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A Noninvasive Method For In situ Determination of Mating Success in Female American Lobsters (Homarus americanus)
Published on: February 7, 2014
Sex and ostracods.
J A Chaplin1, J E Havel, P D Hebert
1Dept of Zoology, University of Guelph, Ontario, Canada N1G 2W1.
Trends in Ecology & Evolution
|January 18, 2011
Summary
Asexual reproduction, or parthenogenesis, is common in ostracods, crustaceans with a strong fossil record. Some asexual lineages have persisted for over 70 million years, challenging evolutionary theories on the necessity of sexual reproduction.
Area of Science:
- Evolutionary Biology
- Zoology
- Genetics
Background:
- The evolutionary persistence of sexual reproduction is a long-standing question in biology.
- Asexual reproduction (parthenogenesis) offers potential advantages but is often considered evolutionarily unstable.
- Ostracod crustaceans exhibit a high frequency of transitions to parthenogenesis and possess a rich fossil record.
Purpose of the Study:
- To investigate the evolutionary factors maintaining sexual reproduction.
- To understand the origin and long-term persistence of asexual lineages in ostracods.
- To explore the genetic basis for the success of parthenogenetic ostracods.
Main Methods:
- Analysis of ostracod fossil records to determine the historical incidence of parthenogenesis.
- Genetic studies to investigate the molecular mechanisms underlying asexual reproduction in ostracods.
- Comparative evolutionary analyses of sexual and asexual ostracod lineages.
Main Results:
- Ostracods show the highest known incidence of transitions to parthenogenesis among animal groups.
- The fossil record indicates some parthenogenetic ostracod lineages have persisted for at least 70 million years.
- Ongoing genetic research is identifying the basis for the sustained success of asexual reproduction in these crustaceans.
Conclusions:
- Ostracods provide a unique model system for studying the evolution and maintenance of sex versus asexual reproduction.
- The long-term survival of parthenogenetic ostracods challenges the "Red Queen" hypothesis, which posits that sex is necessary to coevolve with parasites.
- Further genetic and experimental research on ostracods can illuminate the evolutionary dynamics of reproductive strategies.
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