Homo erectus

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Homo erectus is an extinct hominid species that originated in East Africa about 1.8 to 1.9 million years ago. They survived until at least 800,000 years ago although some researchers put the date of their extinction as recently as 70 thousand years ago or less. Found in Africa, Asia, and possibly Europe, they were the most far-ranging hominid species to have existed before Homo sapiens and the first to come out of Africa.

This species is credited with significant advances in the use of stone tools including the earliest hand axes,[1] cleavers, and other large cutting tools. They used fire, ate meat, and hunted.[2] They were likely capable of speech, and evidence indicates they cared for their old and weak, just like modern humans do today.[3]

The species was discovered by Eugene DuboisWikipedia in Java, Indonesia, in 1891. The "Turkana Boy" or "Nariokotome Boy" fossil, discovered by Richard LeakeyWikipedia and A. Walker at Nariokotome, Kenya, in 1984, is the most complete early human skeleton ever discovered. It is approximately 1.6 million years old, the identification of which scientists disagree pending further evidence. Million and a half year-old footprints discovered in 2015 show conclusively that the gait of Homo erectus was well within the modern range of variability, meaning that modern human locomotion had already evolved 1.5 Ma.[4]

Homo erectus is likely a descendant as well as a contemporary of Homo habilis. Homo erectus is the direct ancestor of Homo sapiens, but only a specific subpopulation of H. erectus gave rise to modern humans, said same subpopulation being ancestral to Neanderthals and DenisovansWikipedia as well. Some researchers identify the early African material as Homo ergaster.

Physical characteristics[edit]

H. erectus demonstrates transitional features between australopithecines and modern humans. An individual could resemble a robust modern human at about 4'9" to 6'1" (1.45-1.85 m) in height and about 88 to 150 pounds (40-68 kg) with decreased sexual dimorphism compared to earlier hominids. It is likely that its growth rate was similar to that of great apes and that H. erectus was largely hairless. The increase in brain size from the australopithecines to approximately 900-930 cc nonetheless represents a significant statistical difference from that of modern humans, which is approximately 1350 cc, and H. erectus therefore had lower mental ability than do modern humans. However, later H. erectus specimens show cranial capacities well within the range of modern humans, if at the lower end, with the Peking Man fossils of ZhoukoudianWikipedia, China, showing cranial capacities of up to 1225 cc, with the average cranial capacity being 1015 cc.[5]

Features of the skull, jaw, and teeth were transitional between australopithecines and modern humans. There were noticeable differences between the neck and spine of this species and those of modern humans. The chest was more barrel-shaped rather than the funnel-shaped chest of australopithecines. The pelvis might have been narrower than that of modern humans, indicating a smaller infant brain size.

H. erectus possibly used fire, since the evidence for controlled fire dates from between 400,000 to 1,000,000 years ago.[6][7] However, evidence of three different species of tapeworms (Taenia saginata, T. asiatica and T. solium) in H. erectus fossils indicates that H. erectus was eating raw meat.[8] Katherine Zink and Daniel Lieberman conducted experiments with humans eating different foods (goat meat, yams, carrots, and beets) unprepared, pounded with a stone to soften it, sliced or cooked.[9][10] The researchers then compared the number of chews needed to eat the food. Participants couldn't break apart 3 gm chunks of raw goat meat after 40 chews, but could eat raw goat slices after an average of 31 chews. The overall conclusion was that H. erectus would need to chew their food less often (2.5 million fewer chews per year!) if they ate sliced goat with pounded roots. The hypothesized end result of this increased net caloric consumption was reduced need for large teeth and jaw muscles, which in turn allowed for larger brains and bodies.[9][10]

Creationists' viewpoints[edit]

Skulls of successive (or near-successive, depending on the source) human evolutionary ancestors
Brain size and tooth size in hominins

In order to maintain their claim that men appeared suddenly and without prior evolutionary history, it is necessary for creationists to identify early hominid fossils as being either "fully human" or "fully ape."[11] However, there is a lack of agreement among creationists as to which fossils to call ape and which to call human.[12] An Answers in Genesis (AIG) article notes that H. erectus was traditionally placed with apes, however more recently tends to be placed with humans. [13] It is also interesting to note that the author admits he disagrees with creationist Marvin Lubenow about where to place Homo habilis.

To demonstrate that H. erectus is fully human, the website "Darwinism Refuted" claims, "There is no difference between the postcranial skeleton of modern man and that of Homo erectus." [14] In addition to admitting that there are differences in the skulls, this statement ignores differences such as those in the neck, spine, pelvis, feet, growth rate, and others noted by paleontologists. As further evidence that H. erectus was human, the website presents a recent photograph of a guy with a sloping forehead and additionally a supportive quote from Lubenow, a young Earth creationist per CreationWiki.

The author of the above-mentioned AIG article notes one G. I. Beasley's speculation that apparent differences between H. erectus fossils and modern human skeletons could be caused by "prolongation of skeletal maturation and greater longevity potential; environmental; and dietary/pathological pressures within a post-Deluge framework." The author goes on to proclaim, "Beasley's paper is a land-mark in creationist research on this subject, and every Christian should possess a copy with which to question materialist-minded educators." Beasley's essential "research" referenced is an essay titled "A possible creationist interpretation of archaic fossil human remains" that appeared in the Journal of Creation in 1992. Greg Beasley is an engineering analyst with Sydney, Australia's, CityRail.[15]

The AIG article poses the question of how, given that H. erectus was supposed to have evolved into H. sapiens, do anthropologists "reconcile the presence in Australia of both modern sapiens types and erectus types all within the last 35,000 years?" In fact, although the Kow Swamp people that were mentioned do bear a superficial resemblance to H. erectus, it is not the scientific consensus that this indicates the species existed in Australia at this late date.[16]

The AIG article uses the gradual evolution from H. erectus to H. sapiens as evidence that they are the same species. Additionally both this article and the above-mentioned "Darwinism Refuted" webpage refer to the minority opinion of paleoanthropologist Milford Wolpoff that the species H. erectus is redundant and that for taxonomic reasons it should be sunk into H. sapiens. Both of these arguments fail to recognize the clear differences between the species.

AIG further makes the claim that the creationist view would eliminate any perceived confusion regarding the species making up the genus Homo. The author notes, "On the other hand, if creationists are right in believing that earth has only a short history (measured in millennia, rather than millions of years), then there would be no argument — all forms of Homo (except the phantom-like H. habilis), would form just a single contemporary species." This logic demonstrates the creationist tendency to seek evidence that supports the conclusion rather than to let the evidence lead to it.

In another AIG article we find the creationist explanation for the existence of H. erectus fossils. Therein the author reasons that at the time of the Tower of Babel, all humans must have looked like H. erectus, since they were the first hominid to spread out over the Earth and the Bible indicates that humans did not do so until after the flood. The article also claims, "Aside from the skull, Homo erectus skeletons are virtually indistinguishable from modern humans, so the evidence indicates they are human."[17] The fallacies involved in these arguments include the observation that H. erectus could not possibly have had the culture described in the relevant Bible passages. For a more in-depth examination of the fallacies involved in this article, see Brayton (2008).[18]

See also[edit]

External links[edit]

References[edit]

  1. Homo erectus
  2. Homo erectus was pretty smart already judging by evidence that fire had been discovered over 1.6 million years ago
  3. Lordkipanidze, David (2017). "The History of Early Homo". In Tibayrenc, Michel. On Human Nature: Biology, Psychology, Ethics, Politics, and Religion. Academic Press. pp. 45–54. ISBN 978-0-12-420190-3. 
  4. Homo erectus footprints hint at ancient hunting party
  5. Peking Man
  6. Francesco Berna, Paul Goldberg, Liora Kolska Horwitz, James Brink, Sharon Holt, Marion Bamford, and Michael Chazan. Microstratigraphic evidence of in situ fire in the Acheulean strata of Wonderwerk Cave, Northern Cape province, South Africa. Proceedings of the National Academy of Sciences, April 2, 2012 DOI: 10.1073/pnas.1117620109.
  7. Miller, Kenneth (May 2013). "Archaeologists Find Earliest Evidence of Humans Cooking With Fire". Discover.
  8. [Dragon Bone Hill: An Ice-Age Saga of Homo erectus by Noel t. Boaz & Russell L. Ciochon (2004) Oxford University Press. ISBN 0195152913.
  9. 9.0 9.1 H. erectus cut, chewed way through evolution: Less energy needed to eat sliced raw meat led to smaller teeth, jaw by Bruce Bower (1:00pm, March 9, 2016) Science News.
  10. 10.0 10.1 [Impact of meat and Lower Palaeolithic food processing techniques on chewing in humans] by Katherine D. Zink & Daniel E. Lieberman. Nature. Published online March 9, 2016. doi: 10.1038/nature16990.
  11. Bowden, Malcolm (1988). "Homo erectus—A Fabricated Class of 'Ape-Men'."
  12. Comparison of all skulls. talk.origins. Oct. 28, 2008.
  13. Mehlert, A. W. (Apr. 1994). Homo erectus 'to' modern man: evolution or human variability?.
  14. The Origin of Man: Homo erectus. Darwinism Refuted.
  15. Darwin Doubters of the Twentieth & Twenty First Century.
  16. Kow Swamp. Peter Brown's Australian & Asian Palaeoanthropology.
  17. Lucy Was Buried First: Babel Helps Explain the Sequence of Ape and Human Fossils. Answers in Genesis. 2009.
  18. Brayton, Ed (Aug. 22, 2008). The Sadness of Kurt Wise. ScienceBlogs