Related Experiment Video
Updated: Jun 20, 2026
12:09
Protocol for Human Blastoids Modeling Blastocyst Development and Implantation
Published on: August 10, 2022
A developmental perspective: changes in the position of the blastopore during bilaterian evolution
Mark Q Martindale1, Andreas Hejnol
1Kewalo Marine Laboratory, PBRC, University of Hawaii, 41 Ahui Street, Honolulu, HI, 96813, USA. mqmartin@hawaii.edu
Developmental Cell
|August 19, 2009
Summary
Recent phylogenetic and molecular developmental studies offer new insights into animal evolution. This review presents a hypothesis on the developmental scenarios that led to complex multicellular animals from a radially organized ancestor.
Area of Science:
- Evolutionary developmental biology
- Animal phylogeny
Background:
- Phylogenetic relationships among animals are becoming clearer.
- Molecular developmental studies are expanding to diverse organisms.
- This progress allows reevaluation of hypotheses on animal body plan evolution.
Purpose of the Study:
- To review recent studies on animal evolution.
- To shed light on the transition from radial symmetry to bilateral symmetry.
- To propose a hypothesis for the evolution of complex multicellular animals.
Main Methods:
- Review of recent phylogenetic studies.
- Analysis of molecular developmental data.
- Integration of findings to form a hypothesis.
Main Results:
- New insights into the evolution of developmental programs.
- Reevaluation of hypotheses on the evolution of animal body plans.
- An integrative hypothesis for the evolution of complex multicellular animals.
Conclusions:
- The transition from radial ancestors to the Urbilaterian involved significant developmental changes.
- Plausible developmental scenarios can explain the evolution of animal complexity.
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