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Peramorphic traits in the tokay gecko skull.
Juan D Daza1, Aurelia A Mapps1, Patrick J Lewis1
1Department of Biological Sciences, Sam Houston State University, 1900 Avenue I, Huntsville, Texas, 77341.
Journal of Morphology
|May 27, 2015
Summary
Geckos, often thought to only show paedomorphosis, actually develop peramorphic features like hyperossification near maturity. This study reveals new cranial characteristics in Gekko gecko, important for lizard evolution and taxonomy.
Area of Science:
- Herpetology
- Evolutionary Biology
- Developmental Biology
Background:
- Geckos are traditionally viewed as exhibiting paedomorphic traits, such as large eyes and less ossified skulls.
- Peramorphosis, a process of evolutionary extension of development, has not been significantly considered in gecko morphology.
Purpose of the Study:
- To document ontogenetic changes in cranial anatomy of Gekko gecko, focusing on peramorphic features near maturity.
- To identify cranial characteristics that strengthen with increasing size in geckos.
Main Methods:
- Studied cranial anatomy of Gekko gecko across different sizes, particularly near maturation.
- Compared findings with descriptions of other geckos to identify shared characteristics.
- Applied ACCTRAN and DELTRAN optimizations on a gekkotan molecular phylogeny to analyze character evolution.
Main Results:
- Identified 14 cranial characteristics in Gekko gecko that become more pronounced with size increase, indicating peramorphosis (hyperossification).
- These peramorphic features are most evident in later developmental stages, near maturation.
- Phylogenetic analysis suggests some of these traits are also present in closely related gecko species.
Conclusions:
- Peramorphosis plays a significant role in shaping gecko cranial morphology, contrary to previous assumptions.
- The identified peramorphic cranial features in Gekko gecko offer valuable characters for future phylogenetic and taxonomic research in lizards.
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