Miocene Adu-Asa Formation at Gona, Ethiopia". In Quade, Jay; Wynn, Jonathan G. (eds.). The Geology of Early Humans in the Horn of Africa. G.S.A. Special paper #446. Boulder, Colorado: Geological Society of America. pp. 33–65. doi:10.1130/2008.2446(02). ISBN 978-0-8137-2446-1. S2CID 130119615.
- ^ "Smallest Homo erectus cranium in Africa and diverse stone tools found at Gona, Ethiopia". Michigan News. University of Michigan. 4 March 2020. Archived from the original on 7 May 2020.
- ^ a b c d Semaw, Sileshi; Simpson, Scott W.; Quade, Jay; Renne, Paul R.; Butler, Robert F.; McIntosh, William C.; Levin, Naomi; Dominguez-Rodrigo, Manuel; Rogers, Michael J. (January 20, 2005). "Early Pliocene hominids from Gona, Ethiopia". Nature. 433 (7023): 301–305. doi:10.1038/nature03177. ISSN 0028-0836.
- ^ Simpson, S. W.; Quade, J.; Levin, N. E.; Butler, R.; Dupont-Nivet, G.; Everett, M.; Semaw, S. (2008-11-14). "A Female Homo erectus Pelvis from Gona, Ethiopia". Science. 322 (5904): 1089–1092. doi:10.1126/science.1163592. ISSN 0036-8075.
- ^ a b Simpson, S. W.; Quade, J.; Levin, N. E.; Butler, R.; Dupont-Nivet, G.; Everett, M.; Semaw, S. (2008-11-14). "A Female Homo erectus Pelvis from Gona, Ethiopia". Science. 322 (5904): 1089–1092. doi:10.1126/science.1163592. ISSN 0036-8075.
- ^ a b c d e DOMINGUEZ-RODRIGO, M; PICKERING, T; SEMAW, S; ROGERS, M (2005). "Cutmarked bones from Pliocene archaeological sites at Gona, Afar, Ethiopia: implications for the function of the world's oldest stone tools". Journal of Human Evolution. 48 (2): 109–121. doi:10.1016/j.jhevol.2004.09.004. ISSN 0047-2484.
- ^ Kleinsasser, Lynnette L.; et al. (2008). "Stratigraphy and geochronology of the late Miocene Adu-Asa Formation at Gona, Ethiopia". In Quade, Jay; Wynn, Jonathan G. (eds.). The Geology of Early Humans in the Horn of Africa. G.S.A. Special paper #446. Boulder, Colorado: Geological Society of America. pp. 33–65. doi:10.1130/2008.2446(02). ISBN 978-0-8137-2446-1. S2CID 130119615.
- ^ a b c d Semaw, Sileshi (2000). "The World's Oldest Stone Artefacts from Gona, Ethiopia: Their Implications for Understanding Stone Technology and Patterns of Human Evolution Between 2·6–1·5 Million Years Ago". Journal of Archaeological Science. 27 (12): 1197–1214. doi:10.1006/jasc.1999.0592. ISSN 0305-4403.
- ^ Finneran, Niall (2007-11-08). The Archaeology of Ethiopia. Routledge. pp. 36–38. ISBN 978-0-429-23647-1.
- ^ a b Semaw, Sileshi; Rogers, Michael J.; Simpson, Scott W.; Levin, Naomi E.; Quade, Jay; Dunbar, Nelia; McIntosh, William C.; Cáceres, Isabel; Stinchcomb, Gary E.; Holloway, Ralph L.; Brown, Francis H. (March 6, 2020). "Co-occurrence of Acheulian and Oldowan artifacts withHomo erectuscranial fossils from Gona, Afar, Ethiopia". Science Advances. 6 (10): eaaw4694. doi:10.1126/sciadv.aaw4694. ISSN 2375-2548.
- ^ a b c d e Semaw, Sileshi; et al. (January 23, 1997). "2 .5-million-year-old stone tools from Gona, Ethiopia". Nature. 385: 333–336.