Iwo-eleru skull

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Map of Nigeria with location (bottom left)
Views of the Iwo Eleru skull (top left): from the side, from the front, from above, from below

The Iwo Eleru skull is an archaeological find that was unearthed in an excavation site known as Iwo Eleru . The site is a large cave - an abri - in the southwest of Nigeria , in the state of Ondo , 24 km northwest of Akure . Excavations took place there from 1965 onwards, in the course of which tens of thousands of artifacts from the late Later Stone Age were recovered. The most important find was the skull of an adult human ( Homo sapiens ), probably that of a man. In a study published in 1971, the Iwo-Eleru skull was dated to an age of almost 10,000 years on the basis of charcoal residues that were in the same find horizon . In 2010 this dating was corrected and now shown as 11,200 ± 200 years. The dead man was deposited in the cave in the gap between two boulders and covered with a thin layer of earth. Over the millennia, the bones of the body beneath its skull had largely been destroyed and therefore no longer suitable for a precise analysis. More recent traces of settlement in the cave reached into the epoch around 3500 years before today.

features

The roof of the skull and the lower jaw could be reconstructed from the fragments obtained. There are only a few fragments of the upper jaw. The preserved teeth are no longer in the bandage of the jaw. Already in the first description from 1971 and in connection with a study published by Chris Stringer in 1974 it was shown that the skull exhibits an unusual combination of features of the archaic Homo sapiens and the anatomically modern human being. Remember in particular the profile of the face and the construction of the skull to the more than 100,000-year-old skull Omo 2 from Ethiopia and as Homo soloensis become known Homo erectus - finds from Java , and also let him be mandible robust striking. Therefore, the find cannot be assigned to any of the contemporary African populations.

In 2011 this interpretation was confirmed in principle, but the dating of the skull was revised again: With the help of uranium-thorium dating , a period of 16,300 ± 500 to 11,700 ± 1,700 years ago was calculated for the age. A comprehensive comparison with other - recent as well as archaic - human skulls showed that the Iwo Eleru skull has an "intermediate shape between archaic hominins ( Neanderthals and Homo erectus ) and modern humans". The features of the skull are therefore outside the range for the variability of today's living populations of anatomically modern humans and most closely resemble the 100,000-year-old skull finds by Skhul and Qafzeh .

Interpretation of the characteristics

The combination of archaic and modern anatomical features, which was unexpected in the era 10,000 to 15,000 years ago, is discussed in connection with an analysis of the genome of 500 Africans. This analysis had revealed indications that around 35,000 years ago there could have been a mixture of anatomically modern humans with archaic relatives in Africa. Chris Stringer believes it is possible that the Iwo Eleru skull is evidence of the long-term survival of a Homo sapiens population that had separated from the ancestors of people living today decades ago. Katerina Havarti also interprets the find to mean "that the evolution of modern humans in Africa was a complex process and that populations of archaic hominins or their genes persisted in Africa longer than was previously thought." These interpretations became independent of another in 2014 conducted study confirmed; the anatomy of the skull indicates either a genetic intermingling with archaic people or the survival of a population with archaic skull features until the end of the Pleistocene .

Web links

Individual evidence

  1. ^ A b Don Brothwell and Thurstan Shaw : A Late Upper Pleistocene Proto-West African Negro from Nigeria. In: Man. New Series. Volume 6, No. 2, 1971, pp. 221-227, Introduction
  2. ↑ Phillip Allsworth-Jones et al .: The archaeological context of the Iwo Eleru cranium from Nigeria and preliminary results of new morphometric studies. In: P. Allsworth-Jones (Ed.): West African Archeology. New developments, new perspectives. BAR, S2164. Archaeopress, pp. 29–42, ISBN 978-1-4073-0708-4 , full text with numerous illustrations
  3. ^ Thurstan Shaw and SGH Daniels: Excavations at Iwo Eleru, Ondo State, Nigeria. In: West African Journal of Archeology. Volume 14, 1984, pp. 1-269, abstract
  4. ↑ Chris Stringer : Population relationships of later Pleistocene hominids: a multivariate study of available crania. In: Journal of Archaeological Science. Volume 1, No. 4, 1974, pp. 317-342, doi: 10.1016 / 0305-4403 (74) 90051-X
  5. ↑ Katerina Harvati , Chris Stringer et al .: The Later Stone Age Calvaria from Iwo Eleru, Nigeria: Morphology and Chronology. In: PLoS ONE. Volume 6, No. 9, 2011: e24024, doi: 10.1371 / journal.pone.0024024
  6. ↑ literally: “Our analysis indicates that Iwo Eleru possesses neurocranial morphology intermediate in shape between archaic hominins (Neanderthals and Homo erectus) and modern humans. This morphology is outside the range of modern human variability […], and is most similar […] to the early anatomically modern specimens from Skhul and Qafzeh. "Quoted from Harvati / Stringer et al., The Later Stone Age Calvaria from Iwo Eleru ...
  7. ↑ Michael F. Hammer et al .: Genetic evidence for archaic admixture in Africa. In: PNAS . Volume 108, No. 37. 2011, pp. 15123-15128, doi: 10.1073 / pnas.1109300108
  8. ^ Skull points to a more complex human evolution in Africa. On: bbc.co.uk of September 16, 2011
  9. ↑ Archaic Legacy in Modern Early Humans. On: idw-online.de from September 16, 2011
  10. ↑ Christopher M. Stojanowski: Iwo Eleru's place among Late Pleistocene and Early Holocene populations of North and East Africa. In: Journal of Human Evolution. Volume 75, 2014, pp. 80-89, doi: 10.1016 / j.jhevol.2014.02.018