Florisbad Skull

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Florisbad Skull
Florisbad-Helmei-Homo heidelbergensis.jpg
Common nameFlorisbad Skull
SpeciesHomo helmei
or Homo sapiens
or Homo heidelbergensis
Age259±35 ka
Place discoveredFlorisbad archaeological and paleontological site, South Africa
Date discovered1932
Discovered byThomas F. Dreyer, G. Venter[1]

The Florisbad Skull is an important human fossil of the early Middle Stone Age, representing either late Homo heidelbergensis or early Homo sapiens. It was discovered in 1932 by T. F. Dreyer at the Florisbad site, Free State Province, South Africa.

Classification[edit]

The Florisbad Skull was classified as Homo (Africanthropus) helmei by Dreyer (1935), after the sponsor of Dreyer's expedition, R. E. Helme. The Africanthropus generic name proposed by Dreyer was taken up by Weinert (1938) to refer to early African human fossils. In a note to Dreyer's 1935 publication, C. U. Ariëns Kappers mentioned the close resemblance of the fossil to Homo sapiens fossilis (Cro-Magnon Man). M. R. Drennan (1935, 1937) emphasized resemblance to Homo neanderthalensis, proposing is classification as Homo florisbadensis (helmei). A. Galloway (1937) proposed classification as Homo sapiens, specifically noting a resemblance to modern Australoids. Commentators of the 1950s to 1970s have drawn attention to archaic African human fossils such as Saldanha and Kabwe crania (now assigned to H. heidelbergensis). Clarke (1985) compared it to Laetoli Hominid 18 and Omo 2, which are now considered early anatomically modern human (H. sapiens) fossils. The difficulty of placing the fossil in either H. heidelbergensis or H. sapiens have prompted McBrearty and Brooks (2000) to revive the designation H. helmei.[1] Scerri et al. (2018) adduce the fossil as evidence for "African multiregionalism", the view of a complex speciation of H. sapiens widely dispersed across Africa, with substantial hybridization between H. sapiens and more divergent hominins in different regions.[2]

Description[edit]

The Florisbad Skull belonged to a specimen within the size range of modern humans, with a brain volume larger than modern averages, at 1,400 cm3. The skull was also found with Middle Stone Age tools.[3]

The fossil skull is a fragment, preserved are the right side of the face, most of the frontal bone, and some of the maxilla, along with portions of the roof and sidewalls. A single, upper right, third molar was also found with the adult skull.

The skull also showed extensive porotic hyperostosis as well as a large number of healed lesions, including pathological drainage or vascular tracts. There are also a couple of large puncture marks and scratch-like marks which may reflect hyena chewing.[4]

Based on enamel samples from the tooth found with the skull, the fossil has been directly dated by electron spin resonance dating to around between 259±35 ka (between 294,000 and 224,000 years old).[4]

Context[edit]

The partial cranium is part of an assemblage of mostly carnivore prey remains, caught in vertical spring vents. It shows damage by hyena chewing. The spring vents were later sealed by deposits. "Peat II" is a deposit of dark organic clay representing a Middle Stone Age land surface, showing a human occupation horizon dated 121±6 ka.[4]

The wider Florisbad site has also produced a large and diverse fauna. The assemblage including micro-vertebrates from springhares, rabbits, rodents and reptiles has informed researchers on the paleoenvironment of the interior of South Africa in the Middle Pleistocene. The large mammal component of the site suggests an open grassland with a body of water in the immediate vicinity.[5] Although many specimens are dated by comparisons of faunal assemblages, this method does not prove to have accurate chronological resolution for much of the last million years.[6]

See also[edit]

References[edit]

  1. ^ a b Schwartz, Jeffrey H.; Tattersall, Ian (2005-03-11). The Human Fossil Record, Craniodental Morphology of Genus Homo (Africa and Asia). John Wiley & Sons. p. 79–81. ISBN 9780471326441..
  2. ^ "Other early H. sapiens fossils from Florisbad in South Africa (∼260 ka), Omo Kibish (∼195 ka) and Herto (∼160 ka), both in Ethiopia, are morphologically diverse. This diversity has led some researchers to propose that fossils such as Jebel Irhoud and Florisbad actually represent a more primitive species called ‘H. helmei’, using the binomen given to the Florisbad partial cranium in 1935." Scerri, M.L., et al., "Did Our Species Evolve in Subdivided Populations across Africa, and Why Does It Matter?" Trends in Ecology & Evolution 33(8), August 2018, 582–594, doi:10.1016/j.tree.2018.05.005.
  3. ^ Rightmire, G. Philip (2009-09-22). "Middle and later Pleistocene hominins in Africa and Southwest Asia". Proceedings of the National Academy of Sciences. 106 (38): 16046–16050. doi:10.1073/pnas.0903930106. ISSN 0027-8424. PMC 2752549. PMID 19581595. "Homo helmei". Bradshaw Foundation. Retrieved 2015-11-18.
  4. ^ a b c Grün, Rainer; Brink, James S.; Spooner, Nigel A.; Taylor, Lois; Stringer, Chris B.; Franciscus, Robert G.; Murray, Andrew S. (1996-08-08). "Direct dating of Florisbad hominid". Nature. 382 (6591): 500–501. doi:10.1038/382500a0. PMID 8700221..
  5. ^ Lewis, Patrick J.; Brink, James S.; Kennedy, Alicia M.; Campbell, Timothy L. (2011). "Examination of the Florisbad microvertebrates". South African Journal of Science. 107 (7/8). doi:10.4102/sajs.v107i7/8.613.
  6. ^ Millard, A.R. (2009). A critique of the chronometric evidence for hominid fossils: I. Africa and the Near East 500-50 ka. J Hum Evol. 2008 54:848-874.

External links[edit]

Coordinates: 28°46′S 26°04′E / 28.767°S 26.067°E / -28.767; 26.067