Paradoxical polyembryony? Embryonic cloning in an ancient order of marine bryozoans
| Autor: | Roger N. Hughes, Lars Johan Hansson, John D. D. Bishop, Andrew J Pemberton, Gary R. Carvalho, M. Eugenia D'Amato, Sean F. Craig, Margaret A. Harley |
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| Rok vydání: | 2006 |
| Předmět: |
Cyclostomata
Genetics Phylogenetic tree biology Genotype fungi Polyembryony Outcrossing Asexual reproduction biology.organism_classification Agricultural and Biological Sciences (miscellaneous) Brood Bryozoa Evolutionary biology Reproduction Asexual Animals Adaptation General Agricultural and Biological Sciences Atlantic Ocean Research Article |
| Zdroj: | Biology letters. 1(2) |
| ISSN: | 1744-9561 |
| Popis: | Prolific polyembryony is reported in few major taxa, but its occurrence has generated theoretical debate on potential conflict between sexual and asexual reproduction. It is, therefore, important to genetically confirm a widely cited inference, based on microscopy, that polyembryony characterizes marine bryozoans of the order Cyclostomata. Microsatellite genotyping of brooded embryos and maternal colonies conclusively demonstrated polyembryony, while genetic variation among broods within colonies indicated outcrossing via water-borne sperm, in the rocky-shore species Crisia denticulata . The characteristically voluminous brood chamber of cyclostomes is judged to be an adaptation linked to larval cloning and hence an indicator of polyembryony. We speculate that although the almost universal occurrence of polyembryony among crown-group Cyclostomata is probably attributable to phylogenetic constraint, adaptive consequences are likely to be significant. |
| Databáze: | OpenAIRE |
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