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Updated: Jul 28, 2026
08:57
Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin
Published on: August 14, 2018
Testing the vulnerability of the phylotypic stage: on modularity and evolutionary conservation
1Institute of Evolutionary and Ecological Sciences (EEW), Section Theoretical Evolutionary Biology, Leiden University, Kaiserstraat 63, 2311 GP Leiden, The Netherlands.
The Journal of Experimental Zoology
|August 2, 2001
Summary
The phylotypic stage in vertebrate development is highly vulnerable due to intense cellular interactions, explaining its conservation. This lack of modularity also influences Hox gene colinearity.
Area of Science:
- Developmental Biology
- Evolutionary Biology
- Teratology
Background:
- The phylotypic stage is when vertebrates share the most similarities.
- Previous hypotheses suggest this stage's conservation is due to high interactivity.
Purpose of the Study:
- To test hypotheses that the phylotypic stage is conserved because of intense interactivity.
- To determine if vulnerability during this stage is caused by interactivity or a specific vulnerable process.
Main Methods:
- Literature review of teratological data to assess stage-specific vulnerability.
- Analysis of induced anomalies to identify the root cause of vulnerability.
Main Results:
- The phylotypic stage exhibits significantly higher mortality when disturbed compared to other stages.
- Vulnerability during the phylotypic stage is primarily caused by the interactiveness and lack of modularity in developmental inductions.
Conclusions:
- The findings support the hypotheses of Sander and Raff regarding the conservation of the phylotypic stage.
- The absence of modularity in inductive interactions may also explain the conserved colinearity of Hox genes.
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