The origins of humans are thought to be mostly in Africa, where the earliest evidence of hominids has been found by various scientists. The discovery of fossils in various areas of the African continent has also shed light on human evolution and culture. This paper explains how the discoveries at Fayson, Rusinga Island, Laetoli, and Tugen Hills support the role of the African fossil record in the evolution of hominids. At Fayson, a team of international scientists unearthed bones, teeth, and skull they claimed to belong to three Homo Sapiens adults, a child, and a teenager among stone tools and animal bones (Haeuster & McHenry, 2007). The dating of the discovered tools indicated that the three Homo Sapiens adults, the child, and the teenager were between 281,000 and 349,000 years old (Haeuster & McHenry, 2007). The Fayson discovery by a team of scientists created a significant boost to the scarce record of fossil for early Homo sapiens (Haeuster & McHenry, 2007).
Additionally, before the fossil discovery at Fayson, the oldest known Homo sapiens around the area were 195,000-year-old remains found in Ethiopia at a place called Omo Kibish (Haeuster & McHenry, 2007). According to the scientists, the discovery at the Moroccan Fayson was the strongest evidence of Homo sapiens in that part of Africa (Haeuster & McHenry, 2007). The discovery indicated that as Homo sapiens started emerging from its ancestral species, it rapidly spread over the entire African continent (Haeuster & McHenry, 2007). Besides, while little is known about how the discovered group lived, the wildebeest, gazelle bones, and other remains of large mammals at the discovery site showed that the discovered early humans were primarily game hunters (Haeuster & McHenry, 2007).
The findings from Rusinga Island
Rusinga Island is broadly recognized for its extremely important and rich fossil beds of the extinct Miocene mammals, which scientists date back to eighteen million years (Van Couvering & Miller, 1969). The Island had only been explored superficially until the years 1947 to 1948 when Louis Leakey commenced systematic excavations and searches, which have intermittently continued since then (Van Couvering & Miller, 1969). The year 1948 ended with the collection of approximately 15,000 fossils from the Miocene, which included sixty-four primates identified by Leakey as “Miocene apes” (Van Couvering & Miller, 1969).
All the Proconsul species were part of the 64 primates, and Leakey collectively named them Africanus, although most of them later got reclassified into heseloni and nyanzae major (Van Couvering & Miller, 1969). The first complete Proconsul skull, which was considered as a “stem hominoid,” was discovered by Mary Leakey in the year 1948. The excavation of fossils in Rusinga Island was completed in 1993 by Louis Leakey’s native assistant, Heselon Mukiri (Van Couvering & Miller, 1969). As a result of Louis Leakey’s discoveries, several thousands of fossils are today recognized from five major sites within the Island, with plentiful of hominoids including Nyanzapithecus, Dendropithecus, Limnopithecus, Micropithecus, and almost a complete skeleton of Proconsul’s second species. They all exhibit arboreal as opposed to terrestrial adaptations (Van Couvering & Miller, 1969).
Since the first true monkeys did not exist until about 15 million years ago, it is believed that the different Early Miocene African catarrhines, such as those discovered in Rusinga Island, completed that adaptive niche (Van Couvering & Miller, 1969). However, the phylogenetic position of the primates found on Rusinga Island had been broadly debated, with other scientists theorizing that Proconsul is a stem catarrhine. The scientists, therefore, claimed that Proconsul is ancestral to both the old-world monkeys (Cercopithecids) and the great apes and humans (hominids), as opposed to a stem hominoid (Van Couvering & Miller, 1969). Also, different Pleistocene mammal fossils, such as Rusingoryx (extinct antelope), were predominant in the ancient shoreline deposits in Rusinga Island, and they were left behind as the level of water in Lake Victoria slowly reduced over the centuries (Van Couvering & Miller, 1969).
The Findings from Laetoli
Laetoli is a Tanzania archeological site dated back to the Plio-Pleistocene and known for the discovery of hominin footprints, which got preserved in volcanic ash (White, 1980). The Laetoli footprints site lies 45 kilometers in the southern part of Olduvai gorge, and the footprints got discovered in the year 1976 by Mary Leakey, and later excavated in 1978 (White, 1980). According to the analysis of the impressions of the footfall, the Laetoli Footprints indicated convincing evidence for the bipedalism theory in Pliocene hominins, which gave it high recognition by both the public and scientists (White, 1980). As a result, paleontological expeditions have been conducted since the year 1998. Such expeditions led to the discovery of several new findings of hominin, as well as an extensive paleoecology reconstruction (White, 1980).
Dating back to 3.7 million years, the Laetoli footprints form the oldest known hominin bipedalism evidence at that time. However, older Ardipithecus ramidus fossils were later discovered with various features, which gave indications of bipedalism (White, 1980). Due to the discovery of the footprints, several other discoveries got excavated at the Laetoli site, including remains of animal skeletons and hominin (White, 1980). The evaluation of the skeletal structure and footprints gave a clear suggestion that bipedalism emerged in hominins before enlarged brains. However, it is not easy to identify the hominins at a species level, although the most commonly proposed species to have made the trace is Australopithecus afarensis (White, 1980).
The findings from Tugen hills
The Tugen hills lie in the Kenyan Baringo County in the central-western part of Kenya. The Tugen Hills form part of the few locations in Africa that preserve a series of fossil deposits from the time of between fourteen to four years ago, which makes them important areas for the study of the evolution of humans and animals (Pickford & Kunimatsu, 2005). The excavations conducted at Tugen Hills by Richard Leakey in the year 1967 resulted in the discovery of fossil remains of 1 to 2 million-year-old hominids, new species of monkeys, and a complete skeleton of approximately 1.5-million-year-old-elephant (Pickford & Kunimatsu, 2005).
Additionally, at the same site, Martin Pickford and Brigitte Senut discovered six-million-year-old hominid fossils in the year 2000 and named the species as “Orrorin tugenensis,” which stood as the oldest hominid ever found in Kenya and the world’s second oldest hominid after Sahelanthropus tchadensis (Pickford & Kunimatsu, 2005). The discovery of hominid in Tugen Hills was majorly based on the thigh of the species, which has various telltale features relating to upright walking (Pickford & Kunimatsu, 2005). The analysis conducted later in the year 2008 confirmed that the species was capable of walking upright, meaning Orrorin in the local language.
The findings from Fayson, Rusinga Island, Laetoli, and Tugen hills provide significant proof of the importance of African fossil record in defining the development of hominids. The discoveries of fossils in Fayson, Rusinga Island, Laetoli, and Tugen hills indicate a clear evidence of early transitional hominins, which lived after the divergence from the common hominid ancestor during the early Pliocene Epochs and the late Miocene periods.
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