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Updated: Jul 19, 2026
12:59
Three and Four-Dimensional Visualization and Analysis Approaches to Study Vertebrate Axial Elongation and Segmentation
Published on: February 28, 2021
Vertebrate head development: segmentation, novelties, and homology
Lennart Olsson1, Rolf Ericsson, Robert Cerny
1Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-Schiller-Universität, D-07743 Jena, Germany. Lennart.Olsson@uni-jena.de
Theory in Biosciences = Theorie in Den Biowissenschaften
|October 19, 2006
Summary
Vertebrate head development reveals neural crest cells pattern cranial muscles and jaw formation. Evolutionary developmental biology clarifies jaw origins and homology through gene expression and developmental insights.
Area of Science:
- Developmental Biology
- Evolutionary Biology
- Craniofacial Development
- Genetics
Background:
- Classical segmentalist views of vertebrate head development are being revised.
- The head is now understood as patterned by distinct mechanisms and tissues, unlike the trunk.
- Neural crest cells play a crucial role in head patterning, influencing mesodermal derivatives.
Purpose of the Study:
- To explore the distinct patterning mechanisms in vertebrate head development compared to the trunk.
- To investigate the role of neural crest cells in cranial morphogenesis and jaw development.
- To apply evolutionary developmental biology principles to understand craniofacial homology.
Main Methods:
- Analysis of gene expression patterns, particularly Dlx genes, in craniofacial development.
- Investigating the origins and contributions of neural crest cells and pharyngeal endoderm.
- Utilizing genetic manipulation (e.g., gene knockouts) to study developmental processes.
Main Results:
- Neural crest cells carry pattern information for cranial muscle and connective tissue development.
- Jaw development involves exaptation and heterotopic gene expression shifts, with Dlx genes patterning jaws.
- Knocking out Dlx 5 and 6 results in homeotic transformation of the lower jaw into an upper jaw.
- Both upper and lower jaw cartilages originate from a common mandibular anlage.
Conclusions:
- Vertebrate head development is orchestrated by unique mechanisms involving neural crest and pharyngeal endoderm.
- Jaw evolution is linked to regulatory gene shifts, with Dlx genes being key patterning factors.
- Evolutionary developmental biology enhances understanding of biological characters and homology.
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