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Human Uniqueness Compared to "Great Apes": 
No Difference
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Osteoarthritis is the common term used for degenerative joint disease and is described in aging humans. The disease is characterized by the progressive erosion of articular cartilage. In the great majority, osteoarthritis appears insidiously without an apparent cause as an age related phenomenon. Although osteoarthritis is not exclusively a wear-and-tear process, mechanical stresses on the joint do play a role in its development. Biochemical changes in the content of the cartilage allow it to wear away, exposing underlying bone, which causes friction and inflammation. Osteoarthritis also affects gorillas, chimpanzees, gibbons, and baboons affecting the knee joint most often (Pritzker 1994 etc.). There are likely no differences between humans and great apes with respect to Osteoarthritis.


  1. Modern-day environmental factors in the pathogenesis of osteoarthritis, Berenbaum, Francis, Wallace Ian J., Lieberman Daniel E., and Felson David T. , Nature Reviews, 2018/09/12, (2018)
  2. Ancient selection for derived alleles at a GDF5 enhancer influencing human growth and osteoarthritis risk., Capellini, Terence D., Chen Hao, Cao Jiaxue, Doxey Andrew C., Kiapour Ata M., Schoor Michael, and Kingsley David M. , Nat Genet, 2017 Jul 03, (2017)
  3. Knee osteoarthritis has doubled in prevalence since the mid-20th century, Wallace, Ian J., Worthington Steven, Felson David T., Jurmain Robert D., Wren Kimberly T., Maijanen Heli, Woods Robert J., and Lieberman Daniel E. , PNAS, 2017/08/14, (2017)