<p>Syftet med rapporten var att undersöka hur barn i åldern fyra-fem år tänker om sin egen kropp, vilka uppfattningar om kroppen som finns. Sju barn har deltagit genom kvalitativa intervjuer och en uppföljning ca 18 månader senare visar hur uppfattningarna förändrats eller utvecklats. Barnen blev även erbjudna att måla en teckning som visade insidan på en människokropp.</p><p>   Barnens svar var bundna till situationer och uppfattningarna om kroppen hade utvecklats sedan de första intervjuerna, även om en del svar var ganska lika. Barnens spontana svar om den egna kroppen var många; det finns ett hjärta, hjärna, skelett, blod för att nämna några svar. Några av barnen kände till hjärtat och hjärnans funktion.</p><p>   Barnen fick också besvara frågor om vad som händer med maten vi äter, vad som händer med människokroppen när man blir gammal och om sjukdom. Fyra barn berättade att maten först hamnar i magen och därefter i rumpan/toaletten, de andra barnen menade att maten stoppar i magen. När man blir gammal menade några barn att man dör eller att kroppen blir trött och orkar mindre. Barnen berättade även om olika sjukdomar de haft eller känner till, om medicin och att man kan bli sjuk genom smitta.</p> / <p>The purpose of the essay was to examine how children of the age of four to five years old think about their own body, and their understanding of the body. Seven children have participated through qualitative interviews and a follow-up after about 18 months shows how the comprehensions have changed or developed. The children were also offered to make a drawing that showed the inside of a human body.</p><p>   The answers of the children were tied to situations and the comprehensions of the body had evolved since the first interviews, even though some answers were rather similar. The children's spontaneous thoughts about their own body were many; there is a heart, brain, skeleton, and blood, to name a few answers. Some of the children know the function of the heart and brain.</p><p>   The children were also asked about what happens to the food we eat, what happens with the human body when you grow old, and about illness. Four children said that the food at first ends up in the stomach and then in the rump/toilet, the other children advocated that the food will stop in the stomach. Some children advocated that you die when you grow old or that the body gets tired and have less energy. The children also talked about different diseases they had or knew about, about medicine and the fact that it's possible to get a disease through contagion.</p>

Tolerance to herbivory is the ability of plants to maintain fitness in spite of damage. The goal of this thesis is to investigate the genetic variation and expression of tolerance within species, determine whether and in what conditions tolerance has negative side-effects, and how tolerance is affected by different ecological factors. Tolerance is investigated with special focus on the effects of different damage types, competitive regimes, history of herbivory, and polyploidization in plants. Studies are conducted as a literature review and three experiments on two cruciferous species Raphanus raphanistrum and Cardamine pratensis. In the tolerance experiments, plants are subjected to artificial damage solely, or in a combination with natural damage. A literature review was conducted in order to investigate the effects of damage method. We found that traits related to tolerance, such as growth and fitness were not as sensitive in regard to damage method as measures of induced chemical traits, or measures of secondary herbivory. Genetic variation of tolerance was demonstrated within populations of R. raphanistrum and between subspecies of C. pratensis. In R. raphanistrum, traits involved in floral display and male fitness were positively associated with plant tolerance to herbivore damage. A potential cost of tolerance was demonstrated as a negative correlation between levels of tolerance in high and low competitive regimes. I found no evidence of other proposed costs of tolerance in terms of highly tolerant plants suffering of reduced fitness in the absence of herbivores or trade-offs in terms of a negative association between tolerance to apical and leaf damage, or between tolerance and competitive ability. In C. pratensis, higher ploidy level in plants involved higher levels of tolerance measured as clonal reproduction. Furthermore, populations exposed to higher levels of herbivory had better tolerance than populations exposed to lower levels of herbivory. In this thesis, I demonstrate evidence of different components for the evolution of tolerance in plants: genotypic variation, selective factors in terms of costs and ploidization, and selective agents in terms of changing environment or herbivore pressure.

Syftet med rapporten var att undersöka hur barn i åldern fyra-fem år tänker om sin egen kropp, vilka uppfattningar om kroppen som finns. Sju barn har deltagit genom kvalitativa intervjuer och en uppföljning ca 18 månader senare visar hur uppfattningarna förändrats eller utvecklats. Barnen blev även erbjudna att måla en teckning som visade insidan på en människokropp.    Barnens svar var bundna till situationer och uppfattningarna om kroppen hade utvecklats sedan de första intervjuerna, även om en del svar var ganska lika. Barnens spontana svar om den egna kroppen var många; det finns ett hjärta, hjärna, skelett, blod för att nämna några svar. Några av barnen kände till hjärtat och hjärnans funktion.    Barnen fick också besvara frågor om vad som händer med maten vi äter, vad som händer med människokroppen när man blir gammal och om sjukdom. Fyra barn berättade att maten först hamnar i magen och därefter i rumpan/toaletten, de andra barnen menade att maten stoppar i magen. När man blir gammal menade några barn att man dör eller att kroppen blir trött och orkar mindre. Barnen berättade även om olika sjukdomar de haft eller känner till, om medicin och att man kan bli sjuk genom smitta. / The purpose of the essay was to examine how children of the age of four to five years old think about their own body, and their understanding of the body. Seven children have participated through qualitative interviews and a follow-up after about 18 months shows how the comprehensions have changed or developed. The children were also offered to make a drawing that showed the inside of a human body.    The answers of the children were tied to situations and the comprehensions of the body had evolved since the first interviews, even though some answers were rather similar. The children's spontaneous thoughts about their own body were many; there is a heart, brain, skeleton, and blood, to name a few answers. Some of the children know the function of the heart and brain.    The children were also asked about what happens to the food we eat, what happens with the human body when you grow old, and about illness. Four children said that the food at first ends up in the stomach and then in the rump/toilet, the other children advocated that the food will stop in the stomach. Some children advocated that you die when you grow old or that the body gets tired and have less energy. The children also talked about different diseases they had or knew about, about medicine and the fact that it's possible to get a disease through contagion.

Throughout history species has gone extinct due to anthropogenic activities. During the last century efforts have been done to reintroduce species back into the wild. Zoos that originally were created as amusement parks for people have today a new purpose; to keep and breed species in captivity for later reintroductions in the wild. However a relaxed environment such as a zoo leads to a general fitness decline of up to 40% per generation in captivity. The probability of a successful reintroduction of a species that has been bred in a zoo will be lower the longer time it has been kept in captivity. The reintroduction of a captive bred species can also cause secondary extinctions and other negative effects on the food-web. Both changes in the community caused by the loss of a species and changes in the species itself caused by captivity can be expected to affect the outcome of a reintroduction attempt. Using a modeling approach I here investigate how the reintroduction of a captive bred species (at three different trophic levels; basal, intermediate and top predator species) affects a food-web and what risks there are in reintroducing it. A Lokta-Volterra model with type II functional response is used. I investigate three scenarios: the reintroduction of a species with 0% change in its attributes, 40% change in its attributes and 75% change in its attributes. It was found that the most important factor for reintroduction success when reintroducing a species is whether it is a producer species (basal species) or a consumer species (intermediate and top predator species). The producer species were most sensitive to the changes in their attributes, whilst consumer species were more sensitive to change in the food-web (Euclidian distance). The producer species were found to cause most secondary extinctions in all scenarios, hence indicating that it is a bottom-up controlled food-web. The present study suggests that the success of a reintroduction attempt is affected both by the degree of changes in the food web caused by the initial loss of the species and the degree of change in the species itself caused by captivity.

The extinction risk of threatened species has traditionally been assessed by the use of tools of Population Viability Analysis (PVA). Species interactions, however, have seldom been accounted for in PVA:s. The omission of species interactions in risk assessments may further lead to serious mistakes when setting target sizes of populations. Even a slight abundance decrease of a target species may result in changes of the community structure; in the worst case leading to a highly impoverished community. Of critical importance to conservation is therefore the question of how many individuals of a certain population that is needed in order to avoid this kind of consequences. In the current study, a stochastic multispecies model is used to estimate minimum ecological viable populations (MEVP); earlier defined as “the minimum size of a population that can survive before itself or some other species in the community becomes extinct”. The MEVP:s are compared to population sizes given by a single species model where interactions with other species are treated as a constant source incorporated in the species specific growth rate. MEVP:s are found to be larger than the population sizes given by the single species model. The results are trophic level dependent and multispecies approaches are suggested to be of major importance when setting target levels for species at the basal level. Species at higher trophic levels, however, are altogether more prone to extinction than species at the basal level, irrespective of food web size and food web complexity.

<p>In birds like the Zebra finch (Taeniopygia guttata) the female, but not the male develop a brood patch upon incubation of eggs. The brood patch functions to increase heat exchange between the bird and the eggs. Development of the brood patch includes de-feathering, increased vascularization and edema formation. The increased vascularization is due to the development of arteriovenous anastomoses, AVA. The AVA are thermoregulatory vessels involved in cold induced vasodilation, CIVD, demonstrated to occur in the brood patch. Nitric oxide, NO, which is a well known vasodilator is a candidate substance for involvement in CIVD. In this study a NO-generating gel was applied to the brood patch of male and female zebra finches. Vasodilation was found to be markedly larger in females than in males. The larger vasodilation in the female brood patch is probably because NO vasodilate AVA selectively more than any other vessels. The study also investigated whether vasodilation would cause an increase in brood patch temperature. No definite changes in brood patch temperature could be observed and no conclusions could be drawn in the matter.</p>

Altitudinal gradients offer attractive opportunities for studies of population differentiation in response to environmental heterogeneity. In this thesis, I examined population differentiation along altitudinal gradients by combining common-garden experiments with field studies and experiments in alpine, subalpine and boreal populations of the perennial herb Solidago virgaurea. More specifically, I determined whether leaf physiology in terms of nitrogen concentration and resorption, flowering phenology, flower production and reproductive effort vary along altitudinal gradients. Nitrogen concentration in green leaves were higher in alpine than in subalpine and boreal populations. These differences persisted when plants were grown from seeds in a common-garden experiment at two sites, suggesting that the differences have a genetic component. There was mixed support for a trade-off between maximized carbon gain through the maintenance of high nitrogen concentration, and minimized nitrogen loss through high resorption. In their natural habitats alpine populations began flowering later than subalpine populations, but this difference was reversed when plants were grown in a common environment. This suggests that genetic differences among populations counteract environmental effects and reduce phenotypic variation in flowering time among populations. Flowering time thus shows countergradient genetic variation in S. virgaurea. In a common-garden experiment, boreal populations produced more flowers and had a higher reproductive effort than subalpine and alpine populations indicating habitat-specific genetic differences in reproductive allocation. In a field study, which included three populations, seed set was close to zero in the alpine population, intermediate in the subalpine population, and high in the boreal population. Experimental flower removal showed that seed production was associated with a considerable cost in terms of reduced flowering propensity the following year, but did not support the hypothesis that a large floral display is important for pollination success.

The aim of this thesis was to increase knowledge about metapopulation and metacommunity processes in patchy, dynamic landscapes, using epiphytic bryophytes as a model system. Host trees and deciduous forest stands in the coniferous landscape are patchy, temporal and undergo changes in habitat quality during succession. Epiphytes must track this dynamic habitat network for their long-term survival. Community patterns at different spatial scales were explored and linked to regional metapopulation processes and local population dynamics. Spatial structuring in species richness both at a local and regional scale indicated stronger dispersal limitation but lower sensitivity to habitat quality in species with large asexual than in species with small sexual diaspores. In sexually dispersed species, a strong rescue effect was indicated by a bimodal frequency distribution of the species and by increasing local abundance with increasing patch connectivity. Present connectivity to other deciduous forest patches had positive effects on richness of asexually dispersed species, whereas richness of sexually dispersed species was instead related to the landscape connectivity 30 years ago. A study of local growth and reproduction suggested that this is caused by delayed sexual, but not asexual, reproduction. Habitat conditions affected the production of sporophytes, but not of asexual diaspores. No differences in either growth rates or competitive abilities among species with different dispersal and life-history strategies were found. In vitro experiments showed that establishment is higher from large asexual diaspores than from small sexual. Establishment of all diaspore types was limited by pH. There were indications of trade-offs between high germination and protonemal growth rates, desiccation tolerance and a rapid development of shoots from protonema. The results indicated that the epiphyte metacommunity is structured by two main trade-offs: dispersal distance (diaspore size) versus age at first reproduction, and dispersal distance versus sensitivity to habitat quality. Trade-offs in species traits may have evolved as a consequence of conflicting selection pressures imposed by habitat turnover, connectivity and irregular water supply rather than by species interactions. Syndromes of interrelated species traits imply that fairly small changes in habitat conditions can lead to distinct changes in metacommunity diversity: the results indicate that increasing distances among patches cause most harm to asexually dispersed species, whereas cuttings of forests of high age and quality as well as increasing patch dynamics are most harmful to sexually dispersed species. / Senarelagd disputation från: 2009-09-26, Lindahlsalen, EBC, Villavägen 9, 75236 Uppsala, Uppsala, 10:00