Taung Child

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Taung Child
Australopithecus africanus - Cast of taung child.jpg
Catalog number Taung 1
Common name Taung Child
Species Australopithecus africanus
Age About 2.8 mya and 3.3 years when deceased
Place discovered Taung, South Africa
Date discovered 1924

The Taung Child (or Taung Baby) is the fossilised skull of a young Australopithecus africanus individual. It was discovered in 1924 by quarrymen working for the Northern Lime Company in Taung, South Africa. Raymond Dart described it as a new species in the journal Nature in 1925.

The skull is in repository at the University of Witwatersrand.[1]

History[edit]

In the early 20th century, the workers at limestone quarries in southern Africa routinely uncovered fossils from the tufa formations they mined. Many were of extinct fauna, which included baboons and other primates, and the more complete or somehow more interesting fossils were kept as curios by the Europeans that managed operations.[2]

In 1924, workers at the Buxton Limeworks near Taung, South Africa showed a fossilised primate skull to E.G. Izod, the visiting director of the Northern Lime Company, the managing company of the quarry. The director gave it to his son, Pat Izod, who displayed it on the mantle over the fireplace. When Josephine Salmons, a friend of the Izod family, paid a visit to Pat's home, she noticed the primate skull, identified it as from an extinct monkey, and realised its possible significance to her mentor, Raymond Dart.[2]

Josephine Salmons was the first female student of Dart, an anatomist at the University of Witwatersrand. Salmons was permitted to take the fossilised skull and presented it to Dart, who also recognised it as a significant find. Dart asked the company to send any more interesting fossilised skulls that should be unearthed. When a consulting geologist named Robert Young paid a visit to the quarry office, the director, A.E. Speirs, presented him with a collection of fossilised primate skulls that had been gathered by a miner known as Mr. De Bruyn. Young sent some of the skulls back to Dart.[2] When Dart examined the contents of the crate, he found a fossilised endocast of a skull, showing the impression of a complex brain, and matched it to a fossilised skull of a juvenile primate, which had a shallow face and fairly small teeth.[2] After a complete examination, he published the discovery in 1925, describing the new species of Australopithecus in the journal Nature. It was soon nicknamed the Taung Child.

The idea that the skull belonged to a new genus was identified by comparison with skulls of chimpanzees. The endocast of the Taung child was larger than a fully grown chimpanzee's. The forehead of the chimpanzee receded to form a heavy browridge and a jutting jaw; while the Taung child's forehead recedes, but leaves no browridge. The Taung child's foramen magnum (a void in the cranium where the spinal cord is continuous with the brain) is located beneath the cranium, showing that the creature stood upright.[3]

The British scientific establishment was at the time enamored with the hoax Piltdown Man, which had a large brain and ape-like teeth – the exact opposite of the Taung Child – and Dart's interpretation was not appreciated for decades.[4]

Criticism of Dart's research[edit]

After Dart presented the fossil of Australopithecus africanus, he received substantial criticism from scientists. Arthur Keith, one of the most prominent anatomists to comment on the fossil, said:

"[Dart's] claim is preposterous, the skull is that of a young anthropoid ape . . . and showing so many points of affinity with the two living African anthropoids, the gorilla and chimpanzee, that there cannot be a moment's hesitation in placing the fossil form in this living group".[5][verification needed]

Solly Zuckerman carried out studies of the Australopithecines family. Zuckerman thought that Australopithecus was little more than an ape. Zuckerman and a four-member team worked on the issue in the 1950s. Zuckerman decided that these creatures had not walked on two legs and were not an intermediate form between humans and apes. The concluding report by Zuckerman read:

"For my own part, the anatomical basis for the claim that the Australopithecines walked and ran upright like man is so much more flimsy than the evidence which points to the conclusion that their gait was some variant of what one sees in subhuman Primates, that it remains unacceptable".[6][verification needed]

Dean Falk, a specialist in neuroanatomy, noted that Dart had not fully considered certain apelike attributes for Taung.

"In his 1925 article, Dart had claimed that the brain of Taung was humanlike. As it turned out, he was wrong about that. . . . Taung's humanlike features were overemphasized".
"Like humans, other primates go through stages as they grow up. In his analysis of Taung, Dart did not fully appreciate that infant apes have not had time to develop features of the skull, such as thickened eyebrow ridges or attachment areas for heavy neck muscles, that set adult apes apart from human. Apparently he did not carefully consider the possibility that Taung's rounded forehead or the inferred position of the spinal cord might be due to the immaturity of the apelike specimen rather than to its resemblance to humans".

Subsequently, Falk unearthed an unpublished manuscript that Dart completed in 1929 in the Archives of the University of Witwatersrand, which provides a much more thorough description and analysis of the Taung endocast than Dart’s earlier announcement in Nature. Although Dart identified only two potential sulci on the Taung endocast in 1925, he identified and illustrated 14 additional sulci in this still unpublished monograph. In the unpublished manuscript, Dart detailed how Taung’s endocast was expanded globally in three different regions, contrary to the suggestion that he believed hominin brains evolved back-end-first, i.e., in a so-called mosaic fashion. Recently, Falk described the frontal lobe sulcal pattern on the Taung and other australopithecine endocasts, which is derived toward a humanlike pattern compared to that of apes.[7][8][9][10]

John Reader said that "Dart drew bold conclusions from his unavoidably limited observations".[11][verification needed]

Description[edit]

Taung-1 front
Philip V. Tobias and the Taung Child.

The fossil consists of most of the face and mandible with teeth and, uniquely, a natural endocast of the braincase. It is estimated to be 2.5 million years old. Originally thought to have been a monkey or ape, Dart realised that the skull would have been positioned directly above the spine, indicating an upright posture. This is a trait seen in humans, but not other primates.

The Taung Child was originally thought to be about six years old because of the presence of deciduous teeth, but is now believed to have been 3–4 based on studies of rates of enamel deposition. It was a creature standing 3' 6" (105 cm) and weighing about 20–24 pounds (9–11 kg). It had a cranial capacity of 400–500 cc[12] and lived mainly in a savanna habitat.

Examinations of the Taung Child fossil compared to that of an equivalent 9-year-old child suggest that A. africanus had a growth rate to adolescence more similar to that of modern apes like chimpanzees (genus Pan) than to that of modern Homo sapiens. However, intermediate species such as Homo ergaster/Homo erectus are thought to have gone through growth rates intermediate between modern humans and apes. This conclusion has mostly been based on the Turkana Boy fossil discovered in 1984.

In early 2006 it was announced that the Taung Child was probably killed by an eagle or similar large predatory bird. This conclusion was reached by noting similarities in the damage to the skull and eye sockets of the Taung Child with damage to the skulls of modern primates known to have been killed by eagles.[13]

In popular culture[edit]

A hologram of the skull appeared on the cover of the Nov. 1985 issue of National Geographic, in one of the pioneering uses of holograms in mass-market publications (a smaller hologram of an eagle had appeared on an earlier issue).[14]

Taung child – Recovering the missing parts of skull by Arc-Team, Antrocon NPO, Cicero Moraes, University of Padua
Taung child – Facial forensic reconstruction by Arc-Team, Antrocon NPO, Cicero Moraes, University of Padua

See also[edit]

References[edit]

  1. ^ Štrkalj, Goran; Kaszycka, Katarzyna (November/December 2012). "Shedding new light on an old mystery: Early photographs of the Taung Child". South African Journal of Science.
  2. ^ a b c d McKee, Jeffrey K. The Riddled Chain: Chance, Coincindence, and Chaos in Human Evolution. New Brunswick, NJ: Rutgers University Press. pp. 40–41. 
  3. ^ Fagan, Brian (11 February 1999). Eyewitness to Discovery: First-Person Accounts of More Than Fifty of the World's Greatest Archaeological Discoveries. Oxford University Press, USA. p. 512. ISBN 0195126513. 
  4. ^ Brain, C.K. Raymond Dart and our African Origins, in A Century of Nature: Twenty-One Discoveries that Changed Science and the World, Laura Garwin and Tim Lincoln, eds.
  5. ^ Johanson, David (1989). Lucy's Child. New York: William Morrow and Co. p. 56. 
  6. ^ Zuckerman, Solly (1970). Beyond the Ivory Tower. p. 93. 
  7. ^ Falk, Dean (2004). Braindance, Revised and Expanded Edition. New York: Henry Holt and Company. p. 13, 14. 
  8. ^ Falk, Dean (2009). The natural endocast of Taung (Australopithecus africanus): Insights from the unpublished papers of Raymond Arthur Dart. Yrbk. Phys. Anthropol., Series 52:49-65. 
  9. ^ Dart, R.A. (1929). Australopithecus africanus: And His Place in Human Nature. Unpublished manuscript in the University of Witwatersrand archives. 
  10. ^ Falk, Dean (2014). Interpreting sulci on hominin endocasts : Old hypotheses and new findings.. Frontiers in Human Neuroscience 8:134. doi: 10.3389/fnhum.2014.00134. 
  11. ^ Reader, John (1981). Missing Links. London: Book Club Associates/William Collins. 
  12. ^ Conroy, G. C., Falk, D., Guyer, J., Weber, G. W., Seidler, H. and Recheis, W. (2000), Endocranial capacity in Sts 71 (Australopithecus africanus) by three-dimensional computed tomography. Anat. Rec., 258: 391–396.
  13. ^ Downloadable 30-minute analysis by the BBC
  14. ^ National Geographic, volume 168, number 5, November 1985 [1]

External links[edit]