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Full-Text Articles in Geology
W(H)Ither Fossils? Studying Morphological Character Evolution In The Age Of Molecular Sequences, Elizabeth J. Hermsen, Jonathan R. Hendricks
W(H)Ither Fossils? Studying Morphological Character Evolution In The Age Of Molecular Sequences, Elizabeth J. Hermsen, Jonathan R. Hendricks
Jonathan R. Hendricks
A major challenge in the post-genomics era will be to integrate molecular sequence data from extant organisms with morphological data from fossil and extant taxa into a single, coherent picture of phylogenetic relationships; only then will these phylogenetic hypotheses be effectively applied to the study of morphological character evolution. At least two analytical approaches to solving this problem have been utilized: (1) simultaneous analysis of molecular sequence and morphological data with fossil taxa included as terminals in the analysis, and (2) the molecular scaffold approach, in which morphological data are analyzed over a molecular backbone (with constraints that force extant …
Biogeography And The Cambrian Radiation Of Arachnomorph Arthropods, Jonathan R. Hendricks, Bruce S. Lieberman
Biogeography And The Cambrian Radiation Of Arachnomorph Arthropods, Jonathan R. Hendricks, Bruce S. Lieberman
Jonathan R. Hendricks
Biogeographic patterns in primarily Cambrian arachnomorph taxa are investigated using a recently constructed phylogenetic hypothesis in order to explore the biogeographic context of the Cambrian radiation. A modified version of Brooks Parsimony Analysis is employed to elucidate patterns of vicariance and geodispersal in taxa from six regions (Laurentia, Baltica, Siberia, Australia, Africa and China). Well resolved vicariance and geodispersal trees are very similar and reconstruct Laurentia and China as sister areas. This close area relationship between Laurentia and China provides extensive evidence for congruent vicariance and range expansion in Cambrian arachnomorphs, while data from trilobites do not show this pattern. …