Djebel Irhoud

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Reconstruction of a skull based on computed tomographic analyzes of several fossils

Djebel Irhoud ( Arabic جبل إيغود, DMG Ǧabal Īġūd , also: Jebel Irhoud, Jebel Ighoud) is an archaeological and palaeoanthropological cave discovery site in Morocco . The karst cave, discovered in 1960 during the mining of barite , is located near Sidi Mokhtar , around 100 kilometers northwest of Marrakech and 55 km southeast of Safi .

It was there in 2017 that the oldest fossils attributed to anatomically modern humans ( Homo sapiens ), around 300,000 years old, were discovered.

Finds

The Irhoud 1 fossil ( replica )
Jean-Jacques Hublin points to the eye sockets of the Irhoud 10 fossil, which is still untouched in the ground.
After exposure: In the center of the picture, due to the yellowish discoloration, the skull of Irhoud 10 stands out from the surrounding rock. Scale in cm.

As early as 1961, during the excavations carried out by Émile Ennouchi, a largely preserved hominine skull of an adult was discovered (Irhoud 1), and a skull was recovered two years later (Irhoud 2); Both finds were initially interpreted as a North African Neanderthal , as the stone tools found in Djebel Irhoud mainly show features of the Levallois technique, which was ascribed to the Neanderthals in North Africa in the 1960s. It has only recently been discussed that Levallois types of the early Middle Stone Age in Africa formed the starting point for a separate development: while such tools in sub-Saharan Africa are associated with Homo sapiens , in Europe Neanderthals developed the Levallois concept further independently. North Africa and the Levant are indifferent to the assignment of stone tools to human types, as the finds from Djebel Irhoud or from Skhul in Israel show.

In 1968 the Irhoud 3 fossil, the lower jaw of a child with well-preserved teeth, was recovered. Four other, less informative hominine fossils were recovered in the years that followed, including the humerus of a child (Irhoud 4) as well as the iliac bone of a youth and a fragment of a lower jaw. In 1981, a detailed analysis of the lower jaw Irhoud 3 revealed that the fossils cannot be assigned to the Neanderthals, but belong to early anatomically modern humans and were possibly their earliest representatives in the Maghreb . They are therefore possibly forerunners of the much younger hominine fossils associated with the culture des Atérien from the Dar es Soltane II site on the Atlantic coast near Rabat ; The Dar es Soltane 5 skull in particular has features similar to those of the Irhoud 1 and 2 skulls.

However, it was initially unclear how the striking combination of original anatomical features and “modern” anatomical features should be interpreted, which, due to the good state of preservation of Irhoud 1, was considered reliable at an early stage. Only several new finds described in 2017 solved the riddle: Embedded in an undisturbed find horizon , which made reliable dating possible, in 2007 there were five related fragments of an adult's skull (Irhoud 10) with partially preserved bones of the face and one almost complete preserved lower jaw (Irhoud 11) recovered; also came u. a. an upper jaw fragment (Irhoud 21, recovered in 2011) as well as various tooth fragments and bones from the area below the head. The horizon known as Layer 7 therefore contained the remains of at least five individuals (three adults, one adolescent and one child aged seven to eight years), whose bones, according to the description in the journal Nature , were embedded at the site within a relatively short period of time. Once again, the characteristics of the fossils were interpreted as a mosaic of original (typical for the ancestors of Homo sapiens ) characteristics and features of Homo sapiens : the face, lower jaw and teeth show characteristics of anatomically modern humans, the elongated ( Homo sapiens rounded) rear area the skullcap looks archaic. The new dating, which classifies all bone finds from a much older era, made this mosaic form plausible.

Dating

Stone device from Layer 7 (scale: 1 cm)

The dating methods that were available in the 1960s initially did not provide reliable results for the hominine bones; In 1962 the age of the finds was estimated to be 40,000 years, in 1991 an age of around 100,000 years was derived from horse teeth from a comparable find position. The studies started in 2004 by a working group led by Jean-Jacques Hublin showed an age of 160,000 ± 16,000 years in 2007, which roughly corresponds to the age of the fossils Omo 1 and Omo 2 and the so-called Herto skull from Ethiopia . In 2013, an exact description of the rodents recovered from the fossilized layers was interpreted as evidence that the finds are significantly older than assumed in the early 1960s and can be dated to the Middle Pleistocene .

The dating of the find horizon of the fossils Irhoud 10 and 11 first described in 2017 with the help of thermoluminescence finally revealed an age of 315,000 ± 34,000 years. Various stone utensils made of flint , which were discovered together with the bones and were strongly heated at the time of their deposition , could be used for dating . According to this dating, the finds from Djebel Irhoud are the oldest fossils that have so far been identified as belonging to the archaic Homo sapiens . Human teeth from the Qesem Cave in Israel have been dated to around the same age, although their stratification is not generally recognized.

Anthropological Findings

The examinations carried out in 2007 by the Max Planck Institute for Evolutionary Anthropology in Leipzig with the synchrotron on a lower tooth of the Irhoud 3 fossil also provided information about the life history of a child of early anatomically modern humans. The results suggest a long childhood - the associated development of the brain and a simultaneous socialization process should therefore have been of decisive importance in the earliest Homo sapiens .

The analysis of the skull bones presented in 2017 also provided indications of the evolution of their externally visible features and - derived from this - the changes in the brain structure. The “modern” looking face and the equally “modern” looking teeth therefore developed much earlier in the course of human tribal history than the round bony covering of the brain typical of Homo sapiens ; the authors of the study therefore suspect that the shape of the brain and possibly also the functions of the brain emerged relatively late. Excavation director Hublin also pointed out that the finds from Morocco indicate that anatomically modern humans developed not only in a single region of Africa, but that the entire continent was the " cradle of mankind ".

Together with the hominine fossils and the stone utensils, numerous fossil animal bones were recovered, especially long bones , which were interpreted as an indication of the food of the cave dwellers due to cut marks: According to this, gazelles ( Gazella atlantica , Gazella cuvieri and Gazella tingitana ) were primarily hunted at the time . but also zebras , hartebeest and aurochs , and occasionally were ostriches grade eggs and fresh - mussels - and worm eaten.

See also

literature

  • Jean-Jacques Hublin : Northwestern African Middle Pleistocene hominids and their bearing on the emergence of Homo sapiens. In: Lawrence Barham, Kate Kate Robson-Brown: Africa and Asia in the Middle Pleistocene. Western Academic & Specialist Press Ltd, Bristol 2001, pp. 110-114. ISBN 978-0953541843 , full text (PDF; 2.4 MB)

Web links

Individual evidence

  1. ↑ a b Jean-Jacques Hublin : Recent Human Evolution in North West Africa. In: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences. Volume 337, No. 1280, 1992, pp. 185–191, doi: 10.1098 / rstb.1992.0096 , full text (PDF; 1.4 MB) ( Memento from 14 May 2011 in the Internet Archive )
  2. ↑ a b c d Daniel Richter, Rainer Grün, Renaud Joannes-Boyau, Teresa E. Steele, Fethi Amani, Mathieu Rué, Paul Fernandes, Jean-Paul Raynal, Denis Geraads, Abdelouahed Ben-Ncer, Jean-Jacques Hublin, Shannon P McPherron: The age of the hominin fossils from Jebel Irhoud, Morocco, and the origins of the Middle Stone Age . In: Nature . Volume 546, No. 7657, June 8, 2017, ISSN  0028-0836 , pp. 293-296. doi : 10.1038 / nature22335 . (English)
  3. ↑ Emile Ennouchi: Le deuxième crâne de l'homme d'Irhoud. In: Annales de Paléontologie (Vértébrés). Volume 54, 1968, pp. 117-128.
  4. ↑ a b Émile Ennouchi: Un neandertalien: L'Homme du Jebel Irhoud (Maroc). In: Anthropology. Volume 66, 1962, pp. 279-299
  5. ↑ Émile Ennouchi: Un crâne d'Homme ancien au Jebel Irhoud (Maroc). In: Comptes Rendus de l'Académie des Sciences. Volume 254, 1962, pp. 4330-4332
    Émile Ennouchi: Les néandertaliens du Jebel Irhoud (Maroc). In: Comptes Rendus de l'Académie des Sciences. Volume 256, 1963, pp. 2459-2460.
  6. ↑ Robert Foley, Marta Mirazón Lahr: Mode 3 Technologies and the Evolution of Modern Humans . In: Cambridge Archaeological Journal . 7, No. 01, 2008, ISSN  0959-7743 , p. 3. doi : 10.1017 / S0959774300001451 .
  7. ↑ Émile Ennouchi: Présence d'un enfant néandertalien au Jebel Irhoud (Maroc). In: Annales de Paleontologie (Vertebres). Vol. 55, 1969, pp. 251-265.
  8. ^ Jean-Jacques Hublin, Anne-Marie Tillier and Jacques Tixier: L'humerus d'enfant moustérien (Homo 4) du Jebel Irhoud (Maroc) dans son contexte archéologique. In: Bulletins et Mémoires de la Société d'anthropologie de Paris. Volume 4, No. 2, 1987, pp. 115–141, full text (PDF)
  9. ↑ Fethi Amani and Denis Geraads: Le gisement du Moustérien Jebel Irhoud, Maroc: Precisions sur la faune et la biochronology, et description d'un nouveau reste humain. In: Comptes Rendus de l'Académie des Sciences de Paris. Volume 316, Series II, 1993, pp. 847-852, full text (PDF
  10. ^ Jean-Jacques Hublin and Anne-Marie Tillier: Les enfants moustériens de Jebel Irhoud (Maroc), comparaison avec les néandertaliens juvéniles d'Europe. In: Bulletins et Mémoires de la Société d'anthropologie de Paris. Volume 5, Series 14, No. 4, 1988, pp. 237–246, full text (PDF .
  11. ^ Jean-Jacques Hublin and Anne-Marie Tillier: The Mousterian juvenile mandible from Irhoud (Morocco): A phylogenetic interpretation. In: Chris Stringer (Ed.): Aspects of Human Evolution. Symposia of the Society for the Study of Human Biology. Volume 21, Taylor & Francis, London 1981, pp. 167–185, full text (PDF; 5.3 MB) with numerous illustrations ( Memento of May 14, 2011 in the Internet Archive )
  12. ↑ André Debénath: Découverte de restes humains probablement atériens à Dar es Soltane (Maroc) . In: Comptes Rendus de l'Académie des Sciences. Volume 281, 1975, pp. 875-876.
  13. ↑ Emiliano Bruner and Osbjorn Pearson: Neurocranial evolution humans in modern: the case of Jebel Irhoud 1. In: Anthropological Science. Volume 121, No. 1, 2013, pp. 31–41, doi: 10.1537 / ase.120927 , full text (PDF)
  14. ^ A b Jean-Jacques Hublin, Abdelouahed Ben-Ncer, Shara E. Bailey, Sarah E. Freidline, Simon Neubauer, Matthew M. Skinner, Inga Bergmann, Adeline Le Cabec, Stefano Benazzi, Katerina Harvati, Philipp Gunz: New fossils from Jebel Irhoud, Morocco and the pan-African origin of Homo sapiens . In: Nature . Volume 546, No. 7657, June 8, 2017, ISSN  0028-0836 , pp. 289-292. doi : 10.1038 / nature22336 . (English)
  15. ↑ Extended Data Table 1: List of hominin specimens. On: nature.com from June 8, 2017
  16. ^ A b Tanya M. Smith et al .: Earliest evidence of modern human life history in North African early Homo sapiens. In: PNAS . Volume 104, No. 15, 2007, pp. 6128-6133, doi: 10.1073 / pnas.0700747104 .
  17. ↑ Denis Geraads et al .: The rodents from the late middle Pleistocene hominid bearing site of J'bel Irhoud, Morocco, and their chronological and paleoenvironmental implications. In: Quaternary Research. Volume 80, 2013, pp. 552-561, doi: 10.1016 / j.yqres.2013.08.003
  18. ↑ Analysis of fossil teeth of a Homo sapiens: A long childhood ... ( Memento from March 20, 2007 in the Internet Archive ) In: nzz.ch , March 14, 2007
  19. ↑ Harald Rösch: Homo sapiens is older than expected. Researchers are discovering the oldest fossils of our kind in Morocco . In: idw-online.de , Informationsdienst Wissenschaft eV -idw-, June 7, 2017, accessed on June 8, 2017.
  20. ↑ Oldest Homo sapiens fossil claim rewrites our species' history. On: nature.com from June 7, 2017
  21. ^ Supplementary Information. In: nature.com . June 7, 2017, p. 6 ff.
    Moroccan fossils show human ancestors' diet of game. In: eurekalert.org . June 7, 2017 (English).

Coordinates: 31 ° 51 ′ 17.9 ″  N , 8 ° 52 ′ 21 ″  W.