The Tugen Hills, often referred to as Saimo, are a group of hills in Kenya’s Baringo County. They are situated in Kenya’s central-western in Rift valley region. The Tugen Hills are one of the few places in Africa that still contain a series of deposits from between 14 and 4 million years ago, which makes them a crucial site for the study of human and animal evolution. A full skeleton of a 1.5 million-year-old elephant, a new species of primate, and the fossil remains of hominids who lived between 1 and 2 million years ago have all been discovered at the site of excavations by Richard Leakey and colleagues. Martin Pickford first visited the area in 1974 after discovering a single Orrorin tugenensis fossilised molar. The fossilised specimens were given the name Orrorin tugenensis, which translates to “Original Man of Tugen Hills,” in 1975. Between 6.2 MYA and 5.6 MYA, this hominid existed.
Brigitte Senut and Martin Pickford found fossilised remains of six-million-year-old humans here in 2000; the species was given the name Orrorin tugenensis in honour of the site. After Sahelanthropus tchadensis, this was the oldest hominid ever found in Kenya and the second-oldest in the entire world.
Given that the “Original Man of Tugen Hills” is thought to be the oldest hominid fossil ever discovered, this location is very important for understanding long-term environmental change. These deposits provide a window into the earth’s ecosystem as far back as 14 million years ago. For a comprehensive understanding of human evolution as well as the study of ancestor primates, the Tugen Hills are an essential site for archaeological excavation.
The Tugen Hills’ Miocene-era environment may be observed to have been shaped by volcanic materials and tectonic plate movement, which reveal the history of the East African Rift. It is notable that the Lukeino segments, where Orrorin was discovered, were generated by ongoing tectonic plate activity and basin formation. As was already established, the Tugen Hills include a variety of fossilised hominids, including the forerunners of modern humans, apes, and other primates. At this specific archaeological site, Orrorin tugenensis was specifically uncovered, and from this discovery, numerous theories about the progenitor cells of the human, chimpanzee, and orangutan were developed. In addition, “the Original man of Tugen Hills” has assisted anthropologists, archaeologists, and scientists in recognising the convergence and divergence between the hominid and the extinct ape.
The old world monkey in Tugen Hills
Old World monkeys have also been discovered, dug up, and studied in that location. Another 12.5 million year old fossil that has aided in understanding evolution and the ancestry of contemporary monkeys and apes is the early cercopithecoid monkeys of Kenya. The Pliocene and Pleistocene epochs’ fossil record can be used to analyse the Tugen Hills site in Kenya, despite the fact that much of the fossil record is poorly described. Which ranges in age from 12.5 Ma to 7.4 Ma, where there is a great deal of mystery about Old World Monkeys. The Tugen Hills can now be used as a site for evolutionary evidence and to study the middle to late Miocene epoch because of the examination and discoveries of the Cercopithecoids. Environmental conditions and those of earlier ancestral times. Tugen Hills contributes a lot of knowledge and discussion to our overall understanding of the earliest human progenitor. Martin Pickford and other paleoanthropologists emphasise the question of whether or not many of the fossil discoveries at Tugen Hills belong to humans or to apes and monkeys. As previously indicated, the Tugen Hills in Kenya are a crucial location for studying paleoanthropological studies and the transition from humans to contemporary apes.
Orrorin
Orrorin tugenensis, a hypothetical early Hominin species, was identified in 2000 and is thought to have existed between 6.1 and 5.7 million years ago. How Orrorin and current human beings are linked is unknown. Its finding was used to refute the theory that australopithecines are human ancestors, despite the fact that, as of 2012, this theory is still the most widely accepted explanation of human evolution.
The name of the species O. Tugenensis comes from the Tugen Hills in Kenya, where the first fossil was discovered in 2000, and the name of the genus Orrorin which in plural is Orroriek which means “original man” in Tugen. 20 fossils of the species have been discovered as of 2007.
- praegens, a second species, was recently added to the genus. This species, which originates from the Pliocene, is more recent than O. Tugenensis.
Description of fossils
It is thought that the 20 specimens discovered as of 2007 come from at least five different people. A symphysis and many isolated teeth are among them, together with two parts of the posterior mandible, three femur fragments, a half humerus, a proximal phalanx, and a distal thumb phalanx.
Considering the size of its body, Orrorin’s teeth were modest. Its dentition differs from that of Ardipithecus in that its enamel is thicker and its cheek teeth are thinner and less elongated mesiodistally than those found in Australopithecus. The presence of a mesial groove on the upper canines distinguishes the dentition from both of these species. The canines resemble those of female chimpanzees and Miocene apes but are smaller. In contrast to australopithecines, who were megadont and had large post-canines, orrorin was a microdont. Although the earliest members of the genus Homo, who were virtually probably the direct progenitors of today’s humans, were also megadonts, some experts disagree that this is convincing proof that Orrorin was more similar to human beings today than australopithecines.
The head and neck of the femur are oval in section, with the lesser trochanter protruding medially. The head is spherical and moved anteriorly. While these imply that Orrorin was a bipedal creature, the rest of its postcranium shows that it was a climber. The distal pollical phalanx, which is of human lengths and has been associated with tool-making despite the proximal phalanx’s curvature, should likely be relating with catching ability useful for climbing trees in this context.
The Kipsaraman village community museum housed the fossils after they were discovered in 2000, however the museum was later closed, it is believed that the fossils have now been hidden in a secure bank vault in Nairobi.
In 2017, reports observed impressions that resembled human footsteps on the Greek island of Crete. These “Trachilos footprints” were discovered in fossilised beach sands close to the settlement of Trachilos in west Creta and have been dated to the same time period as the Orrorin fossils, or 6.05 million years ago. There is disagreement about whether or not these prints are distinctive enough to categorically identify them as belonging to a primate, or even a vertebrate, or even whether they can even be classified as prints.
Australopithecines like Australopithecus afarensis (“Lucy”) may be viewed as a side branch of the hominid family tree if Orrorin is found to be a direct ancestor of today’s human beings, according to some paleoanthropologists. Orrorin is both older—by almost 3 million years—and more similar to modern humans than A. Afarensis. The biggest resemblance, while there is considerable disagreement on this point, is that the Orrorin femur is morphologically closer to that of Homo sapiens than is Lucy’s. The main point of contention in this discussion is that the Orrorin femur to which Lucy has been compared was a male, while Lucy was a female.
