- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography of Fossil Vertebrates, Society of Vertebrate Paleontology, Berkeley, CA, United States
The age (mortality) profiles of ungulate species in a fossil fauna are useful for reconstructing modes of death and of bone accumulation. Crown height measurements probably are the most practical means of obtaining age profiles in most samples. Reliable profiles will result when individual age is estimated from crown height using C. A. Spinage's mathematical model, and when the individual ages are grouped into broad age classes. One potential objection to the model is that it requires tedious calculation and there is a strong possibility of calculation error when many crown heights are involved. This problem may be circumvented by the use of an interactive BASIC program appended to this paper. The user supplies the raw crown heights in a fossil sample, together with estimates of initial unworn crown height, ages of dental shedding and eruption, and maximum possible individual age. The program then tabulates the number of individuals in successive 10%-of-potential-lifespan intervals.--Modified journal abstract.