diffundit® Open Conference Systems Platform, XIX Congreso de la SEAF / 23-26 junio 2015

Por defecto: 
Growing Up Ape
Debra Bolter

Última modificación: 12-05-2015

Resumen


Objective: Apes provide a valuable counterpoint for comparison with the earliest hominins in dental and skeletal growth, two components of life history.   This study examines the relationship between dental and skeletal growth in wild and captive chimpanzees, and compares with other apes, to identify patterns of what constitutes an “ape-like” growth, development and life history.

Material and Methods: Wild skeletal sample includes Pan troglodytes (33 immature, 15 adult), 10 of known age, and 10 known age captives. Immatures were categorized into 4 age classes by molar eruption sequences, and assessed for bone fusions in relation to dental development.  Adult (5th class) was determined by proximal humeral fusion.

Results: By age class 4 (M3 newly erupted) sub-adult P. troglodytes have all permanent teeth but incomplete body maturity.  For example, sub-adults have completed fusion at elbow and hip joints and partial fusion of the ankle, but are unfused at knee and shoulder epiphyses.  Similarly-aged captives display an accelerated maturity in eruptions and fusions, and earlier adulthood.

Conclusion: Teeth fully erupt before skeletal elements fuse in chimpanzees, and both are influenced by environmental conditions. Additional body system data on Pan paniscus, Gorilla, Pongo and Hylobates suggest a sexually dimorphic pattern in that male apes reach adult muscle mass and body weight after all teeth are erupted and long bones fused, later than the pattern found in female conspecifics.  These “ape-like” timings and patterns of body system maturity provide an additional perspective beyond Homo sapiens when reconstructing life stages in early fossil hominins.


 


Palabras clave


life history; ape; dentition; skeleton

Debe registrarse a la conferencia para ver los trabajos