Publications by authors named "Sakdapong Chavanaves"

3 Publications

  • Page 1 of 1

Earliest Known Hominin Calcar Femorale in Orrorin tugenensis Provides Further Internal Anatomical Evidence for Origin of Human Bipedal Locomotion.

Anat Rec (Hoboken) 2018 11 19;301(11):1834-1839. Epub 2018 Oct 19.

Laboratory for the Comparative Study of Morphology, Mechanics and Molecules, Department of Kinesiology, Pennsylvania State University, State College, Pennsylvania, 16801.

The calcar femorale (CF), a plate of dense bone internal to the lesser trochanter, is visible on computed tomographic images of the 6 million-year-old femoral fragment BAR 1003'00 (from the taxon Orrorin tugenensis), among the oldest specimens relevant to reconstructing the evolution of human bipedal locomotion. A strongly expressed CF has been used previously as an indicator of bipedality. If true, then there should be a quantifiable difference in the CF among hominoids. Absolute and normalized CF lengths were measured from computed tomographic images at five anatomical locations along the proximal portion of BAR 1003'00 in addition to samples of nine H. sapiens and ten P. troglodytes femora. The span of the CF superiorly to inferiorly within the proximal femur was measured by counting the number of cross-sections on which the CF occurred. A Bayesian approach was used to classify the BAR 1003'00 sample based on normalized lengths. The P. troglodytes femora were more variable both in the occurrence of the trait and, where present, its span in the proximal femur. The H. sapiens sample exhibited CF lengths that were consistently larger at each location than the P. troglodytes in absolute terms, but the normalized lengths overlap substantially. The Bayesian posterior probability test classifies the CF of BAR 1003'00 with H. sapiens. The BAR 1003'00's calcar femorale has a strong anatomical similarity to the H. sapiens sample, supporting the conclusion that O. tugenensis is an early bipedal hominin. Anat Rec, 301:1834-1839, 2018. © 2018 Wiley Periodicals, Inc.
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http://dx.doi.org/10.1002/ar.23939DOI Listing
November 2018

Reply to Westaway et al.: Mandibular misrepresentations fail to support the invalid species Homo floresiensis.

Proc Natl Acad Sci U S A 2015 Feb 6;112(7):E606. Epub 2015 Feb 6.

Kenneth J. Hsü Center for Integrated Hydrological Circuits Development, National Institutes of Earth Sciences, Beijing 100871, China.

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http://dx.doi.org/10.1073/pnas.1422176112DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4343134PMC
February 2015

Evolved developmental homeostasis disturbed in LB1 from Flores, Indonesia, denotes Down syndrome and not diagnostic traits of the invalid species Homo floresiensis.

Proc Natl Acad Sci U S A 2014 Aug 4;111(33):11967-72. Epub 2014 Aug 4.

Kenneth J. Hsü Center for Integrated Hydrological Circuits Development, National Institutes of Earth Sciences, Beijing 100871, China

Human skeletons from Liang Bua Cave, Flores, Indonesia, are coeval with only Homo sapiens populations worldwide and no other previously known hominins. We report here for the first time to our knowledge the occipitofrontal circumference of specimen LB1. This datum makes it possible to link the 430-mL endocranial volume of LB1 reported by us previously, later confirmed independently by other investigators, not only with other human skeletal samples past and present but also with a large body of clinical data routinely collected on patients with developmental disorders. Our analyses show that the brain size of LB1 is in the range predicted for an individual with Down syndrome (DS) in a normal small-bodied population from the geographic region that includes Flores. Among additional diagnostic signs of DS and other skeletal dysplasiae are abnormally short femora combined with disproportionate flat feet. Liang Bua Cave femora, known only for LB1, match interlimb proportions for DS. Predictions based on corrected LB1 femur lengths show a stature normal for other H. sapiens populations in the region.
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http://dx.doi.org/10.1073/pnas.1407382111DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4143021PMC
August 2014
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