Kenyanthropus

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Kenyanthropus
Cast of the skull of Kenyanthropus platyops

Cast of the skull of Kenyanthropus platyops

Temporal occurrence
Pliocene
3.5 to 3.3 million years
Locations
Systematics
Human (Hominoidea)
Apes (Hominidae)
Homininae
Hominini
Kenyanthropus
Scientific name
Kenyanthropus
Leakey et al., 2001
species
  • Kenyanthropus platyops

Kenyanthropus is an extinct species of primates from the family of apes , the immediate ancestor of their explorers people (the early Hominini has been assigned). Since Kenyanthropus sharessome traits with Paranthropus , Australopithecus anamensis and Homo rudolfensis , but deviates from these in others, its exact position inthe human family tree is controversial. Some researchers assume that Kenyanthropus is a special form of the genus Australopithecus .

Naming

Kenyanthropus is a made-up word . The name of the genus refers to the location of the first fossils assigned to the genus - a skull and an upper jaw - in Kenya ( English : Kenya) and is also derived from the Greek anthropus = man. The epithet of the only scientifically described species so far , Kenyanthropus platyops , refers to the external appearance of the reconstructed skull (Greek platus = flat, opsis = face). Kenyanthropus platyops therefore means “flat-faced person from Kenya”. In the English-speaking world, the skull is also called "Flat Faced Man".

Initial description

The holotype of the genus and also the type species Kenyanthropus platyops , a flattened skull with the archive number KNM-WT 40000 and broken into numerous small fragments, was discovered in August 1999 by Justus Erus west of Lake Turkana on the so-called Lomekwi locality , which is located in the Northern Kenya drained towards Lake Turkana, discovered. In the first description, the largely complete skull was placed alongside the fragment of a left upper jaw as a paratype (KNM-WT 38350), which had already been recovered from Blasto Onyango in August 1998 at the same location. The fossil KNM-WT 40000 was dated to an age of 3.5 million years and is kept in Nairobi in the headquarters of the National Museums of Kenya (formerly: Kenya National Museum , hence KNM).

According to the first description, the size of the only skull of Kenyanthropus discovered so far corresponds to that of Australopithecus africanus and Australopithecus afarensis , but the shape of the facial skull was reconstructed from hundreds of fragments much flatter than that of the two Australopithecus species. The cheekbones are large and the roof of the mouth is wide, the nostril is rather narrow and the ear canal is narrow. Few teeth have survived, but one molar is unusually small and the enamel is thick. The brain volume is difficult to determine due to the deformations. It is also interesting that Australopithecus afarensis lived in Africa at the same time as Kenyanthropus platyops . The habitat of Kenyanthropus could be identified as relatively moist and therefore well overgrown on the basis of accompanying botanical and zoological finds . The numerous finds of fossil hornbeams suggest a landscape that was characterized by transitions between savannah and bush landscapes and in which there were also watercourses and lakes with gallery forests .

The locomotion of the individuals of Kenyanthropus is unclear, as no arm or leg bones have been discovered.

controversy

Both finds, on which the first description of Kenyanthropus was based, were found in the worst possible condition: the skull KNM-WT 40000 had been crushed into more than a thousand scraped fragments, and the upper jaw KNM-WT 38350 also consisted of several fragments. Several dozen other finds, including a right lower jaw with all molar teeth (KNM-WT 8556), a skull fragment with an auditory canal (KNM-WT 4001) and various teeth, come from found layers similar to those of the two fragments of the type specimen but no features by which they could be clearly assigned to Kenyanthropus . In 2003, Tim White argued that the skull fragments were far too badly deformed ("these characters have virtually all been influenced to varying degrees by expanding matrix distortion") for their reconstruction to be the basis for a new generic name; it is possibly a variant of Australopithecus afarensis . Other scientists questioned the findings in the near Australopithecus anamensis or suggested him as Homo platyops to Homo to ask. Meave Leakey, however, stuck to her thesis of an independent genre.

Occasionally the species Homo rudolfensis is interpreted as another species of the genus Kenyanthropus and then referred to as "Kenyanthropus rudolfensis".

Stone appliance

In the immediate vicinity of the site of Kenyanthropus platyops , stone tools of the Oldowan type and remains from the manufacture of such tools were found from 2011 . While most of the tools were discovered on the surface, 19 objects with an artefact character that can not be unequivocally clarified come from deeper sediment layers and can therefore be geologically dated. Their age is 3.3 million years , according to a study published in Nature . If this dating is correct, it would be the oldest stone tools known to date and come from an era from which no fossils of the genus Homo are known; the oldest evidence for the genus Homo is the fossil LD 350-1 , which was dated to an age of 2.8 to 2.75 million years. Sonia Harmand of Stony Brook University , under whose direction the artifacts were recovered and dated, named them after the location as evidence of the archaeological culture of Lomekwian .

literature

  • Karen E. Lange: Meet Kenya Man. In: National Geographic , October 2001, pp. 84–88 (with numerous illustrations, including the fragments that have not yet been reconstructed)

See also

Web links

Commons : Kenyanthropus platyops  - Collection of images, videos and audio files

Individual evidence

  1. ^ Meave G. Leakey , Fred Spoor, Frank H. Brown et al .: New hominin genus from eastern Africa shows diverse middle Pliocene lineages. In: Nature . Volume 410, 2001, pp. 433-440, doi: 10.1038 / 35068500 .
  2. ↑ Roberts, Alice .: The Beginnings of Mankind. From the upright gait to the early high cultures . Dorling Kindersley, Munich 2012, ISBN 978-3-8310-2223-6 .
  3. ↑ Tim White: Early Hominids - Diversity or Distortion? In: Science . Volume 299, 2003, pp. 1994-1997, doi: 10.1126 / science.1078294
  4. ^ Camilo J. Cela-Conde, Francisco J. Ayala: Genera of the human lineage. In: PNAS , Volume 100, 2003, pp. 7684-7689, doi: 10.1073 / pnas.0832372100
  5. ↑ Stone-knocking flat faces FAZ v. May 27, 2015 (accessed May 27, 2015)
  6. ↑ Sonia Harmand et al .: 3.3-million-year-old stone tools from Lomekwi 3, West Turkana, Kenya. In: Nature. Volume 521, 2015, pp. 310-315, doi: 10.1038 / nature14464
  7. ↑ Criticism of the reliability of the dating was expressed by Tim White , among others , see Stones are still missing for this theory. In: Frankfurter Allgemeine Zeitung. No. 116 of May 21, 2015, p. 9
  8. ↑ Scientists discover world's oldest stone tools. On: eurekalert.org from May 20, 2015
  9. ↑ World's oldest stone tools discovered in Kenya. On: sciencemag.org April 14, 2015.
  10. ↑ Ewen Callaway: Oldest stone tools raise questions about their creators. In: Nature. Volume 520, No. 7548, 2015, p. 421, doi: 10.1038 / 520421a , full text .