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Morphological integration versus ecological plasticity in the avian pelvic limb skeleton
Alexander Stoessel1, Brandon M Kilbourne, Martin S Fischer
1Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität Jena, Jena, Germany. alexander_stoessel@eva.mpg.de
Journal of Morphology
|January 8, 2013
Summary
Avian hindlimb morphology is primarily shaped by body mass, with leg length variations mainly from the tibiotarsus and tarsometatarsus. Not all limb elements are integrated, showing diverse evolutionary pathways.
Area of Science:
- Comparative anatomy
- Evolutionary biology
- Biomechanics
Background:
- Understanding avian pelvic limb skeletal variation is key to deciphering evolutionary processes.
- Morphological traits are influenced by body mass, ecology, phylogeny, and integration.
Purpose of the Study:
- To investigate avian hindlimb skeletal morphology variation.
- To examine the influence of body mass, ecology, and phylogeny on hindlimb structure.
- To test for morphological integration within the avian hindlimb.
Main Methods:
- Measurement of length and width variables in 236 avian species.
- Analysis of scaling relationships with body mass.
- Principal component analysis, multiple regressions, and partial correlation analysis.
Main Results:
- Body mass is the primary driver of avian skeletal length variation.
- Tibiotarsal and tarsometatarsal lengths show strong integration; femur and toe lengths vary more.
- Ecological adaptations are complex due to hindlimb multifunctionality; phylogeny significantly constrains morphology.
Conclusions:
- Morphological integration of all limb elements is not essential for avian hindlimb design.
- Variation in avian hindlimb morphology is influenced by body mass, phylogeny, and functional constraints.
- Avian hindlimbs exhibit evolvability, adapting to diverse functions through varied morphological strategies.
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