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Cnidarian milestones in metazoan evolution
Ferdinando Boero1, Bernd Schierwater, Stefano Piraino
1*Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali DISTEBA, Università del Salento, I-73100 Lecce;
Integrative and Comparative Biology
|June 15, 2011
Summary
The common ancestor of cnidarians and bilaterians was complex, possessing features like a nervous system. Paedomorphosis in its descendants likely drove the evolution of animal diversity.
Area of Science:
- Evolutionary biology
- Developmental biology
- Zoology
Background:
- Cnidarians exhibit key traits of metazoan evolution.
- Many animal features emerged before the cnidarian-bilaterian split.
- The common ancestor (UrEumetazoa) was complex, with nerve cells.
Purpose of the Study:
- To investigate the evolutionary origins of animal body plans.
- To explore the role of paedomorphosis in animal diversification.
- To understand conserved molecular mechanisms in animal architecture.
Main Methods:
- Comparative analysis of cnidarian and bilaterian features.
- Review of molecular data and genetic determinants.
- Hypothesis testing of homologies and evolutionary relationships.
Main Results:
- A complex UrEumetazoa ancestor is inferred.
- Paedomorphic events are proposed as a driver of diversity.
- Conserved mechanisms likely govern body architecture.
Conclusions:
- Cnidarians offer insights into early animal evolution.
- Paedomorphosis played a significant role in shaping extant animal phyla.
- Molecular analyses are crucial for testing evolutionary hypotheses.
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