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→Cold-adapted theory: removed contradictory claim which was not supported by the citation. The source text only mentions Neanderthals as "Nasal form in Neanderthals has also been interpreted as an adaptation to cold by several authors"
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===Cold-adapted theory===
===Cold-adapted theory===
Some people thought that the large Neanderthal noses were an adaptation to the cold,<ref>{{cite book | last = Finlayson | first = C | title = Neanderthals and modern humans: an ecological and evolutionary perspective | publisher = [[Cambridge University Press]] | year = 2004 | isbn = 0-521-82087-1 | pages = [http://books.google.com/books?id=TmQ4i1EQ4AYC&pg=PA84 84] }}</ref> but primate and arctic animal studies have shown sinus size reduction in areas of extreme cold rather than enlargement in accordance with [[Allen's rule]].<ref name="Rae" /> Todd C. Rae summarizes explanations about Neanderthal anatomy as trying to find explanations for the "paradox" that their traits are not cold-adapted.<ref name="Rae" /> Therefore Rae concludes that the design of the large and extensive Neanderthal nose was evolved for the hotter climate of the Middle East and went unchanged when the Neanderthals entered Europe.<ref name="Rae">{{Cite journal | last1 = Rae | first1 = TC. | last2 = Koppe | first2 = T. | last3 = Stringer | first3 = CB. | title = The Neanderthal face is not cold adapted | journal = J Hum Evol | volume = 60 | issue = 2 | pages = 234–9 |date=Feb 2011 | doi = 10.1016/j.jhevol.2010.10.003 | pmid = 21183202 }}
Some people thought that the large Neanderthal noses were an adaptation to the cold,<ref>{{cite book | last = Finlayson | first = C | title = Neanderthals and modern humans: an ecological and evolutionary perspective | publisher = [[Cambridge University Press]] | year = 2004 | isbn = 0-521-82087-1 | pages = [http://books.google.com/books?id=TmQ4i1EQ4AYC&pg=PA84 84] }}</ref> but primate and arctic animal studies have shown sinus size reduction in areas of extreme cold rather than enlargement in accordance with [[Allen's rule]].<ref name="Rae" /> Todd C. Rae summarizes explanations about Neanderthal anatomy as trying to find explanations for the "paradox" that their traits are not cold-adapted.<ref name="Rae" /> Therefore Rae concludes that the design of the large and extensive Neanderthal nose was evolved for the hotter climate of the Middle East and went unchanged when the Neanderthals entered Europe.<ref name="Rae">{{Cite journal | last1 = Rae | first1 = TC. | last2 = Koppe | first2 = T. | last3 = Stringer | first3 = CB. | title = The Neanderthal face is not cold adapted | journal = J Hum Evol | volume = 60 | issue = 2 | pages = 234–9 |date=Feb 2011 | doi = 10.1016/j.jhevol.2010.10.003 | pmid = 21183202 }}</ref>


==Pathology==
==Pathology==

Revision as of 21:24, 29 January 2014

Neanderthal
Temporal range: Middle to Late Pleistocene, 0.6–0.03 Ma
↓
Mounted Neanderthal skeleton, American Museum of Natural History
Scientific classification
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Primates
Family:
Hominidae
Genus:
Homo
Species:
H. neanderthalensis
Binomial name
Homo neanderthalensis
King, 1864
Synonyms

Neanderthal anatomy differed from modern humans in that they had a more robust build and distinctive morphological features, especially on the cranium, which gradually accumulated more derived aspects, particularly in certain isolated geographic regions. Evidence suggests they were much stronger than modern humans[1] while they were comparable in height; based on 45 long bones from at most 14 males and 7 females, Neanderthal males averaged 164–168 cm (65–66 in) and females 152–156 cm (60–61 in) tall.[2] Samples of 26 specimens in 2010 found an average weight of 77.6 kg (171 lb) for males and 66.4 kg (146 lb) for females.[3] A 2007 genetic study suggested some Neanderthals may have had red hair and light skin color.[4][5]

Distinguishing physical traits

Ashley Montagu claimed humans have more neotenized skulls than Neanderthals.[6]
Neanderthal cranial anatomy
Neanderthal footprint in the Natural History Museum in Prague
File:Kermanshah Pal Museum-Neanderthal.jpg
A reconstruction of a Neanderthal male at Zagros Paleolithic Museum (2008)

The magnitude of autapomorphic traits in specimens differ in time. In the latest specimens, autapomorphy is unclear. The following is a list of physical traits that distinguish Neanderthals from modern humans. However, not all of them distinguish specific Neanderthal populations from various geographic areas, evolutionary periods, or other extinct humans. Also, many of these traits occasionally manifest in modern humans, particularly among certain ethnic groups traced to Neanderthal habitat ranges.[citation needed] Nothing is certain (from unearthed bones) about the shape of soft parts such as eyes, ears, and lips of Neanderthals.[7]

While the structure of the head and face were not very far removed from those of modern humans, there were still quite noticeable differences. Notably the modern human head is shorter, with a less pronounced facial front. The Neanderthal chin and forehead sloped backwards and the nose region protruded forward more than in modern humans. The common shapes of the nose are not known but in general it was likely more robust, and possibly slightly larger, than in modern humans. The brain space of the skull, and so most likely the brain itself, were larger than in modern humans.

When comparing traits to worldwide average present day human traits in Neanderthal specimens, the following traits are distinguished. The magnitude on particular trait changes with 300,000 years timeline. The large number of classic Neanderthal traits is significant because extreme examples of Homo sapiens may sometimes show one or more of these traits, but not most or all of them.

Cold-adapted theory

Some people thought that the large Neanderthal noses were an adaptation to the cold,[13] but primate and arctic animal studies have shown sinus size reduction in areas of extreme cold rather than enlargement in accordance with Allen's rule.[14] Todd C. Rae summarizes explanations about Neanderthal anatomy as trying to find explanations for the "paradox" that their traits are not cold-adapted.[14] Therefore Rae concludes that the design of the large and extensive Neanderthal nose was evolved for the hotter climate of the Middle East and went unchanged when the Neanderthals entered Europe.[14]

Pathology

Within the west Asian and European record, there are five broad groups of pathology or injury noted in Neanderthal skeletons.

Fractures

Neanderthals seemed to suffer a high frequency of fractures, especially common on the ribs (Shanidar IV, La Chapelle-aux-Saints 1 ('Old Man'), the femur (La Ferrassie 1), fibulae (La Ferrassie 2 and Tabun 1), spine (Kebara 2) and skull (Shanidar I, Krapina, Sala 1). These fractures are often healed and show little or no sign of infection, suggesting that injured individuals were cared for during times of incapacitation. It has been remarked that Neanderthals showed a frequency of such injuries comparable to that of modern rodeo professionals, showing frequent contact with large, combative mammals. The pattern of fractures, along with the absence of throwing weapons, suggests that they may have hunted by leaping onto their prey and stabbing or even wrestling it to the ground.[15]

Trauma

Particularly related to fractures are cases of trauma seen on many skeletons of Neanderthals. These usually take the form of stab wounds, as seen on Shanidar III, whose lung was probably punctured by a stab wound to the chest between the eighth and ninth ribs. This may have been an intentional attack or merely a hunting accident; either way the man survived for some weeks after his injury before being killed by a rock fall in the Shanidar cave. Other signs of trauma include blows to the head (Shanidar I and IV, Krapina), all of which seemed to have healed, although traces of the scalp wounds are visible on the surface of the skulls.

Degenerative disease

Arthritis was common in the older Neanderthal population, specifically targeting areas of articulation such as the ankle (Shanidar III), spine and hips (La Chapelle-aux-Saints 'Old Man'), arms (La Quina 5, Krapina, Feldhofer) knees, fingers and toes. This is closely related to degenerative joint disease, which can range from normal, use-related degeneration to painful, debilitating restriction of movement and deformity and is seen in varying degree in the Shanidar skeletons (I–IV).

Developmental Stress

Neanderthal child

Two non-specific indicators of stress during development are found in teeth, which record stresses, such as periods of food scarcity or illness, that disrupt normal dental growth. One indicator is enamel hypoplasia, which appears as pits, grooves, or lines in the hard enamel covering of teeth. The other indicator, fluctuating asymmetry, manifests as random departures from symmetry in paired biological structures (such as right and left teeth). Teeth do not grow in size after they form nor do they produce new enamel, so enamel hypoplasia and fluctuating asymmetry provide a permanent record of developmental stresses occurring in infancy and childhood. A study of 669 Neanderthal crowns showed that 75% of individuals suffered some degree of hypoplasia. Two studies [,[16][17]] compared Neanderthals with the Tigara, coastal whale-hunting people from Point Hope Alaska, finding comparable levels of linear enamel hypoplasia (a specific form of hypoplasia) and higher levels of fluctuating asymmetry in Neanderthals. Estimated stress episode duration from Neanderthal linear enamel hyoplasias suggest that Neandertals experienced stresses lasting from two weeks to up to three months.

Infection

Evidence of infections on Neanderthal skeletons is usually visible in the form of lesions on the bone, which are created by systemic infection on areas closest to the bone. Shanidar I has evidence of the degenerative lesions as does La Ferrassie 1, whose lesions on both femora, tibiae and fibulae are indicative of a systemic infection or carcinoma (malignant tumour/cancer).

Childhood

Neanderthal children may have grown faster than modern human children. Modern humans have the slowest body growth of any mammal during childhood (the period between infancy and puberty) with lack of growth during this period being made up later in an adolescent growth spurt.[18][19][20] The possibility that Neanderthal childhood growth was different was first raised in 1928 by the excavators of the Mousterian rock-shelter of a Neanderthal juvenile.[21] Arthur Keith in 1931 wrote, "Apparently Neanderthal children assumed the appearances of maturity at an earlier age than modern children."[22] The rate of body maturation can be inferred by comparing the maturity of a juvenile's fossil remains and the estimated age of death.

The age at which juveniles die can be indirectly inferred from their tooth morphology, development and emergence. This has been argued to both support[23] and question[24][25] the existence of a maturation difference between Neanderthals and modern humans. Since 2007, tooth age can be directly calculated using the noninvasive imaging of growth patterns in tooth enamel by means of x-ray synchrotron microtomography.[26]

This research supports the occurrence of much more rapid physical development in Neanderthals than in modern human children.[27] The x-ray synchrotron microtomography study of early H. sapiens sapiens argues that this difference existed between the two species as far back as 160,000 years before present.[28]

Footnotes

  1. ^ "Neanderthal". BBC. Retrieved 18 May 2009.
  2. ^ Helmuth H (1998). "Body height, body mass and surface area of the Neanderthals". Zeitschrift Für Morphologie Und Anthropologie. 82 (1): 1–12. PMID 9850627.
  3. ^ Froehle, Andrew W; Chruchill, Steven E (2009). "Energetic Competition Between Neandertals and Anatomically Modern Humans" (PDF). PaleoAnthropology: 96–116. Retrieved 31 October 2011.
  4. ^ Laleuza-Fox, Carles (25 October 2007). "A Melanocortin 1 Receptor Allele Suggests Varying Pigmentation Among Neanderthals". Science. 318 (5855): 1453–5. doi:10.1126/science.1147417. PMID 17962522. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  5. ^ Rincon, Paul (25 October 2007). "Neanderthals 'were flame-haired'". BBC News. Retrieved 25 October 2007.
  6. ^ a b Montagu, A. (1989). Growing Young. Bergin & Garvey: CT.
  7. ^ Carey, Bjorn (10 March 2005). "Scientists Build 'Frankenstein' Neanderthal Skeleton". LiveScience. Retrieved 18 May 2009.
  8. ^ Gunz, P; Harvati, K (March 2007). "The Neanderthal "chignon": variation, integration, and homology" (PDF). Journal of Human Evolution. 52 (3): 262–74. doi:10.1016/j.jhevol.2006.08.010. ISSN 0047-2484. PMID 17097133.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  9. ^ http://www.pajamacore.org/writings/origins.php[dead link]
  10. ^ Bower, Bruce (11 April 1992). "Neanderthals to investigators: can we talk? – vocal abilities in pre-historic humans". Science News. Retrieved 18 May 2009.
  11. ^ Arensburg, B; Schepartz, La; Tillier, Am; Vandermeersch, B; Rak, Y (October 1990). "A reappraisal of the anatomical basis for speech in Middle Palaeolithic hominids". American Journal of Physical Anthropology. 83 (2): 137–46. doi:10.1002/ajpa.1330830202. ISSN 0002-9483. PMID 2248373.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  12. ^ a b De Groote, Isabelle (October 2011). "The Neanderthal lower arm". J Hum Evol. 61 (4): 396–410. doi:10.1016/j.jhevol.2011.05.007. PMID 21762953.
  13. ^ Finlayson, C (2004). Neanderthals and modern humans: an ecological and evolutionary perspective. Cambridge University Press. pp. 84. ISBN 0-521-82087-1.
  14. ^ a b c Rae, TC.; Koppe, T.; Stringer, CB. (February 2011). "The Neanderthal face is not cold adapted". J Hum Evol. 60 (2): 234–9. doi:10.1016/j.jhevol.2010.10.003. PMID 21183202.
  15. ^ T.D. Berger and E. Trinkaus (1995). "Patterns of trauma among Neadertals". Journal of Archaeological Science. 22 (6): 841–852. doi:10.1016/0305-4403(95)90013-6. Retrieved 28 June 2007.
  16. ^ Guatelli-Steinberg, D., Larsen C.S., and Hutchinson D. L. (2004). "Prevalence and the duration linear enamel hypoplasia: A comparative study of Neandertals and Inuit foragers". Journal of Human Evolution. 47: 65–84.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  17. ^ Barrett, C.K., Guatelli-Steinberg, D., and Sciulli, P.W. (2012). "Revisiting dental fluctuating asymmetry in Neandertals and modern humans". American Journal of Physical Anthropology. 149: 193–204.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  18. ^ Walker R, Hill K, Burger O, Hurtado AM (April 2006). "Life in the slow lane revisited: ontogenetic separation between chimpanzees and humans". American Journal of Physical Anthropology. 129 (4): 577–83. doi:10.1002/ajpa.20306. PMID 16345067.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  19. ^ Bogin, Barry (1997). m682 "Evolutionary hypotheses for human childhood". American Journal of Physical Anthropology. 104 (S25): 63–89. doi:10.1002/(SICI)1096-8644(1997)25+<63::AID-AJPA3>3.0.CO;2-8. {{cite journal}}: Check |url= value (help)
  20. ^ Bogin, Barry (1999). Patterns of human growth. Cambridge: Cambridge University Press. ISBN 0-521-56438-7. OCLC 39692257.[page needed]
  21. ^ Garrod, D. A. E., Buxton, L. H. D., Elliot-Smith, G., Bate, D.M. A. (1928). "Excavation of a Mousterian rock-shelter at Devil's Tower, Gibraltar". Journal of the Royal Anthropological Institute. 58: 33–113. JSTOR 4619528.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  22. ^ Keith, Arthur (1931). New discoveries relating to the antiquity of man. London: W. W. Norton & Company. p. 346. OCLC 3665578.
  23. ^ Ramirez Rozzi FV, Bermudez De Castro JM (April 2004). "Surprisingly rapid growth in Neanderthals". Nature. 428 (6986): 936–9. doi:10.1038/nature02428. PMID 15118725.
  24. ^ Macchiarelli R, Bondioli L, Debénath A, Mazurier A, Tournepiche JF, Birch W, Dean MC (December 2006). "How Neanderthal molar teeth grew". Nature. 444 (7120): 748–51. doi:10.1038/nature05314. PMID 17122777.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  25. ^ Guatelli-Steinberg, D., Reid, D.J., Bishop, T., and Larsen, C.S. (2005). "Anterior tooth growth periods in Neandertals were comparable to those of modern humans". Proceedings of the National Academy of Sciences. 102: 14197–14202.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  26. ^ Tafforeau P, Smith TM (February 2008). "Nondestructive imaging of hominoid dental microstructure using phase contrast X-ray synchrotron microtomography". Journal of Human Evolution. 54 (2): 272–8. doi:10.1016/j.jhevol.2007.09.018. PMID 18045654.
  27. ^ Smith TM, Toussaint M, Reid DJ, Olejniczak AJ, Hublin JJ (December 2007). "Rapid dental development in a Middle Paleolithic Belgian Neanderthal". Proceedings of the National Academy of Sciences. 104 (51): 20220–5. doi:10.1073/pnas.0707051104. PMC 2154412. PMID 18077342.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  28. ^ Smith TM, Tafforeau P, Reid DJ, Grün R, Eggins S, Boutakiout M, Hublin JJ (April 2007). "Earliest evidence of modern human life history in North African early Homo sapiens". Proceedings of the National Academy of Sciences. 104 (15): 6128–33. doi:10.1073/pnas.0700747104. PMC 1828706. PMID 17372199.{{cite journal}}: CS1 maint: multiple names: authors list (link)
Wikimedia Commons has media related to Homo neanderthalensis.
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