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Multiple paternity analysis in the thornback ray Raja clavata L
Malia Chevolot1, Jim R Ellis, Adriaan D Rijnsdorp
1Department of Marine Benthic Ecology and Evolution, Center for Ecological and Evolutionary Sciences, University of Groningen, Postbus 14, 9750 AA Haren, The Netherlands. malia.chevolot@univ-bpclermont.fr
The Journal of Heredity
|September 29, 2007
Summary
Female thornback rays (Raja clavata) exhibit polyandry, with egg clutches sired by multiple fathers. This finding is crucial for understanding skate mating systems and conservation efforts.
Area of Science:
- Marine Biology
- Conservation Genetics
- Ichthyology
Background:
- Skates (Rajidae) possess life history traits (slow growth, low fecundity, late maturity) making them vulnerable to overexploitation.
- Understanding mating systems is vital for effective fisheries management and conservation of skate populations.
- Reproductive behaviors, particularly mating systems, remain poorly understood in many skate species.
Purpose of the Study:
- To investigate the mating system of the thornback ray (Raja clavata).
- To determine if multiple paternity occurs in Raja clavata egg clutches.
- To provide insights into the reproductive biology of oviparous elasmobranchs.
Main Methods:
- Analysis of egg clutches from four wild-caught Raja clavata females.
- Utilized five highly polymorphic microsatellite loci for genetic analysis.
- Employed the reconstructed multilocus genotypes method to determine progeny parentage.
Main Results:
- All four analyzed egg clutches demonstrated multiple paternity.
- Each clutch was sired by a minimum of 4 to 6 distinct fathers.
- Confirmed polyandry in female Raja clavata.
Conclusions:
- This study provides the first evidence of multiple paternity in a rajiform species and any oviparous elasmobranch.
- The observed polyandry in Raja clavata may be a natural phenomenon or a response to exploitation pressures.
- Findings highlight the need for further research into skate reproductive strategies for conservation and management.
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