Florisbad Skull

Florisbad Skull
Common name Florisbad Skull
Species Archaic Homo sapiens
or Homo heidelbergensis
possibly Homo helmei
Age 259,000 yrs. old
Place discovered Florisbad archaeological and paleontological site, South Africa
Date discovered 1932
Discovered by Prof. T.F. Dreyer

The Florisbad Skull was originally discovered by T. F. Dreyer at the Florisbad site in 1932. Florisbad is a Middle Stone Age locality in Free State Province, South Africa. Florisbad ranks amongst the country's more important Middle Stone Age fossil localities because of the discovery of the largely intact archaic Homo Sapiens cranium and associated fauna.[1] The Florisbad Skull has often been classified as Homo helmei. According to Oppenheimer (2003), H. helmei was relatively the same size as modern humans, with a slightly larger brain volume of 1,400 cm3. They are associated with the start of the most important revolutions in human technology[2] The skull was also found with Middle Stone Age tools.[3]

The Florisbad skull comprises 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. In 1996, enamel samples from the tooth went through the electron spin resonance technique which allowed researchers to date the skull to around 259,000 years old[4]

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 carnivore activity[4]

Classification and dating

Dreyer classified the Florisbad Skull as Homo helmei to mark its distinctiveness from Homo sapiens fossils. It is now generally either described as "archaic H. sapiens" or assigned to H. heidelbergensis.[5] It may, however, be an intermediate form between H. heidelbergensis and H. sapiens, in which case retention of the H. helmei classification could be appropriate.[5]

According to Andrew Millard, paleoanthropology specialists do not know the dates of African and Near Eastern fossil hominids from the Middle and early Late Pleistocene as well as comparative analyses would assume.[6] Millard suggest that such specialists pay attention to "chronometric hygiene." This simply means weeding out bad dates for analyses. The Florisbad Skull is one specimen that is considered poorly handled within literature. Chronometric data continues to be hampered by an overreliance on secondary sources of literature. Often, a chain of citations exist and the original data is lost.[6] For example, one source cites the date for the Florisbad specimen to 259,000 years ago, plus or minus thirty-five years, which is attributed to the associated Florisbad fauna.[5] However, another group of researchers state that the Florisbad Skull has a maximum age of 250,000 years old (Stynder et al., 2001). Then, according to Brooks (2000), the age of the Florisbad Skull is 260,000 years old. Many times the initial proposed date of a specimen is based on comparisons of morphology to the best dated fossils at the time of that particular publication. According to Millard, each author should check the basis of previously cited dates, as well as do their own extensive research.[6]

Associated fauna

The Florisbad site has also produced a large and diverse fauna that is associated with the Florisbad cranium over several decades of research. 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 also suggests an open, grassland existed with a body of water in the immediate vicinity[1] 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

References

  1. 1 2 Lewis, Patrick J.; Brink, James S.; Kennedy, Alicia M.; Campbell, Timothy L. "Examination of the Florisbad microvertebrates". South African Journal of Science 107 (7/8). doi:10.4102/sajs.v107i7/8.613.
  2. ↑ "Homo helmei". Bradshaw Foundation. Retrieved 2015-11-18.
  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.
  4. 1 2 Schwartz, Jeffrey H.; Tattersall, Ian (2005-03-11). The Human Fossil Record, Craniodental Morphology of Genus Homo (Africa and Asia). John Wiley & Sons. ISBN 9780471326441.
  5. 1 2 3 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.
  6. 1 2 3 4 Millard, Andrew R. (2008-06-01). "A critique of the chronometric evidence for hominid fossils: I. Africa and the Near East 500–50 ka". Journal of Human Evolution 54 (6): 848–874. doi:10.1016/j.jhevol.2007.11.002.

Coordinates: 44°59′N 1°43′E / 44.983°N 1.717°E / 44.983; 1.717

This article is issued from Wikipedia - version of the Saturday, April 02, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.