Olduvai Gorge
Encyclopedia
The Olduvai Gorge is a steep-sided ravine
in the Great Rift Valley
that stretches through eastern Africa. It is in the eastern Serengeti Plains
in northern Tanzania
and is about 48 km (29.8 mi) long. It is located 45 km from the Laetoli
archaeological site. The gorge is an important prehistoric site, sometimes called "the Cradle of Mankind."
The name is a misspelling of Oldupai Gorge, which was adopted as the official name in 2005. Oldupai is the Maasai
word for the wild sisal plant Sansevieria ehrenbergii
, which grows in the gorge.
.
Virginia Morell (Ancestral Passions: The Leakey Family and the Quest for Humankind's Beginnings, 1995, Simon & Schuster, p. 57) treats this "tumbling story" as a tale. She writes: "Louis [Leakey] liked to depict Kattwinkel" as a nearsighted butterfly collector" who tumbled down. . . . He may not have lost his footing at the edge of the gorge [in 1911], but he did explore its eroded slopes and brought back a small collection of fossils."
Excavation work there was pioneered by Louis
and Mary Leakey
beginning in 1931 and continued into the 21st century by Professor Fidelis Masao of the Open University
of Tanzania supported by Earthwatch; there have also been teams from Rutgers University
. Millions of years ago, the site was that of a large lake, the shores of which were covered with successive deposits of volcanic ash
. Around 500,000 years ago seismic activity
diverted a nearby stream which began to cut down
into the sediment
s, revealing seven main layers
in the walls of the gorge. The geology of Olduvai Gorge and the surrounding region was studied in detail by Richard L. Hay, who worked at the site between 1961 and 2002.
The stratigraphy
is extremely deep and layers of volcanic ash and stones allow radiometric dating
of the embedded artifacts, mostly through potassium-argon dating
and Argon–argon dating. The base of the Olduvai sediments dates to slightly older than 2 million years, with the first artifacts
(pebble tools and choppers
) appearing slightly above. Nearby site Laetoli
has a much older fossil record
.
The earliest archaeological deposit, known as Bed I, has produced evidence of campsites and living floors along with stone tool
s made of flakes
from local basalt
and quartz
. Since this is the site where these kinds of tools were first discovered, these tools are called Oldowan. It is now thought that the Oldowan toolmaking tradition started about 2.6 million years ago. Bones from this layer are not of modern humans but primitive hominid
forms of Paranthropus boisei
and the first discovered specimens of Homo habilis
.
The site of Frida Leakey Korongo North (commonly known as FLK North and named after Louis Leakey's first wife) bears the distinction of having the oldest known evidence of Elephant
consumption, attributed to Homo ergaster
around 1.8 million years ago
. A nearly complete skeleton of the extinct Elephas recki
was found in the lowest of its six occupation levels along with stone tools such as choppers and flakes
. Large numbers of bone fragments of smaller animals found with it clearly identify FLK North as an early butchering site.
Above this, in Bed II, pebble tools begin to be replaced by more sophisticated handaxes of the Acheulean
industry
and made by H. ergaster. This layer has not yet been successfully dated, but likely falls between 1.75 and 1.2 million years.
Beds III and IV have produced Acheulean
tools and fossil bones from more than 600,000 years ago.
During a period of major faulting and volcanism
roughly 400,000 to 600,000 years ago, the Masek Beds were made.
Beds above these contained tools from a Kenya-Capsian industry made by modern humans and are termed the Masek Beds (600,000 to 400,000 years ago), the Ndutu Beds (400,000 to 32,000 years ago), and the Naisiusiu Beds (22,000 to 15,000 years ago).
Also located on the rim of the Gorge is the Olduvai Gorge Museum
. This Museum presents exhibitions pertaining to the Gorge's history.
Ravine
A ravine is a landform narrower than a canyon and is often the product of streamcutting erosion. Ravines are typically classified as larger in scale than gullies, although smaller than valleys. A ravine is generally a fluvial slope landform of relatively steep sides, on the order of twenty to...
in the Great Rift Valley
Great Rift Valley
The Great Rift Valley is a name given in the late 19th century by British explorer John Walter Gregory to the continuous geographic trench, approximately in length, that runs from northern Syria in Southwest Asia to central Mozambique in South East Africa...
that stretches through eastern Africa. It is in the eastern Serengeti Plains
Serengeti
The Serengeti ecosystem is a geographical region in Africa. It is located in north Tanzania and extends to south-western Kenya between latitudes 1 and 3 S and longitudes 34 and 36 E. It spans some ....
in northern Tanzania
Tanzania
The United Republic of Tanzania is a country in East Africa bordered by Kenya and Uganda to the north, Rwanda, Burundi, and the Democratic Republic of the Congo to the west, and Zambia, Malawi, and Mozambique to the south. The country's eastern borders lie on the Indian Ocean.Tanzania is a state...
and is about 48 km (29.8 mi) long. It is located 45 km from the Laetoli
Laetoli
Laetoli is a site in Tanzania, dated to the Plio-Pleistocene and famous for its hominin footprints, preserved in volcanic ash . The site of the Laetoli footprints is located 45 km south of Olduvai gorge.-Date:...
archaeological site. The gorge is an important prehistoric site, sometimes called "the Cradle of Mankind."
The name is a misspelling of Oldupai Gorge, which was adopted as the official name in 2005. Oldupai is the Maasai
Maasai language
The Maasai language is an Eastern Nilotic language spoken in Southern Kenya and Northern Tanzania by the Maasai people, numbering about 800,000...
word for the wild sisal plant Sansevieria ehrenbergii
Sansevieria ehrenbergii
Sansevieria ehrenbergii is a flowering plant which grows in northeastern Africa from Libya south to Tanzania,Oman and also in Saudi Arabia. It occurs notably in proliferation along the Olduvai Gorge in northern Tanzania...
, which grows in the gorge.
Geology and paleontology
Olduvai Gorge is one of the most important prehistoric sites in the world and has been instrumental in furthering understanding of early human evolutionHuman evolution
Human evolution refers to the evolutionary history of the genus Homo, including the emergence of Homo sapiens as a distinct species and as a unique category of hominids and mammals...
.
Chasing a fancy butterfly in the green wilds of TanganyikaTanganyikaTanganyika , later formally the Republic of Tanganyika, was a sovereign state in East Africa from 1961 to 1964. It was situated between the Indian Ocean and the African Great Lakes of Lake Victoria, Lake Malawi and Lake Tanganyika...
50 years ago, a German entomologist named (Wilhelm) Kattwinkel tumbled off a rocky ledge and nearly killed himself. When he regained his senses, he found himself in an anthropologist's dream world: an erosion-created rift with layer after layer of fossils, bones and ancient artifacts. The find was named Olduvai Gorge, and Kattwinkel's heirs ever since have been scrambling up and down its sun-baked sides in search of clues to man's earliest awakening. (Time, 10 March 1961)
Virginia Morell (Ancestral Passions: The Leakey Family and the Quest for Humankind's Beginnings, 1995, Simon & Schuster, p. 57) treats this "tumbling story" as a tale. She writes: "Louis [Leakey] liked to depict Kattwinkel" as a nearsighted butterfly collector" who tumbled down. . . . He may not have lost his footing at the edge of the gorge [in 1911], but he did explore its eroded slopes and brought back a small collection of fossils."
Excavation work there was pioneered by Louis
Louis Leakey
Louis Seymour Bazett Leakey was a British archaeologist and naturalist whose work was important in establishing human evolutionary development in Africa. He also played a major role in creating organizations for future research in Africa and for protecting wildlife there...
and Mary Leakey
Mary Leakey
Mary Leakey was a British archaeologist and anthropologist, who discovered the first skull of a fossil ape on Rusinga Island and also a noted robust Australopithecine called Zinjanthropus at Olduvai. For much of her career she worked together with her husband, Louis Leakey, in Olduvai Gorge,...
beginning in 1931 and continued into the 21st century by Professor Fidelis Masao of the Open University
Open University
The Open University is a distance learning and research university founded by Royal Charter in the United Kingdom...
of Tanzania supported by Earthwatch; there have also been teams from Rutgers University
Rutgers University
Rutgers, The State University of New Jersey , is the largest institution for higher education in New Jersey, United States. It was originally chartered as Queen's College in 1766. It is the eighth-oldest college in the United States and one of the nine Colonial colleges founded before the American...
. Millions of years ago, the site was that of a large lake, the shores of which were covered with successive deposits of volcanic ash
Volcanic ash
Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact...
. Around 500,000 years ago seismic activity
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
diverted a nearby stream which began to cut down
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...
into the sediment
Sediment
Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....
s, revealing seven main layers
Stratum
In geology and related fields, a stratum is a layer of sedimentary rock or soil with internally consistent characteristics that distinguish it from other layers...
in the walls of the gorge. The geology of Olduvai Gorge and the surrounding region was studied in detail by Richard L. Hay, who worked at the site between 1961 and 2002.
The stratigraphy
Stratigraphy
Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary and layered volcanic rocks....
is extremely deep and layers of volcanic ash and stones allow radiometric dating
Radiometric dating
Radiometric dating is a technique used to date materials such as rocks, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates...
of the embedded artifacts, mostly through potassium-argon dating
Potassium-argon dating
Potassium–argon dating or K–Ar dating is a radiometric dating method used in geochronology and archeology. It is based on measurement of the product of the radioactive decay of an isotope of potassium into argon . Potassium is a common element found in many materials, such as micas, clay minerals,...
and Argon–argon dating. The base of the Olduvai sediments dates to slightly older than 2 million years, with the first artifacts
Artifact (archaeology)
An artifact or artefact is "something made or given shape by man, such as a tool or a work of art, esp an object of archaeological interest"...
(pebble tools and choppers
Hand axe
A hand axe is a bifacial Stone tool typical of the lower and middle Palaeolithic , and is the longest-used tool of human history.-Distribution:...
) appearing slightly above. Nearby site Laetoli
Laetoli
Laetoli is a site in Tanzania, dated to the Plio-Pleistocene and famous for its hominin footprints, preserved in volcanic ash . The site of the Laetoli footprints is located 45 km south of Olduvai gorge.-Date:...
has a much older fossil record
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
.
The earliest archaeological deposit, known as Bed I, has produced evidence of campsites and living floors along with stone tool
Stone tool
A stone tool is, in the most general sense, any tool made either partially or entirely out of stone. Although stone tool-dependent societies and cultures still exist today, most stone tools are associated with prehistoric, particularly Stone Age cultures that have become extinct...
s made of flakes
Lithic flake
In archaeology, a lithic flake is a "portion of rock removed from an objective piece by percussion or pressure," and may also be referred to as a chip or spall, or collectively as debitage. The objective piece, or the rock being reduced by the removal of flakes, is known as a core. Once the proper...
from local basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
and quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...
. Since this is the site where these kinds of tools were first discovered, these tools are called Oldowan. It is now thought that the Oldowan toolmaking tradition started about 2.6 million years ago. Bones from this layer are not of modern humans but primitive hominid
Hominidae
The Hominidae or include them .), as the term is used here, form a taxonomic family, including four extant genera: chimpanzees , gorillas , humans , and orangutans ....
forms of Paranthropus boisei
Paranthropus boisei
Paranthropus boisei was an early hominin and described as the largest of the Paranthropus species...
and the first discovered specimens of Homo habilis
Homo habilis
Homo habilis is a species of the genus Homo, which lived from approximately at the beginning of the Pleistocene period. The discovery and description of this species is credited to both Mary and Louis Leakey, who found fossils in Tanzania, East Africa, between 1962 and 1964. Homo habilis Homo...
.
The site of Frida Leakey Korongo North (commonly known as FLK North and named after Louis Leakey's first wife) bears the distinction of having the oldest known evidence of Elephant
Elephant
Elephants are large land mammals in two extant genera of the family Elephantidae: Elephas and Loxodonta, with the third genus Mammuthus extinct...
consumption, attributed to Homo ergaster
Homo ergaster
Homo ergaster is an extinct chronospecies of Homo that lived in eastern and southern Africa during the early Pleistocene, about 2.5–1.7 million years ago.There is still disagreement on the subject of the classification, ancestry, and progeny of H...
around 1.8 million years ago
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
. A nearly complete skeleton of the extinct Elephas recki
Elephas recki
Elephas recki is an extinct species related to the Asian elephant Elephas maximus. At up to 15 feet in shoulder height, it was one of the largest elephant species to have ever lived. It is believed that E. recki ranged throughout Africa between 3.5 and 1 million years ago. The Asian Elephant is...
was found in the lowest of its six occupation levels along with stone tools such as choppers and flakes
Lithic flake
In archaeology, a lithic flake is a "portion of rock removed from an objective piece by percussion or pressure," and may also be referred to as a chip or spall, or collectively as debitage. The objective piece, or the rock being reduced by the removal of flakes, is known as a core. Once the proper...
. Large numbers of bone fragments of smaller animals found with it clearly identify FLK North as an early butchering site.
Above this, in Bed II, pebble tools begin to be replaced by more sophisticated handaxes of the Acheulean
Acheulean
Acheulean is the name given to an archaeological industry of stone tool manufacture associated with early humans during the Lower Palaeolithic era across Africa and much of West Asia, South Asia and Europe. Acheulean tools are typically found with Homo erectus remains...
industry
Archaeological industry
An archaeological industry, normally just "industry", is the name given in the study of prehistory to a consistent range of assemblages connected with a single product, such as the Langdale axe industry...
and made by H. ergaster. This layer has not yet been successfully dated, but likely falls between 1.75 and 1.2 million years.
Beds III and IV have produced Acheulean
Acheulean
Acheulean is the name given to an archaeological industry of stone tool manufacture associated with early humans during the Lower Palaeolithic era across Africa and much of West Asia, South Asia and Europe. Acheulean tools are typically found with Homo erectus remains...
tools and fossil bones from more than 600,000 years ago.
During a period of major faulting and volcanism
Volcanism
Volcanism is the phenomenon connected with volcanoes and volcanic activity. It includes all phenomena resulting from and causing magma within the crust or mantle of a planet to rise through the crust and form volcanic rocks on the surface....
roughly 400,000 to 600,000 years ago, the Masek Beds were made.
Beds above these contained tools from a Kenya-Capsian industry made by modern humans and are termed the Masek Beds (600,000 to 400,000 years ago), the Ndutu Beds (400,000 to 32,000 years ago), and the Naisiusiu Beds (22,000 to 15,000 years ago).
Also located on the rim of the Gorge is the Olduvai Gorge Museum
Olduvai Gorge Museum
The Olduvai Gorge Museum is located in the Ngorongoro Conservation Area in Northern Tanzania on the edge the of Olduvai Gorge. The museum was founded by Mary Leakey and is now under the jurisdiction of the Tanzanian government's Department of Cultural Antiquities...
. This Museum presents exhibitions pertaining to the Gorge's history.
See also
- Geography of TanzaniaGeography of TanzaniaTanzania's geography is one of the most varied and unique in the world; it contains Africa's highest point, Mount Kilimanjaro , as well as lakes, mountains and many natural parks....
- List of fossil sites
- Olduvai imperativeOlduvai imperativeThe Olduvai imperative is the human desire or need to create tools. It is named after the Olduvai Gorge in northern Tanzania where prehistoric tools were found.- References :*http://www.ablibris.com/site/review.php3?bid=1066...
- Olduvai theoryOlduvai theoryThe Olduvai theory states that industrial civilization will have a lifetime of less than or equal to 100 years . The theory provides a quantitative basis of the transient-pulse theory of modern civilization...