Johanne Maad, PhD 


 

·   Postdoctoral researcher

·   Department of Biology

·   NTNU (Norwegian University of Science and Technology)

·   7491 Trondheim, Norway

·   Phone: (+ 47) 735 51269

·   Fax: (+ 47) 735 96100

·   E-mail: johanne.maad@bio.ntnu.no

·   Office: Realfagbygget, Blokk D, Rom DU2-117

·   Interests: Evolution, speciation, plant ecology, and pollination biology

Projects

Brief CV

Publications

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Projects

Evolution of flower size in Campanula rotundifolia (Campanulaceae) — effects of selection by pollinators and gene flow (postdoctoral project)

This project started in 2004 and is performed together with Scott Armbruster (NTNU, Norway) and Charlie Fenster (Univ. Maryland, USA)

The project focuses on the evolutionary mechanisms of pollination shifts, i.e. adaptive changes in floral morphology that are involved in evolution of pollination ecotypes. We have chosen to study Campanula rotundifolia because it exhibits variation in flower size: lowland populations have small-flowers and alpine populations have large flowers (see Shetler 1982). The main question asked is: How is natural selection driving the evolution of floral size in Campanula rotundifolia and what are the effects of gene flow?

Click here to view poster that was presented at the XVII International Botanical Congress in Vienna 2005.

 

 

Campanula rotundifolia

Evolution of pollen-ovule ratio and mating system in Collinsia (Scrophulariaceae)

This project is part of a large project that Scott Armbruster developed together with Bruce Baldwin (Univ. of California, Berkeley, USA) and Susan Kalisz (Univ. of Pittsburgh, USA).

My part of the project started in 2002 and aims at investigating the evolution of pollen ovule rations within the genus Collinsia in a phylogenetic context. The species exhibit mixed-mating at various degrees. Recent phylogenies (Armbruster et al 2002, Baldwin & Armbruster 2002) indicate that shifts between outcrossing and selfing have been in both directions within the genus. We are currently analysing phylogenetically corrected data with path analysis to investigate evolutionary pathways in the evolution of pollen-ovule ratios.

Selection and floral evolution in Platanthera bifolia and P. chlorantha (Orchidaceae)

This project is mainly an extension of my PhD studies. I mainly focus on the evolutionary mechanisms of pollination shifts, i.e. adaptive changes in floral morphology that are involved in evolution of pollination ecotypes, subspecies, and species. The sibling species Platanthera bifolia and P. chlorantha (Orchidaceae) exhibit a shift in inner floral morphology from narrow to wide column (and tongue and eye attachment of pollinaria) that may have been driven by selection on pollen receipt efficiency for a larger stigma (see Maad & Nilsson 2004). Additionally, spur length has been found to be important for reproductive success in P. bifolia and P. chlorantha (Nilsson 1988, Maad 2000, Maad & Alexandersson 2004, Maad & Nilsson 2004). Within both species there is a large geographic variation in spur length (L.A. Nilsson, unpublished data) that might reflect the length of the local pollinator’s tongue.

The main aim with the present project is to investigate the mechanisms of floral shifts that lead to new pollination ecotypes and species that utilise different pollinators or similar pollinators in different ways.

            

Platanthera bifolia                     Platanthera chlorantha

Literature

Baldwin, B G., Armbruster, W S. 2002. Collinsia antonina is evolutionarily distinct from C. parryi (Scrophulariaceae sensu lato). Madroño 49: 295-297

Armbruster W.S., Mulder C.P.H., Baldwin B.G., Kalisz S., Wessa B. and Nute H. 2002. Comparative analysis of late floral developement and mating-system evolution in tribe Colliniseae (Scrophulariaceae s.l.). Am. J. Bot. 89: 37-49.

Maad, J. 2000. Phenotypic selection in hawkmoth-pollinated Platanthera bifolia: Targets and fitness surfaces. Evolution 54: 123-123.

Maad, J., Nilsson, L.A. 2004. On the mechanism of floral shifts in speciation: gained pollination efficiency from tongue- to eye-attachment of pollinia in Platanthera (Orchidaceae). Biol. J. Linn. Soc. 83: 481-495.

Maad, J., 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.

Nilsson 1988. The evolution of flowers with deep corolla tubes. Nature 334: 147-149.

Shetler S.G. 1982. Variation and evolution of the nearctic harebells (Campanula subsect. Heterophylla). Cramer, Vaduz.

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Brief CV

General information

·   Born in 1970

·   Nationality: Swedish

·   Married to Urban Gunnarsson

·   Two children born in 1997 and 1999

·   Permanent residence: Trondheim, Norway

·   PhD in Systematic Botany 2002

 

Education and scientific merits

I did my undergraduate studies in biology at Uppsala University during 1989-1994.

Doctoral studies were conducted in plant systematics at Uppsala University during 1994-2002 with L. Anders Nilsson as supervisor. The thesis was entitled “Selection and floral evolution in Platanthera bifolia and P. chlorantha (Orchidaceae)”. All articles are published (see below). Dissertation was on 8 March, 2002 with Dr. Charlie Fenster as opponent.

I was employed within the project “Evolution of pollen-ovule ratio and mating system in Collinsia (Scrophulariaceae)” developed by Prof. Scott Armbruster, 2002-2003. (brief project description).

Presently I have a postdoctoral fellowship with Prof. Scott Armbruster at the Norwegian University of Science and Technology (2004-2006). The project is entitled “Evolution of flower size in Campanula rotundifolia (Campanulaceae) — effects of selection by pollinators and gene flow”. (brief project description).

Important funding

PhD funded by Uppsala University (1994-2002, corresponding to 4 years of full-time studies)

1-year postdoctoral fellowship funded by the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (2004)

2-year postdoctoral fellowship funded by the Norwegian Research Council (2005-2006)

Teaching

Teaching (mostly excursions and labs) at courses given by Uppsala University during 1994–2001 within the subjects of plant systematics and evolution corresponding to 1300 h (including prep.)

Teaching (mostly lectures) at courses given by NTNU during 2002–2004 within the subjects of ecology, plant systematics, evolution, and biogeography corresponding to 450 h (including prep.)

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Publications

1        Maad, J., Nilsson, L.A. 2004. On the mechanism of floral shifts in speciation: gained pollination efficiency from tongue- to eye-attachment of pollinia in Platanthera (Orchidaceae). Biol. J. Linn. Soc. 83: 481-495. (pdf)

2        Maad, J. and Reinhammar, L. G. 2004. Incidence of geitonogamy differs between two populations in the hawkmoth-pollinated Platanthera bifolia (Orchidaceae). Can. J. Bot. 82: 1586-1593. (pdf)

3        Maad, J., 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. (pdf)

4        Maad, J. 2002. Selection and floral evolution in Platanthera bifolia and P. chlorantha (Orchidaceae). Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 685. 26 pp. (link)

5        Maad, J. 2000. Phenotypic selection in hawkmoth-pollinated Platanthera bifolia: Targets and fitness surfaces. Evolution 54: 123-123. (pdf)

6        Bremer, K., Eklund, H., Gebrehivet M., Heidmarsson, S., Laurent, N., Maad, J., Niklasson, J., Nordin, A. 1996. On the delimitation of Matricaria versus Microcephala (Asteraceae: Anthemidae). Pl. Syst. Evol. 200: 263-271. Note: The authors are equally responsible for the content and listed in alphabetical order.

 

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Updated: 6 June, 2005