ISSN:
1432-0762
Keywords:
Keywords Mating intervals
;
Sperm precedence mechanisms
;
Spermatophores
;
Tenebrio molitor
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract When females mate with more than one male, the ensuing sperm competition leads to the evolution of male mechanisms that skew paternity. Males of the yellow mealworm beetle (Tenebrio molitor) transfer a spermatophore to females during copulation, but sperm release and storage occur later. We investigated how the interval between two matings with different males affects sperm precedence by varying the interval between the copulations so that the second mating was either: (1) before sperm release from the first spermatophore (〈5 min); (2) after sperm release but before spermatophore ejection (15–20 min); (3) after spermatophore ejection but before sperm storage (4 h), or (4) after complete sperm storage (24 h). We collected offspring over a period of 2 weeks and determined paternity by protein electrophoresis. There was second-male sperm precedence in all treatments, but when the interval was 〈5 min, the second male usually (86% of cases) had complete sperm precedence (i.e., P 2=1). Investigations into the mechanism of second-male sperm precedence during 〈5-min mating intervals indicate that sperm release from the first spermatophore is inhibited, a phenomenon which has not been previously documented.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s002650000257
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