Download or read book Palaeobiology of Middle Paleozoic Marine Brachiopods written by Rituparna Bose and published by Springer Science & Business Media. This book was released on 2013-05-14 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fossil species appear to persist morphologically unchanged for long intervals of geologic time, punctuated by short bursts of rapid change as explained by the Ecological Evolutionary Units (EEUs). Here, morphological variation in Paleozoic atrypide morphology at the subfamily level (Atrypinae and Variatrypinae) from the Silurian and Devonian time intervals in the third Paleozoic EEU (~444-359 my) were investigated using relatively new techniques of quantitative modeling. The study explains how a group of closely related taxa in atrypide subfamilies exhibit morphological conservation through time in P3 EEU within the Eastern North America region.