- GeoRef, Copyright 2004, American Geological Institute.
Analysis of brachiopod growth using bivariate graphs and growth axes demonstrates that individual species have distinct growth patterns. This fact is demonstrated by using data from 109 assemblages (6,373 specimens) of the Upper Silurian brachiopod Atrypoidea. Analysis of the width/length, height/length and height/width growth axes shows that each of the five species of Atrypoidea has unique points through which all the growth axes of assemblages belonging to that species pass. Further analysis shows that these discrete intersection points on each of the width/length, height/length and height/width graphs are related by a governing growth curve, a curve that is considered to be characteristic of the genus.--Modified journal abstract.