At the microstructural level, bone is hypothesized to record aspects of the mechanical adaptation and life history of vertebrates. It follows that information with bearing upon the biology and behavior of fossil taxa is potentially encoded therein. However, before interpretations of microstructure in extinct species are possible, the extent of variability that exists in living groups, and the relationship of this variability to biological and behavioral features, must be understood.
Here I report on variation in three bone microstructural features: primary bone tissue types, intracortical remodeling, and collagen fiber orientation. These were examined in midshaft cortices from the femur, humerus, tibia, radius and ulna in a sample of extant strepsirhine, tarsiid and platyrrhine primates. Employing conventional and polarized light microscopy techniques, the aims were to qualitatively and quantitatively describe the relationship of these microstructural features to several mechanical adaptation and life history characteristics of species: developmental patterns, body size, growth rate, positional behavior, and phylogenetic status.
This study has shown that variation in the three microstructural variables exists among primates, that this variation is often non-randomly distributed, and that it is partly explicable via a consideration of development, growth rate, body size, positional behavior and phylogeny. Primary tissue types vary with body size, growth rate and, concurrently, phylogenetic status as well as, potentially, positional behavior. Percent intracortical remodeling varies principally as a function of body size, with a subsidiary relationship to positional behavior. Finally, contrary to predictions based on previous descriptions in the literature, collagen fiber orientation shows little relationship with positional behavior and inferred diversity in mechanical loads. Rather, the limited variation that does exist correlates best with primary tissue type.
The study also clearly demonstrates that much of the diversity in the sample is not explained by the factors examined here. This suggests that more work must to be done to illuminate the variables impacting upon bones as they grow. It also serves as a warning that, at present, micro-morphological features must be employed only with a full understanding of their current limitations—in addition to their exciting potential—as tools in the study of fossil taxa.
|Adviser||Timothy G. Bromage|
|School||CITY UNIVERSITY OF NEW YORK|
|Subjects||Morphology; Physical anthropology|
About ProQuest Dissertations & Theses
With nearly 4 million records, the ProQuest Dissertations & Theses (PQDT) Global database is the most comprehensive collection of dissertations and theses in the world. It is the database of record for graduate research.
PQDT Global combines content from a range of the world's premier universities - from the Ivy League to the Russell Group. Of the nearly 4 million graduate works included in the database, ProQuest offers more than 2.5 million in full text formats. Of those, over 1.7 million are available in PDF format. More than 90,000 dissertations and theses are added to the database each year.