The Evolution of Man

[BorneanTiger]

(07-07-2020, 09:48 PM)BorneanTiger Wrote: Modern humans are of the species Homo sapiens, which is believed to have derived from Homo erectus anywhere from 300–800 thousand years ago. Homo erectus or Homo ergaster represent the second earliest known specimens of the human race, dating as far back as approximately 2 million years ago, with Homo habilis (which is considered to have lived 2.3–1.65 million years ago, and might be the same as Homo rudolfensis and Homo gautengensis) being the first. Though Homo habilis is not confirmed to have had obligate bipedalism (like australopithecines and unlike Homo erectus / ergaster), the cranium of KNM-ER 1813 (from Koobi Fora in Kenya, dated to approximately 1.9 million years ago, in the early years of Homo ergaster / erectus) is too similar to the cranium of a human being to be belong to an ape, in my opinion:

Cast of the skull KNM-ER 1813 at Göteborgs Naturhistoriska Museum, Göteborg, Västra Götaland County, Sweden, by Gunnar Creutz (10th of November 2019), versions 8563, 8564 and 8807:

*This image is copyright of its original author

*This image is copyright of its original author

*This image is copyright of its original author

Cast of the skull KNM-ER 1813 by The Smithsonian: https://humanorigins.si.edu/evidence/hum...mo-habilis, https://humanorigins.si.edu/evidence/hum...nm-er-1813

*This image is copyright of its original author

The skeleton of AL 288-1 or Lucy (Australopithecus afarensis), cast from Museum National d'Histoire Naturelle, Paris, by User 120 (27th of March 2007):

*This image is copyright of its original author

Whereas Homo sapiens is considered to have originated in Africa, fossils of Homo erectus / ergaster have been found in Eurasia and Africa, treating Homo erectus and Homo ergaster as belonging to the same species. Below is the skeleton of the "Turkana boy" of Kenya, who was of the species Homo erectus / ergaster, which shows that this race was bipedal like modern humans: https://evolution-outreach.biomedcentral...010-0247-8

*This image is copyright of its original author

Like I said there, Homo habilis might be the same species as Homo rudolfensis or Homo gautengensis, but we are not sure. Several specimens with insecure species' identification were assigned to H. habilis, leading to arguments for splitting, namely into H. rudolfensis and H. gautengensis, of which only the former has received wide support.

1) Here is a reconstruction of the skull KNM-ER-1470 (which had been assigned to H. rudolfensis), displayed at Museum of Man, San Diego, by Durova (4th of December, 2007):
   

A cast of the skull at Göteborgs Naturhistoriska Museum, Göteborg, Västra Götaland County, Sweden, by Gunnar Creutz (10th of November, 2019):
   

2) On its own, KNM-ER-1470 may not look extraordinary, but if you put it next to KNM-ER 1813 (which is depicted in my post above, and was assigned to both H. habilis and H. erectus) then it becomes more interesting. Note that they were both found in Koobi Fora, Kenya, and dated to approximately 2 mya (million years ago): https://science.sciencemag.org/content/198/4312/13, http://mr.crossref.org/iPage?doi=10.1144...492010-188

Conty (26th of July, 2011):
   

Gunnar Creutz (10th of November, 2019):
   

KNM-ER-1470 is visibly bigger than KNM-ER 1813. Is it because they belong to different species, or is this a mere case of sexual dimorphism being prominent in the same species, in which case they could be treated as belonging to a male and female from the species H. habilis? Not only were fossils which were classified under H. habilis contemporaneous with those classified under H. rudolfensis, but also those classified under H. erectus / ergaster, and Paranthropus bosei (also Zinjanthropus bosei or Australopithecus bosei).

3) Now for fragments of skulls that were assigned to H. gautengensis, respectively STW-53 (which was discovered in Swartkrans, South Africa, and dated to approximately 1.8–1.5 mya) and SK-847 (found in Krugersdrop, Transvaal, South Africa, and dated to approximately 1.78–1.43 mya): http://www.isita-org.com/jass/contents/2...011933.pdf, https://www.nature.com/articles/265310a0, https://humanorigins.si.edu/evidence/hum...ils/sk-847, https://orsa.sitehost.iu.edu/Sk847_details.html, https://pubmed.ncbi.nlm.nih.gov/8296872/

STW-53, by Rhuangagabi (2nd of July, 2015):
   

SK-847 at the David H. Koch Hall of Human Origins at the Smithsonian Natural History Museum, 1st of January 1980, by Ryan Somma:
   

Note that SK-847 is part of a larger collection of skulls, credit: Ryan Somma
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