Lukeino Formation | |
---|---|
Stratigraphic range: Late Miocene, Messinian, ~ [1] | |
Type | Geological formation |
Sub-units |
|
Underlies | Kaparaina Basalts and Toluk Beds |
Overlies | Kabarnet Trachyte and Mpesida Beds |
Lithology | |
Primary | Clay and loam [2] |
Other | Volcanic ash, carbonates and diatomites [2] |
Location | |
Region | Baringo County |
Country | Kenya |
Extent | Tugen Hills, Kenya |
The Lukeino Formation is a geologic formation located in Kenya and it dates to the Late Miocene (Messinian). [1]
The Lukeino Formation is believed to have been formed through continued tectonic plate activity, and it was located within a well-forested region [3] that was located nearby to Paleolake Lukeino. [2]
From 1971 to 1978, Martin Pickford had carried out extensive research in the Tugen Hills under a permit issued by the Kenyan Office of the President.
In 1974, Pickford found the first hominid fossil from the Lukeino Formation, a lower molar, which is included within the holotype of Orrorin tugenensis . [1] The rest of the holotype was found by Pickford and Brigitte Senut in 2000. [4]
Pierre & Pickford (2006) described eight hundred new micromammal fossils from the Kapsomin Member were described. [5]
Altner & Reichenbacher (2015) named the first fish from Paleolake Luekino: Kenyaichthys kipkechi . [6]
A P4 discovered at the Lukeino Formation has been proposed to belong to an amphicyonid by Morales et al. (2016), as both its age and dimensions are similar to Bonisicyon . [7]
Until the mid-1990s, only a few partial remains of cercopithecoideans were known from the Lukeino Formation, and then after surveys were conducted from 1998 onwards by the Kenya Palaeontology Expedition led to the discovery of new material within the Aragai Member, [8] a site situated in the lower levels of the Lukeino Formation. Most of the collection consists of craniodental specimens generally well-preserved in a hard matrix but there are three postcranial bones. As a result of this discovery, a new species was described by Kipkech et al. (2022): Sawecolobus lukeinoensis . [8]
Orrorin is an extinct genus of primate within Homininae from the Miocene Lukeino Formation and Pliocene Mabaget Formation, both of Kenya.
Sahelanthropus tchadensis is an extinct species of the hominid dated to about 7 million years ago, during the Miocene epoch. The species, and its genus Sahelanthropus, was announced in 2002, based mainly on a partial cranium, nicknamed Toumaï, discovered in northern Chad.
The Hominini form a taxonomic tribe of the subfamily Homininae ("hominines"). Hominini includes the extant genera Homo (humans) and Pan and in standard usage excludes the genus Gorilla (gorillas).
The Tugen Hills are a series of hills in Baringo County, Kenya. They are located in the central-western portion of Kenya.
Orthograde is a term derived from Greek ὀρθός, orthos + Latin gradi that describes a manner of walking which is upright, with the independent motion of limbs. Both New and Old World monkeys are primarily arboreal, and they have a tendency to walk with their limbs swinging in parallel to one another. This differs from the manner of walking demonstrated by the apes.
Proconsul major, an extinct primate of the genus Proconsul, was possibly the ancestor of Afropithecus and showed hominid characteristics. It occurred during the early Miocene and was roughly, the size of a gorilla. The species previously referred to as Ugandapithecus major is now considered to be a synonym of Proconsul major. Prior to 2000 it was known as Proconsul major and some argue against the renaming.
Pliohyrax, is a genus of hyracoids. It grew to sizes greatly exceeding those of any living hyrax, though it was by no means the largest member of this family.
The obturator externus groove is the groove on the posterior neck of the femur for the insertion of the obturator externus muscle, a muscle that is important during bipedal locomotion. It is located within the depression of the trochanteric fossa.
Martin Pickford is a lecturer in the Chair of Paleoanthropology and Prehistory at the Collège de France and honorary affiliate at the Département Histoire de la Terre in the Muséum national d'Histoire. In 2001, Martin Pickford together with Brigitte Senut and their team discovered Orrorin tugenensis, a hominid primate species dated between 5.8 and 6.2 million years ago and a potential ancestor of the genus Australopithecus.
Samburupithecus is an extinct primate that lived in Kenya during the middle to late Miocene. The one species in this genus, Samburupithecus kiptalami, is known only from a maxilla fragment dated to 9.5 million years ago discovered in 1982 and formally described by Ishida & Pickford 1997. The type specimen KNM-SH 8531 was discovered by the Joint Japan-Kenya Expedition at the SH22 fossil site in the Samburu District, a locality where several other researchers found no ape fossils.
Nacholapithecus kerioi was an ape that lived 14-15 million years ago during the Middle Miocene. Fossils have been found in the Nachola formation in northern Kenya. The only member of the genus Nacholapithecus, it is thought to be a key genus in early hominid evolution. Similar in body plan to Proconsul, it had a long vertebral column with six lumbar vertebrae, no tail, a narrow torso, large upper limbs with mobile shoulder joints, and long feet.
The Elisabeth Bay Formation, alternatively spelled as Elizabeth Bay Formation, is an Early Miocene geologic formation in the Sperrgebiet, ǁKaras Region of southwestern Namibia, overlying the Blaubok Conglomerate. The freshwater green and red siltstones, sandstones, intercalations of conglomerates and claystones of the formation were deposited in a fluvial environment, infilling a paleovalley incised during the Oligocene low sea stand, which backfilled during the Burdigalian marine transgression. The Elisabeth Bay Formation provides many fossil mammals, snakes and other reptiles.
The Black Crow Limestone is an Early Eocene geologic formation in the Sperrgebiet, ǁKaras Region of southwestern Namibia. The limestones of the approximately 10 metres (33 ft) thin formation were deposited in a lacustrine to paludal environment. The formation provides many fossil mammals and amphibians, reptiles, fresh water snails and fish.
Otavipithecus namibiensis is an extinct species of ape from the Miocene of Namibia. The fossils were discovered at the Berg Aukas mines in the foothills of the Otavi mountains, hence the generic name. The species was described in 1992 by Glenn Conroy and colleagues, and was at the time the only non-hominin fossil ape known from southern Africa. The scientists noted that the surrounding area of the discovered specimen included fauna dated at "about 13 ± 1 Myr". The fossils consist of part of the lower jawbone with molars, a partial frontal bone, a heavily damaged ulna, one vertebra and a partial finger bone.
The Ngorora Formation is a geological formation in Kenya preserving fossils dating to the Miocene. The uppermost member of the formation shows sign of a faunal turnover that occurred around 11 to 10.5 million years ago, coinciding with faunal changes elsewhere in the world. This turnover includes the arrival of the horse Hipparion in East Africa. The Ngorora Formation was initially mapped by G.R. Chapman in collaboration with the East African Geological Research Unit (EAGRU) and formally described by Bishop & Chapman in 1970. Major fossil finds were made in the early 1970s, with expeditions to the area recovering thousands of mammal, fish and mollusc remains alongside less common fossil material of birds and reptiles.
Brigitte Senut is a French paleoprimatologist and paleoanthropologist and a professor at the National Museum of Natural History, Paris. She is a specialist in the evolution of great apes and humans.
Asilifelis is an extinct genus of small felid that lived in what is now Kenya during the Early Miocene. Despite its fragmentary remains, it is remarkable because of its small size and advanced dentition. It contains a single species, Asilifelis cotae.
Namafelis is an extinct genus of felids that lived in what is now Namibia during the Early Miocene. It contains a single species, Namafelis minor. Closely related to Diamantofelis, it is of “Pseudaelurus-grade”, and therefore a rather basal member of the cat family.
Myacyon is an extinct genus of large sized carnivoran mammals, belonging to the family Amphicyonidae, that lived in Africa during the Miocene epoch. Due to the limited scope and fragmentary nature of the severely damaged holotype, as well as the illustrations in its descriptions, which have been called inadequate, usage of this genus poses serious issues. However, it is notable for being one of the last surviving members of its family and its adaptions to hypercarnivory. Its relationships to other amphicyonids are obscure, and it is not closely related to Bonisicyon, the other late surviving African genus, although it has been proposed that it descends from a species of Cynelos or Namibiocyon.
Namibiocyon is an extinct genus of carnivoran mammals, belonging to the family Amphicyonidae, that lived in Namibia during the Early Miocene epoch. Before the erection of this taxon in 2022, the type and only species, N. ginsburgi, had been assigned to a variety of other genera. It is notable for its adaptions toward hypercarnivory.