An Ossified Meckel's Cartilage in Two Cretaceous Mammals and Origin of the Mammalian Middle Ear
Yuanqing Wang,1*
Yaoming Hu,123
Jin Meng,2*
Chuankui Li1
An ossified Meckel's cartilage has been recovered from
two early Cretaceous mammals from China. This element is similar to Meckel's cartilage in prenatal and some postnatal extant mammals and
indicates the relationship of Meckel's cartilage with the middle ear
in early mammals. The evidence shows that brain expansion may not be
the initial factor that caused the separation of postdentary bones from
the dentary as middle ear ossicles during mammalian evolution. The
failure of the dentary to seize reduced postdentary elements during
ontogeny of early mammals is postulated as an alternative mechanism for
the separation. Modifications of both feeding and hearing apparatuses
in early mammals may have led to the development of the definitive
mammalian middle ear.
1 Institute of Vertebrate Paleontology and
Paleoanthropology (IVPP), Chinese Academy of Sciences, Post Office Box
643, Beijing, 100044, China.
2 Division of
Paleontology, American Museum of Natural History (AMNH), Central Park
West at 79th Street, New York, NY 10024, USA.
3 Biology Program (Ecology, Evolutionary Biology,
and Behavior), Graduate School and City College, City University of New
York, NY 10016-4309, USA.
*
To whom correspondence should be addressed. E-mail:
wang.yuanqing{at}pa.ivpp.ac.cn (Y.W.); jmeng{at}amnh.org
(J.M.)
