Comparative Anatomy, Evolution, and Homologies of Tetrapod Hindlimb Muscles, Comparison with Forelimb Muscles, and Deconstruction of the Forelimb‐Hindlimb Serial Homology Hypothesis

This study presents the first detailed analysis of the evolution and homologies of all hindlimb muscles in representatives of each major tetrapod group and proposes a unifying nomenclature for these muscles. These data are compared with information obtained previously about the forelimb muscles of tetrapods and the muscles of other gnathostomes in order to address one of the most central and enigmatic questions in evolutionary and comparative anatomy: why are the pelvic and pectoral appendages of gnathostomes generally so similar to each other? An integrative analysis of the new myological data, combined with a review of recent paleontological, developmental, and genetic works and of older studies, does not support serial homology between the structures of these appendages. For instance, many of the strikingly similar forelimb and hindlimb muscles found in each major extant tetrapod taxon were acquired at different geological times and/or have different embryonic origins. These similar muscles are not serial homologues, but the result of evolutionary parallelism/convergence due to a complex interplay of ontogenetic, functional, topological, and phylogenetic constraints/factors. Anat Rec, 2014. © 2014 Wiley Periodicals, Inc.

Source: The Anatomical Record Part B: The New Anatomist - April 1, 2014 Category: Anatomy Authors: Rui Diogo, Julia Molnar Tags: Full Length Article Source Type: research