Evol Ecol Res 1: 223-234 (1999)     Full PDF if your library subscribes.

Differences in mating behaviour and sex ratio between three sibling species of Nasonia

Mark D. Drapeau and John H. Werren

Department of Biology, University of Rochester, Rochester, NY 14627, USA

Address all correspondence to Mark D. Drapeau, Department of Ecology and Evolutionary Biology, 321 Steinhaus Hall, University of California, Irvine, CA 92697, USA.
e-mail: mdrapeau@uci.edu


Mating in Nasonia wasps has traditionally been thought to occur on or around their pupal fly host, after emergence. Here we report the occurrence of within-host mating (WHM) in Nasonia. Within-host mating is interesting as a simple behavioural trait that can have a strong effect both on the level of inbreeding and the level of interspecific mating in a species. A survey of WHM levels was performed on 17 recently collected strains of Nasonia from three sibling species: N. vitripennis, N. giraulti and N. longicornis. Both N. giraulti and N. longicornis mated within hosts at significantly higher rates than N. vitripennis. The mean (± S.D.) percentage of females mating within hosts was 64.4 ± 16.6 in N. giraulti, 9.1 ± 8.5 in N. longicornis and 1.0 ± 2.1 in N. vitripennis. Within-host mating in N. giraulti and N. longicornis may represent a mechanism for escaping hybridization with N. vitripennis, which often co-occurs microsympatrically in birds’ nests with the other two allopatric species. Since WHM presumably increases local mate competition (LMC) and inbreeding among progeny, elevated levels of WHM should select for more female-biased sex ratios. Mean one-foundress sex ratios were calculated for 20 Nasonia strains, with most of these strains being the same as those in the general WHM assay. As expected, N. giraulti had significantly more female-biased sex ratios than both N. longicornis and N. vitripennis. The implications of WHM for the population dynamics of Nasonia are discussed.

Keywords: adaptation, inbreeding, local mate competition, mating behaviour, Nasonia, sex ratio, sibling species.

IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.


        © 1999 Mark D. Drapeau. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.

       Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.

       All copies of abstracts and articles must preserve their copyright notice without modification.