Females influence sperm storage and use in the yellow dung flyScathophaga stercoraria(L.)

✍ Scribed by Paul I. Ward

• Book ID: 104654442
• Publisher: Springer
• Year: 1993
• Tongue: English
• Weight: 694 KB
• Volume: 32
• Category: Article
• ISSN: 0340-5443
• DOI: 10.1007/bf00183786

✦ Synopsis

The influence of the female on the process of sperm storage and use was examined. Copula duration, the condition of the female and whether or not a copula terminated naturally influenced the number of spermathecae (of three) in which once-mated females stored sperm. Females stored more sperm the larger their mate and the sperm from larger males were stored more unevenly amongst the spermathecae than were those from smaller males. Double-mated females had sperm in fewer spermathecae the larger the second of their mates and these spermathecae tended to be the ones which lay together within the female. The P2 values over three successive clutches were constant and sperm precedence was complete when the larger male was second to mate but began low and increased over subsequent clutches when the smaller male mated second. These results suggest females prefer, and are able, to use the sperm of larger males to fertilise their eggs. It is proposed that multiple spermathecae in Diptera have evolved to give females better control over offspring paternity.