Manot 1

Manot 1
Temporal range: Late Pleistocene,
0.049–0.060 Ma
↓
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Hominidae
Tribe: Hominini
Genus: Homo
Species: H. sapiens (archaic)

Manot 1 is a fossil specimen designated to a skullcap that represents an archaic modern human discovered in Israel.[1] It represents extinct humans called Manot people who lived in the Manot Cave (hence the name) in Western Galilee during the early Paleolithic period. It was discovered in 2008 and the scientific description was first published in an online edition of Nature on 28 January 2015.[2] Radiometric dating indicates that it is about 54,700 years old, which in turn shows that it is the oldest known specimen that belongs to modern human. In addition it is also a good evidence for the Out of Africa theory.[3] It also supports the idea that modern human ancestors could have interbred with another human species, the Neanderthals, as posited by genome analyses.

Discovery

Manot Cave under excavation in 2011

Manot 1 was discovered inside the Manot Cave when the cave itself was discovered in 2008. The cave is situated in Western Galilee, about 10 km north of the HaYonim Cave and 50 km northeast of Mt. Carmel Cave. It was discovered accidentally when a bulldozer cracked open its roof during construction work.[4] Archaeologists from the Cave Research Unit of Hebrew University of Jerusalem were immediately informed and made the initial survey. They found the skullcap alongside stone tools, charcoal pieces, and other human remains. Tools found included a Levallois point, burins, bladelets, overpassed blades, and Aurignacian tools. They also found remains of "fallow deer, red deer, mountain gazelle, horse, aurochs, hyena, and bear".[5] They reported it to the Israel Antiquities Authority (IAA), which granted another brief survey of the cave. The IAA granted a full-scale excavation in 2010. The excavation was conducted by a collaboration of archaeologists from Hebrew University of Jerusalem, Tel Aviv University, Geological Survey of Israel, Zinman Institute of Archaeology of University of Haifa, Kimmel Center for Archaeological Sciences of Weizmann Institute of Science, and the Department of Archaeology of Boston University.[5]

Description

Manot 1 is an adult individual represented by an almost complete skullcap (calvaria) very similar to those of modern humans. But it has a relatively small brain size, which is estimated at around 1,100 mL, compared to modern human brain which is about 1,400 mL.[1] Its unique features are the bun-shaped occipital, the moderate arch of the parietals, flat sagittal area, presence of a suprainiac fossa, and the pronounced superior nuchal line. These combined features indicate that it shares a number of features between the most recent African humans and those of European from the Upper Paleolithic period. But it has notable differences from those of other archaic humans found in the neighbouring Levant. The discoverers concluded that:

The overall shape and discrete morphological features of the Manot 1 calvaria demonstrate that this partial skull is unequivocally modern.[2]

Importance in human evolution

Manot 1 is the oldest modern human specimen found outside Africa, dated to 54,700 years old using uranium-thorium dating.[2] It supports the Out of Africa theory that modern humans originated and migrated from Africa around 60,000-70,000 years ago.[6][7] This concept has been so far only evidenced by genetic studies.[8][9] It is possible that it was among the ancestors of modern humans that started to colonise Europe.[10] Its period of existence falls within that of another extinct humans, the Neanderthals. Thus these two species lived side-by-side in the southern Levant. This implies that the Manot people could have interbred with the Neanderthals, the evidence that is so far supported only by comparative genome studies.[11][12] It is estimated that modern humans share as much as 2-4% Neanderthal genes. Genome sequence of a ~45,000-year-old modern human male from Siberia in 2014 showed that his ancestors interbred with Neanderthals around 52,000-58,000 years ago.[13] But no physical evidence placed humans geographically close to Neanderthals at the putative time of this interbreeding (genetic admixture). Manot 1 becomes the first hard evidence for such proximity at the right time. While extraction and sequencing of DNA from the remains could potentially confirm that interbreeding was occurring at that time, the odds of doing so successfully are reduced by the region's warm climate, which speeds up DNA degradation.[14][15]

References

  1. 1 2 Choi, Charles Q (28 January 2015). "55,000-Year-Old Skull Fragment May Be Linked to 1st Europeans". Live Science. Retrieved 4 February 2015.
  2. 1 2 3 Hershkovitz, Israel; Marder, Ofer; Ayalon, Avner; Bar-Matthews, Miryam; Yasur, Gal; Boaretto, Elisabetta; Caracuta, Valentina; Alex, Bridget; et al. (2015). "Levantine cranium from Manot Cave (Israel) foreshadows the first European modern humans". Nature. Epub ahead of print. doi:10.1038/nature14134. PMID 25629628.
  3. ↑ "55,000-Year-Old Skull Fossil Sheds New Light on Human Migration out of Africa". Science News. Retrieved 4 February 2015.
  4. ↑ "Archaeologists Reopen Investigation of Early Humans at Manot Cave in Israel". Popular Archaeology. 28 March 2013. Retrieved 4 February 2015.
  5. 1 2 Barzilai, O; Hershkovitz, I; Marder, O; Ayalon, A; Bar-Mathews, M; Bar-Oz, G; Boaretto, E; Berna, F; et al. (31 December 2012). "Manot Cave". Hadashot Arkheologiyot. The Israel Antiquities Authority. Retrieved 4 February 2015.
  6. ↑ David, Ariel (28 January 2015). "Oldest modern human remains outside Africa found in Israel". Haaretz.
  7. ↑ American Friends of Tel Aviv University (29 January 2015). "Ancient skull shows modern humans colonized Eurasia 60-70,000 years ago". ScienceDaily. Retrieved 2 February 2015.
  8. ↑ Comas, Iñaki; Coscolla, Mireia; Luo, Tao; Borrell, Sonia; Holt, Kathryn E; Kato-Maeda, Midori; Parkhill, Julian; Malla, Bijaya; et al. (2013). "Out-of-Africa migration and Neolithic coexpansion of Mycobacterium tuberculosis with modern humans". Nature Genetics. 45 (10): 1176–1182. doi:10.1038/ng.2744. PMC 3800747Freely accessible. PMID 23995134.
  9. ↑ Behar, Doron M.; Villems, Richard; Soodyall, Himla; Blue-Smith, Jason; Pereira, Luisa; Metspalu, Ene; Scozzari, Rosaria; Makkan, Heeran; et al. (2008). "The dawn of human matrilineal diversity". The American Journal of Human Genetics. 82 (5): 1130–1140. doi:10.1016/j.ajhg.2008.04.002. PMC 2427203Freely accessible. PMID 18439549.
  10. ↑ Wilford, John Noble (28 January 2015). "Skull Fossil Offers New Clues on Human Journey From Africa". The New York Times. Retrieved 4 February 2015.
  11. ↑ Sankararaman, Sriram; Patterson, Nick; Li, Heng; Pääbo, Svante; Reich, David; Akey, Joshua M. (2012). "The date of interbreeding between Neandertals and modern humans". PLoS Genetics. 8 (10): e1002947. doi:10.1371/journal.pgen.1002947. PMC 3464203Freely accessible. PMID 23055938.
  12. ↑ Wang, S.; Lachance, J.; Tishkoff, S. A.; Hey, J.; Xing, J. (2013). "Apparent variation in Neanderthal admixture among African populations is consistent with gene flow from Non-African populations". Genome Biology and Evolution. 5 (11): 2075–2081. doi:10.1093/gbe/evt160. PMC 3845641Freely accessible. PMID 24162011.
  13. ↑ Fu, Qiaomei; Li, Heng; Moorjani, Priya; Jay, Flora; Slepchenko, Sergey M.; Bondarev, Aleksei A.; Johnson, Philip L. F.; Aximu-Petri, Ayinuer; et al. (2014). "Genome sequence of a 45,000-year-old modern human from western Siberia". Nature. 514 (7523): 445–449. doi:10.1038/nature13810. PMID 25341783.
  14. ↑ Miller, Rose (28 January 2015). "This skull may provide a new link between Neanderthals and modern humans". The Verge. Retrieved 4 February 2015.
  15. ↑ Callaway, Ewen (29 January 2015). "New Skull Could Be from Human Group that Interbred with Neandertals". Scientific American. Retrieved 4 February 2015.
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