The Spanish Dryopithecus find indeed shows some similarities to orangutans, but its evolutionary position cannot yet be firmly established, assert Peter Andrews of the Natural History Museum in London and David Pilbeam of Harvard University in an accompanying commentary.
For example, the body proportions of the new Dryopithecus specimen closely resemble the proportions of African apes, Pilbeam argues.
The Harvard investigator also argues that the shape of Sivapithecus arm bones differs substantially from those of Dryopithecus, indicating no direct evolutionary relationship between these ancient apes.
Subsequently, Hispanopithecus was treated as a junior subjective synonym of Dryopithecus by many authors (Szalay and Delson, 1979; Moya Sola et al., 1990; Begun et al., 1990; Harrison, 1991; Andrews et al., 1996; Begun, 1992, 2002b), albeit with some exceptions (Golpe Posse, 1993; Cameron, 1997, 1999).
Although initial finds were assigned to Hispanopithecus laietanus, after the recovery of more abundant material, Dryopithecus crusafonti was distinguished (Begun, 1992); it was recently transferred to the genus Hispanopithecus by Moya-Sola et al.
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