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Swin-PSAxialNet: An Efficient Multi-Organ Segmentation Technique
Published on: July 5, 2024
Sipunculans and segmentation.
Andreas Wanninger1, Alen Kristof, Nora Brinkmann
1University of Copenhagen; Department of Biology; Research Group for Comparative Zoology; Copenhagen, Denmark.
Communicative & Integrative Biology
|June 11, 2009
Summary
Segmentation in animals like Lophotrochozoa, Ecdysozoa, and Vertebrata is achieved through diverse developmental pathways. This plasticity fuels debate on whether segmentation evolved once or multiple times across animal lineages.
Area of Science:
- Developmental biology
- Evolutionary biology
- Comparative morphology
Background:
- Metameric body organization, or segmentation, is a fundamental characteristic of major animal lineages.
- Understanding the ontogenetic pathways of segmentation is crucial for evolutionary studies.
Purpose of the Study:
- To compare the diverse ontogenetic pathways of segmentation across Lophotrochozoa, Ecdysozoa, and Vertebrata.
- To investigate the role of developmental plasticity in the evolution of segmentation.
- To address the controversy regarding a single versus multiple origins of segmentation.
Main Methods:
- Comparative molecular analyses
- Developmental analyses
- Morphogenetic analyses
Main Results:
- Significant variation exists in the ontogenetic pathways establishing metameric organization across the three major segmented groups.
- Different mechanisms, including gene expression and tissue differentiation, operate at the segment level within a single organism.
- Evidence suggests segmentation loss may be more common than previously thought (e.g., sipunculans).
Conclusions:
- The developmental plasticity and evolutionary lability of segmentation support ongoing debate about its ancestral origins.
- Segmentation may have evolved independently multiple times rather than having a single common ancestor.
