Ronny Alexandersson, PhD

Department of Plant Ecology
Evolutionary Biology Centre (EBC)
Uppsala University
Norbyvägen 18 D
SE-752 36 Uppsala
Sweden 

Tel. +46 18 471 28 67 
Fax +46 18 55 34 19 
E-mail ronny.alexandersson@ebc.uu.se

Flower morphology and pollinators: ecology and evolution.

My general research interest is plant-animal interactions, mainly interactions between plant and pollinators. I finished my PhD in 1999 at Umeå University in northern Sweden and did 1999 to 2000 post-doctoral research at the University of Natal in Pietermaritzburg, South Africa together with Dr. S. D. Johnson.

My research could be divided into two main projects:

1. Reproductive ecology and population dynamics of the deceptive orchid Calypso bulbosa. This study was part of my PhD project and I study how a non-rewarding reproductive system affects reproductive success in populations of different sizes, populations with different abundances of reward-producing plants, pollen dispersal distances and the genetic structure. Population dynamics is studied in five populations of different size by using matrix models.

2. Pollinator-mediated selection on flower and inflorescence morphology and how selection by pollinators may create geographical variation in flower morphology. I (and my three collaborators) work in three plant systems:

1. The bumblebee-pollinted, non-rewarding orchid Calypso bulbosa; together with Prof. Jon Ågren, Plant Ecology, EBC, Uppsala University, Sweden.
2. The hawkmoth-pollinated South African Iris Gladiolus longicollis; together with Dr. S. D. Johnson, University of Natal. South Africa.
3. The moth-pollinated, rewarding orchid Platanthera bifolia; together with J. Maad, Systematic Botany, EBC, Uppsala University, Sweden.

Recent publications

• Maad, J. och Alexandersson, R. 2004. Variable selection in Platanthera bifolia (Orchidaceae): phenotypic selection differed between sex functions in a drought year. J. Evol. Biol. 17: 642-650.
• Johnson, S. D., Alexandersson, R. och Linder, H. P. 2003. Experimental and phylogenetic evidence for floral mimicry in a guild of fly-pollinated plants. Biol. J. Linn. Soc. 80: 289-304.
• Alexandersson, R. and S. D. Johnson. 2002. Pollinator-mediated selection on flower-tube length in a hawkmoth-pollinated Gladiolus (Iridaceae). Proc. R. Soc. Lond. B (2002) 269: 631-636.
• Alexandersson, R. and J. Ågren. 2000. Genetic structure in the nonrewarding, bumblebee-pollinated orchid Calypso bulbosa. Heredity 85:401-409.
• Alexandersson, R. and J. Ågren. 1996. Population size, pollinator visitation and fruit production in the deceptive orchid Calypso bulbosa. Oecologia 107:533-540.