BEHAVIORAL EVIDENCE FOR FRUIT ODOR DISCRIMINATION AND SYMPATRIC HOST RACES OF RHAGOLETIS POMONELLA FLIES IN THE WESTERN UNITED STATES
Article first published online: 10 AUG 2012
© 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.
Volume 66, Issue 11, pages 3632–3641, November 2012
How to Cite
Linn Jr., C. E., Yee, W. L., Sim, S. B., Cha, D. H., Powell, T. H. Q., Goughnour, R. B. and Feder, J. L. (2012), BEHAVIORAL EVIDENCE FOR FRUIT ODOR DISCRIMINATION AND SYMPATRIC HOST RACES OF RHAGOLETIS POMONELLA FLIES IN THE WESTERN UNITED STATES. Evolution, 66: 3632–3641. doi: 10.1111/j.1558-5646.2012.01719.x
- Issue published online: 25 OCT 2012
- Article first published online: 10 AUG 2012
- Accepted manuscript online: 25 JUN 2012 08:58AM EST
- Received October 27, 2011 Accepted June 8, 2012
- Apple maggot fly;
- ecological speciation;
- flight tunnel;
- host plant volatiles;
The recent shift of Rhagoletis pomonella (Diptera: Tephritidae) from its native host downy hawthorn, Crataegus mollis, to introduced domesticated apple, Malus domestica, in the eastern United States is a model for sympatric host race formation. However, the fly is also present in the western United States, where it may have been introduced via infested apples within the last 60 years. In addition to apple, R. pomonella also infests two hawthorns in the West, one the native black hawthorn, C. douglasii, and the other the introduced English ornamental hawthorn, C. monogyna. Here, we test for behavioral evidence of host races in the western United States. through flight tunnel assays of western R. pomonella flies to host fruit volatile blends. We report that western apple, black hawthorn, and ornamental hawthorn flies showed significantly increased levels of upwind-directed flight to their respective natal compared to nonnatal fruit volatile blends, consistent with host race status. We discuss the implications of the behavioral results for the origin(s) of western R. pomonella, including the possibility that western apple flies were not introduced, but may represent a recent shift from local hawthorn fly populations.