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I lärarutbildningar beskrivs ofta såväl nationellt som internationellt den klyfta som finns mellan de verksamhetsförlagda och de högskoleförlagda delarna av utbildningarna. Det görs i flera lärarutbildningar ansträngningar att minska denna klyfta genom en närmare integration av dessa delar och inte minst fokuseras handledningens betydelse. Den arbetsintegrerade lärarutbildning som undersöks i föreliggande studie är ett resultat av ett sådant samarbete mellan en högskola och skolhuvudmän i en region med 15 kommuner. Studien syftar till att belysa arbetsintegrerade utbildningarnas attraktivitet och hur de arbetsintegrerade utbildningarna stödjer lärarstudenters möjlighet att utvecklas i läraryrket under sin utbildning. Ett huvudsakligt avstamp tas i Lave & Wengers teori ”situated learning” som bl.a. berör yrkesutbildningar. Det empiriska dataunderlaget utgörs av enkäter som analyserats utifrån såväl kvantitativa som kvalitativa aspekter. Sammanfattningsvis är slutsatserna att arbetsintegrerad lärarutbildning är attraktiv och ger lärarstudenterna möjlighet att utvecklas i läraryrket, men det finns flera områden som behöver utvecklas. De arbetsintegrerade utbildningarna är kvalificerade utbildningar, som för lärarstudenterna inte bara handlar om vad en lärare bör göra utan i huvudsak handlar om en möjlighet att befinna sig i något. Detta kan ses som ett unikt fokus vad gäller lärarutbildningar vilket kräver ett kontinuerligt utvecklingsarbete av personal i såväl högskola som i skolverksamhet i samverkan med lärarstudenter. Slutsatsen är att den arbetsintegrerade utbildningen utgöra en möjlighet att minska den klyfta som finnas mellan akademi och skolverksamhet., In teacher education, both nationally and internationally, the gap that exists between the work-based and the university-based parts of the education is often described. Efforts are being made in different teacher educations to reduce this gap through a closer integration of these parts, and not least the importance to improve student supervision. The work-integrated teacher education examined in the present study is a result of such a collaboration between a university and school in a region with 15 municipalities. The study aims to shed light on the attractiveness of work-integrated educations and how the work-integrated educations support teacher students' opportunity to develop their teaching skills. A starting point is taken in Lave & Wenger's theory "situated learning" which i.a. concerns vocational training. The empirical data base consists of surveys that have been analyzed on the basis of both quantitative and qualitative aspects. The conclusions are that work-integrated teacher education is attractive and gives teacher students the opportunity to develop their teaching skills. The work-integrated education is a qualified education, which for the teacher students are not just about what a teacher should do but mainly about an opportunity to learn and at the same time to be in something. The conclusion is that the work-integrated education constitutes an opportunity to reduce the gap that exists between university and school activities.

We investigated patterns of flower-size variation along altitudinal gradients in the bee-pollinated perennial Campanula rotundifolia (Campanulaceae) by examining 22 Norwegian populations at altitudes between 240 and 1100 m a.s.l. We explored potential mechanisms for the underlying pattern by quantifying pollinator-faunal composition, pollinator-visitation rates and pollen limitation of seed set in subsets of the study populations. Despite a decrease in plant size, several measures of flower size increased with elevation. Bumble bees were the main pollinators at both alpine and lowland sites in the study area. However, species composition of the pollinator fauna differed, and pollinators were larger in higher-elevation than in lower-elevation sites. Pollinator visitation rates were lower at higher-elevations than at lower elevations. Pollen limitation of seed set did not vary significantly with altitude. Our results are consistent with differences in bumble-bee size and visitation rates as causal mechanisms for the relatively larger flowers at higher elevations, in three non-mutually exclusive ways: 1) Larger flowers reflect selection for increased attractiveness where pollinators are rare. 2) Larger and fewer flowers represent a risk avoidance strategy where the probability of pollination is low on any given day. 3) Flower size variation reflects selection to improve the fit of pollinators with fertile structures by matching flower size to pollinator size across sites.

We estimated selection on three morphological characters in the hermaphroditic, hawkmoth-pollinated orchid Platanthera bifolia and explored selection surfaces through male and female function. The work was carried out in northern Sweden during two flowering seasons (1994 and 1995) in one natural population and one season (1995) in another natural population. Fitness was estimated as number of pollinia removed (male function) and number of fruits produced (female function). We detected directional selection towards larger inflorescence size (flower number) through both sex functions in both populations in 1995. In 1994, with an unusually dry growing season, 78% of the individuals failed to set any fruit, and there was selection for larger inflorescences only through male function. In this year, there was selection towards longer flower spurs, which could be a direct or indirect effect of spurs being shortened by drought. The results demonstrate that selection patterns may vary temporally and spatially, and that the 'male function hypothesis' may be applicable as female function is more resource dependent than male function.

This work explores the mechanism of floral shifts that may result in speciation. The model organisms chosen were the moth-pollinated pollinator-limited orchid species Platanthera bifolia and P. chlorantha. P. bifolia exhibits tongue-attachment of pollinia on pollinators, a character state that has been found previously to be ancestral. The close relative P. chlorantha exhibits the derived state of eye-attachment of pollinia on pollinators. We reasoned that differences between the species in pollination efficiency could give insights into the mechanism of floral shifts and thus cladogenesis. Four populations per species were investigated. In three populations, where the species were growing intermixed and were sharing pollinators, there was significant difference in the pollen export and import efficiency per visit-night (night with pollen export and/or import) between the two species. P. bifolia exported pollinia more efficiently but imported pollen less efficiently than did P. chlorantha. Pollen import was 1.74 times faster in P. chlorantha (eye-attachment) than it was in P. bifolia (tongue-attachment). P. chlorantha had a lower risk of interference between pollen import and export. An increase in fitness through greater speed and efficiency of pollen import due to an enlargement of the stigmatic surface and a reduction in the risk of sexual interference may therefore be mechanisms of the floral shift from tongue- to eye-attachment of pollinia on pollinators.