Brainless but not clueless: earthworms boost their ejaculates when they detect fecund non-virgin partners
| Autor: | Alberto Velando, Jorge Domínguez, Julio Eiroa |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Male
media_common.quotation_subject Theoretical models Disorders of Sex Development Zoology Fertility Biology General Biochemistry Genetics and Molecular Biology Sexual Behavior Animal Hermaphrodite medicine Animals Disorders of sex development Mating Oligochaeta Sperm competition reproductive and urinary physiology General Environmental Science media_common General Immunology and Microbiology Ecology urogenital system General Medicine medicine.disease biology.organism_classification Sperm Spermatozoa Female General Agricultural and Biological Sciences Research Article |
| Zdroj: | Proceedings. Biological sciences. 275(1638) |
| ISSN: | 0962-8452 |
| Popis: | In many animals in which females store sperm, males may detect female mating status and, in order to outcompete rival sperm, increase ejaculate size when copulating with non-virgin females. Although most studies have been restricted to organisms with separate sexes, theoretical models suggest that sperm competition should also be an important selective agent shaping life-history traits in simultaneous hermaphrodites. Nevertheless, the empirical support for ejaculate adjustment in a mating opportunity is scarce in hermaphrodites. In the present study, we performed a double-mating experiment to determine whether earthworms ( Eisenia andrei ) detect the mating status of their partners and whether they respond by adjusting their ejaculate. We found that earthworms triplicated the donated sperm when mating with a non-virgin mate. Moreover, such increases were greater when the worms were mated with larger (more fecund) partners, indicating that earthworms perform a fine-tune control of ejaculate volume. The results of the present study suggest that, under high intensity of sperm competition, partner evaluation is subject to intense selection in hermaphrodite animals, and donors are selective about to whom they donate how much sperm. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|