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Published on: June 3, 2013
Defining sameness: historical, biological, and generative homology
1Krasnow Institute for Advanced Study and Department of Psychology, George Mason University, Fairfax, Virginia 22030, USA. ABButler@gmu.edu
Summary
New terms, syngeny (same genesis) and allogeny (different genesis), are proposed to clarify homology in developmental biology. These terms distinguish characters based on their generative pathways, aiding comparative studies.
Area of Science:
- Evolutionary developmental biology
- Comparative genomics
- Phylogenetics
Background:
- Homology is debated across phylogenetics, character evolution, and generative pathways.
- Phylogenetic homology emphasizes common ancestry, while biological homology focuses on character evolution.
- Similar characters can arise from different generative pathways, complicating traditional homology definitions.
Purpose of the Study:
- To introduce new descriptive terms for comparative developmental biology.
- To differentiate between characters arising from identical versus distinct generative pathways.
- To enhance the precision of homology assessment in evolutionary studies.
Main Methods:
- Conceptual framework development for homology.
- Introduction of novel terminology: syngeny and allogeny.
- Integration of new terms with existing phylogenetic and biological homology concepts.
Main Results:
- Syngeny describes characters sharing the same generative pathway.
- Allogeny describes characters with different generative pathways.
- These terms provide a nuanced understanding of character similarity and origin.
Conclusions:
- Syngeny and allogeny offer a more precise vocabulary for comparative developmental biology.
- The proposed terms facilitate clearer distinctions in studies of character evolution.
- These terms complement existing concepts of historical and biological homology.
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