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Cryptic genetic variation and paraphyly in ravens
K E Omland1, C L Tarr, W I Boarma
1Molecular Genetics Laboratory, National Zoological Park, Washington, DC 20008,USA. omland@umbc.edu
Proceedings. Biological Sciences
|February 24, 2001
Summary
Genetic analysis reveals two distinct groups within the widespread common raven (Corvus corax), challenging assumptions of uniformity. These findings highlight cryptic genetic diversity in widely distributed bird species.
Area of Science:
- Ornithology
- Evolutionary Biology
- Genetics
Background:
- Widespread species with uniform morphology may conceal significant genetic diversity.
- The common raven (Corvus corax) exhibits extensive Northern Hemisphere distribution but lacks clear phenotypic variation.
Purpose of the Study:
- To investigate cryptic genetic variation within the common raven population.
- To determine the genetic structure and evolutionary history of Corvus corax across its range.
Main Methods:
- Mitochondrial DNA sequencing and analysis of nuclear microsatellite markers.
- Sampling of tissue from common ravens across their extensive geographic range.
Main Results:
- A deep genetic divergence was identified between western U.S. ravens (California clade) and those from the rest of the world (Holarctic clade).
- Mitochondrial sequences showed over 4% divergence between clades, supported by microsatellite data.
- The Chihuahuan raven (Corvus cryptoleucus) was found to be genetically nested within the common raven, suggesting a complex evolutionary relationship.
Conclusions:
- The common raven may comprise at least two distinct genetic lineages that may be in the process of re-establishing contact.
- Morphological uniformity can mask substantial underlying genetic differentiation in widespread species.
- Conservation and management strategies may need to consider these distinct genetic groups.
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