Bioscience Hypotheses(2008)1,127-137
Cranio-dental evidence of a hominin-likehyper-masticatory apparatus in
Oreopithecusbambolii. Was the swamp ape a human ancestor?
Marcel Francis Williams
Abstract
The phylogeny of Oreopithecus bambolii has been controversial since
Johannes Hurzeler first argued that the Late Miocene (Tortonian)
primate was a fossil hominin. While most paleontologist currently
exclude Oreopithecus from human ancestry, recent postcranial evidence
of hominin-like bipedalism and power precision grips in Oreopithecus
has rekindled interest in the fossil Italian hominoid.
In this study, a comparative review of hominoid cranio-dental
morphology indicates that Oreopithecus possessed a suite of
hominin-like characteristics that were apparently functionally related
to powerful folivorous mastication. Since the oreopithecine dentition
exhibited exceptional adaptations for folivory relative to most other
extant and extinct hominoids, the accessory development of a
hominin-like hyper-masticatory cranio-mandibular apparatus to further
enhance plant comminution and digestibility is not surprising.
However, the combination of hominin-like locomotive, manual, and
masticatory functional attributes appears to substantiate Hurzeler's
designation of O. bambolii as a Late Miocene hominin. Additionally, an
extensive compilation of hominoid cranio-dental and postcranial
characteristics strongly sup****ts a close phylogenetic relation****p
between Oreopithecus and the earliest African hominins Sahelanthropus
and Australopithecus.
The wetland paleoecology of the Tortonian island of
Tuscany=EF=BF=BD"Sardin=
ia
suggests that Oreopithecus was a specialized semiaquatic folivore who
apparently waded bipedally into freshwater swamps to feed on aquatic
plants. However, the extensive wear on the oreopithecine canines and
incisors along with their manual precision grips may indicate that
freshwater invertebrates were also included in their diets. Such
specialized aquatic feeding behavior by these ancient Italian swamp
apes seems to sup****t Alister Hardy's hypothesis that human bipedalism
and power precision grips were inherited from Late Miocene hominin
ancestors who originally utilized such functional attributes for
aquatic foraging in shallow water environments. Additionally, the
remarkably hominin-like cranio-dental morphology of O. bambolii
suggests that modern omnivorous humans probably inherited a
significant number of their cranio-dental characteristics from these
highly specialized aquatic plant eating hominins.
2008ElsevierLtd.All rights reserved.
doi:10.1016/j.bihy.2008.04.001
|
