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Repeated evolution of digital adhesion in geckos: a reply to Harrington and Reeder
T Gamble1,2, E Greenbaum3, T R Jackman4
1Department of Biological Sciences, Marquette University, Milwaukee, WI, USA.
Journal of Evolutionary Biology
|April 24, 2017
Summary
Geckos evolved adhesive toepads multiple times. A recent study
Area of Science:
- Evolutionary biology
- Comparative genomics
- Herpetology
Background:
- Gecko adhesive toepads have evolved multiple times.
- Morphological studies support multiple origins of gecko toepads.
- Previous phylogenetic analyses indicated repeated evolution of gecko toepads.
Purpose of the Study:
- To re-evaluate the evolutionary history of gecko adhesive toepads.
- To address discrepancies in phylogenetic analyses of gecko toepad evolution.
- To investigate the impact of morphological data on ancestral state reconstruction.
Main Methods:
- Phylogenetic comparative analysis.
- Ancestral state reconstruction using evolutionary models.
- Incorporation of morphological evidence into phylogenetic models.
Main Results:
- The multiple origins hypothesis for gecko toepads is supported by morphological data.
- Biologically unrealistic models can lead to erroneous evolutionary conclusions.
- Previous reanalysis failed to adequately incorporate morphological evidence.
Conclusions:
- Gecko adhesive toepads have evolved repeatedly throughout their evolutionary history.
- Morphological data are crucial for accurate ancestral state reconstruction in evolutionary studies.
- The methodology used in recent reanalyses may have led to inaccurate conclusions regarding gecko evolution.
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