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Published on: February 28, 2021
Saltational evolution of trunk segment number in centipedes
Alessandro Minelli1, Amazonas Chagas-Júnior, Gregory D Edgecombe
1Dipartimento di Biologia, Università degli Studi di Padova, Via Ugo Bassi 58 B, Padova I-35131, Italy. alessandro.minelli@unipd.it
Evolution & Development
|May 28, 2009
Summary
Major evolutionary jumps in segment number, or saltation, are revealed in centipedes. A new scolopendrid centipede species shows a duplicated segment count, offering evidence for rapid evolutionary change in arthropod development.
Area of Science:
- Evolutionary biology
- Developmental biology (evo-devo)
- Arthropod morphology
Background:
- Segment number variation is a key evolutionary trait in arthropods.
- The evo-devo field suggests multiplicative phases in segment formation may drive evolutionary changes.
- Previous evidence for major saltational changes in segment number has been limited.
Purpose of the Study:
- To provide the first evidence of major phenotypic saltation in segment number within a centipede lineage.
- To investigate the evolutionary implications of segment number duplication in Scolopendromorpha.
Main Methods:
- Discovery and morphological analysis of a new centipede species.
- Comparative analysis of segment number with closely related species and the broader Scolopendromorpha taxon.
Main Results:
- A newly discovered species of scolopendrid centipede exhibits a duplicated segment number compared to its relatives.
- This finding represents a significant departure from the typical segment counts observed in over 700 known species of Scolopendromorpha.
Conclusions:
- The study provides concrete evidence for saltational evolution of segment number in centipedes.
- This discovery supports the hypothesis that multiplicative mechanisms in segment development can lead to rapid, major evolutionary changes in arthropod body plans.
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