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Evo-devo: variations on ancestral themes.

E M De Robertis¹

¹Howard Hughes Medical Institute and Department of Biological Chemistry, University of California, Los Angeles, CA 90095-1662, USA. ederobertis@mednet.ucla.edu

|February 5, 2008

Summary

This summary is machine-generated.

Most animals share a common ancestor, Urbilateria, with established body plan genes. Evolution involved significant gene loss in various animal groups, impacting developmental genetics and body plan diversity.

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Area of Science:

Evolutionary developmental biology
Comparative genomics
Animal evolution

Background:

Most animals trace their origins to a common ancestor, Urbilateria.
Urbilateria possessed the foundational genetic networks for body plan development.
Comparative genomics reveals substantial gene loss across animal phyla during evolution.

Purpose of the Study:

To reconstruct the ancestral developmental genetic toolkit of Urbilateria.
To understand the role of gene loss in animal body plan evolution.
To investigate the impact of developmental constraints on evolutionary trajectories.

Main Methods:

Comparative genomic analysis of animal phyla.
Phylogenetic reconstruction of ancestral gene content.
Bioinformatic analysis of developmental gene networks.

Main Results:

Identification of conserved and lost genes in bilaterian ancestors.
Evidence for extensive gene loss from the Urbilaterian gene repertoire.
Correlation between gene loss and diversification of animal body plans.

Conclusions:

Gene loss is a significant factor shaping animal evolution.
Developmental constraints influenced the evolutionary pathways of animal body plans.
Reconstructing the Urbilaterian toolkit is crucial for understanding animal origins.