Insects are guided to potential host plants by visual and olfactory signals. Upon arrival they encounter various taste stimuli, ultimately deciding whether the plant is a proper food or oviposition source. The detection of gustatory stimuli by contact chemosensilla has been studied in several insect species, and intracellular recordings from neurons in the subesophageal ganglion (SOG) in Heliothis virescens have revealed responses to several taste qualities mediated by different appendages. However, how the gustatory information is further processed in higher gustatory areas and how it may lead to taste-related behavior is poorly understood. Important questions are where gustatory neurons project in the protocerebrum and how they process information mediated by different appendages, i.e. the coding of taste identity and location. These topics were investigated in the present study using intracellular recordings combined with fluorescent staining techniques. The recordings were carried out in vivo from single neurons in the protocerebrum of the moth Heliothis virescens, while concurrently stimulating the contact chemosensilla of the antennae and the proboscis with gustatory and mechanosensory stimuli. The protocerebral neurons showed large diversity in their response tuning breadth, some responding specifically to one tastant applied at one appendage, whereas others responded to several tastants applied at one, two or three appendages. Some of the neurons were successfully stained, all of them partially or entirely located in the protocerebrum. In addition, some of the neurons targeted the SOG/tritocerebrum, the antennal mechanosensory and motor center (AMMC) and the antennal lobes (ALs). The present results point to different processing streams of taste information in the protocerebrum, where the narrowly tuned neurons seem to participate in a labelled line (LL) and the others in an across fiber pattern (AFP) mechanism. Moreover, the important role of the gustatory system for influencing behavior is substantiated by the widespread gustatory innervation of the protocerebrum. These projections suggest a role for the gustatory system in modulating the activity of other sensory systems, in addition to the coding of taste information.

SamandragInsekt nyttar luktesansen til mange formål som er avgjerande for overlevnad og reproduktiv suksess. Ein veksande kunnskapsbase tyder på at miksturar av nokre få biologisk relevante plantevolatiler kan vekke atferdsmessige responsar i insekt medan einskilde volatiler har liten effekt. Mykje forsking er gjort på nevral prosessering av binære duftblandingar i det primære luktesenteret til insekt, men ein veit lite om korleis informasjon om blandingar av mange komponentar vert handsama i høgare ordens hjernesentra. Denne studien tok sikte på å utforske prosessering av informasjon om biologisk relevante plantedufter og komplekse duftblandingar i høgare ordens luktesentra i nattflyarten Heliothis virescens. Insekt vart stimulerte med primære plantedufter og komplekse duftblandingar medan intracellulære registreringar vart utførte på høgare ordens nevron i laterale og superiore protocerebrum. Nokre nevron vart òg karakteriserte morfologisk ved intracellulær fargeinjeksjon, og eit av desse nevrona vart rekonstruert digitalt i tre dimensjonar og registrert inn i eit standard hjerneatlas som er konstruert for denne arten. Nevrofysiologiske analyser viste at duftblandingane vekte responsar med høgare sannsyn enn enkeltdufter i desse høgare ordens nevrona. Mange nevron skilde mellom blandingar og enkeltkomponentar ved å svare med ulik styrke på dei to typane stimuli, men det var ikkje noko fast forhold mellom responsmønstera eit nevron utviste for ei blanding og responsmønstera nevronet utviste for komponentane i blandinga. Resultata viste òg at mange nevron kunne skilje mellom to komplekse blandingar som var kjemisk nært slekta. Blandingane vakte dei sterkaste responsane I storparten av nevrona, men eit nevron svarte spesifikt på berre éin primær odorant. Desse resultata tyda på at informasjon om primære plantedufter vert integrerte i høgare ordens nevron på ein ikkje-lineær måte som er spesifikk for kvar duftblanding og kvart enkelt nevron. Vidare utviser høgare ordens nevron primært synergi for duftblandingar, men informasjon om spesifikke enkeltdufter er òg bevart i høgare hjernesentra.

One major challenge in Asian aquaculture is the limited availability of carp fries. In order to establish out of season supply of fries, knowledge about the pineal melatonin clock and calendar function, and its influence on the reproductive system, is needed. Three experiments were carried out to examine pineal melatonin dynamics of mrigal carp (Cirrhinus mrigala), under natural outdoor, and manipulated photoperiods. Plasma melatonin profile of the mrigal carp kept under natural outdoor photoperiod reached a peak early in the dark phase, and then showed a tendency of falling plasma melatonin levels until daytime levels were reached at first light. The second experiment intended to induce production of melatonin at different times during the light phase, and gave production of melatonin only in late afternoon. This indicates a refractory period of the pineal gland during daytime, and that production of melatonin might be controlled by a circadian clock. In the third experiment, animals were exposed to continuous darkness. The resulting plasma melatonin profile was in accordance with subjective darkness and light, with a peak late in the dark phase. This further supports the assumption that a circadian clock controls pineal melatonin production and secretion in the mrigal carp.

The Black legged Kittiwake (<i>Rissa tridactyla</i>) is one of the more extensively studied seagull species, and much of their nesting behaviour and physiology concerning the breeding period has already been examined to a high degree. Its habitat choice is such that it has been able to cover much of the costal habitats on the northern hemisphere, from Spain in the south to Svalbard in the north. For this reason it encounters a high degree of variability when it comes to environmental challenges during its breeding season, leading to large fluctuations in inter-annual breeding success. As the environmental factor play such an important role in conservation, the ability to accurately estimate its effects on sea-bird populations, is of outmost importance. One step towards acquiring such knowledge is to measure the effects on the nestling, when exposing their parents to a known increase in energy expenditure; a procedure attempted in this study.Long-lived species, like the Kittiwake, have long been thought to maximize their fitness by restricting parental investment to a fixed level in each breeding attempt. By manipulating parental flight wing size at the start of the hatching period, we induced a handicap on the experimental nests. By measuring body condition (BCI) of parents and chicks, in addition to the baseline corticosterone (CORT) levels of the nestlings, this study aimed to investigate whether or not the offspring in the experimental nests would suffer any detrimental effects from increased foraging costs to their parents, by wing-clipping, in comparison to offspring of unmanipulated parents; and whether or not offspring gender played any role in this context. The offspring of wing-clipped parents showed no significant detrimental effects, neither on body condition or CORT levels in relation to the control nests. With regard to the CORT levels, the data actually suggested a more positive outcome, significantly lower CORT levels for larger nestlings, in the experimental nests than what was found for the control nests. Both males and females seemed to experience the same investment, as there was found no significant difference in size, BCI or CORT levels between them. The effect on the parents also did not show any significant difference between the groups on BCI or weight loss. Neither father nor mother showed any appreciable difference in their investment, measured as their BCI or on weight loss, although mothers was found to loos a larger proportion of their body mass, suggesting that they are willing to assist in a larger extent during chick rearing, in comparison to fathers. There was also detected a difference in nest attendance, where the treatment actually appeared to give a significant difference, with wing-clipped couples sing a longer time between each nest attention swap. Despite the results on the nest attendance, the lack of a considerable detrimental effect from the wing-clipping procedure could not be detected on neither parents nor the offspring. This study was therefore unable to say anything definitive with regard to parental investment theories. It would seem that the experimental procedure in this case was too weak to give a significant handicap, whether this was from the procedure itself, environmental factors or other, so far, unknown effectors.Although this study failed in its investigation on parent nestling tradeoffs, and gender relations regarding this; It has however, found a very strong correlation (P = 0.006) between handling time during blood sampling and CORT levels in time intervals below the 3 minutes. Suggesting that the widely accepted limit of 3 minutes handling time when sampling the baseline CORT level, might not be valid with regard to chicks during their growth face.

SammendragDen dominerende planktonorganismen i Atlanterhavet og Barentshavet er den calanoide kopepoden Calanus finmarchicus. Den er en nøkkelart i den marine næringskjeden, og har evnen til å lagre store mengder fett, som kan være den viktigste opptaksruten for lipofile forurensende stoffer til høyere trofiske nivå. C. finmarchicus er derfor betraktet som en økologisk relevant forsøks art.Ettersom en upassende respons til miljøbestemte og fysiologisk stimuli, som en årsak av toksiske effekter av forurensende stoffer, kan ha atskillige konsekvenser for overlevelse, selv på konsentrasjoner under dødelig nivå, er det viktig å undersøke adferds indikatorer for akvatisk toksisitet. Det ble totalt gjennomført fire eksponerings serier, hvor eksponerings media var WAFs basert på fersk og forvitret råolje. Eksponeringstiden var 24, 48, 72 og 96 timer. Endringer i flukt respons som en årsak av narkose indusert av olje eksponering ble målt. Parameterne som ble målt var flukt respons frekvens, flukt respons latens tid og utmattende effekter av repetitive hydrodynamiske forstyrrelser. Resultatet fra forvitret og fersk råolje eksponeringer viser at det skjer en nedgang i flukt respons frekvenser selv på konsentrasjoner langt under dødelig nivå, for alle eksponerings tider. Det ble derimot ikke funnet noen klar korrelasjon mellom råolje eksponering og endinger i latens tid eller utmattende effekter av repetitiv hydrodynamiske forstyrrelser.Tilstedeværelsen av signifikant reduksjon i flukt respons frekvenser i C. finmarchicus indikerer at endringer i flukt adferd kan fungere som endepunkt for toksiske effekter, av kjemikalier med konsentrasjoner under dødelig nivå, og kan blir brukt som en økologisk relevant biomarkør.

As human induced disturbance in alpine ecosystems have increased, more knowledge is needed about the long-term effects of restoration efforts in such environments. There are benefits with using native species in restoration in alpine ecosystems, but the establishment success of native species compared to non-native species, and their effect on the establishment of native species has not been evaluated in detail. We examined ten disturbed alpine sites 21 years after seeding with a commercial seed mix, with regard to vegetation cover, species richness and soil conditions, and compared them with reference sites in close vicinity. After 21 years seeded sites had more vegetation cover, but native vegetation cover and species richness was larger in reference sites. Soil material did have a significant effect on vegetation cover, with less vegetation establishing as dominating soil particle size increased. However, native vegetation cover remained the same with increasing soil material. The effects of a native species, Festuca ovina, was compared with the effects of the main ingredient from the commercial seed mix used in 1989, Festuca rubra, on the establishment of the native Betula nana. Festuca rubra established slightly better than F. ovina on all soil types in the greenhouse experiment, but had larger plant size. B. nana experienced competition from both Festuca species, but less from F. ovina. The species F. ovina facilitated for B. nana on coarse soil. Even though these findings indicate that the native F. ovina is the best alternative with regard to establishment of a native species in the greenhouse, these patterns may not always be expected in nature due to other environmental factors, like wind. However the findings in this study indicate that using native species is the best alternative in alpine ecosystem restoration.

Effective population size (Ne) is a fundamental concept within biology and can be defined as the size of an ideal Wright-Fisher population in which the rate of genetic drift is the same as in the observed population. Natural populations are not ideal so that Ne is often < Nc. A low Ne can lead to inbreeding depression and less adaptability in a population, thus it is essential to know Ne for threatened populations. Ne can be estimated using genetic or demographic data. In this study four different genetic estimators (LDNE, ONeSAMP, MLNE and CoNe) and one demographic estimator were compared using data from a natural house sparrow metapopulation. How Ne related to Nc was also examined. All four genetic estimators seemed to be upwardly biased, however, LDNE often produced estimates in the expected range (Ne<N) and thus appeared to be less biased. To understand how characteristics of natural populations may affect the rate of genetic drift it is important to examine what influence the Ne/Nc-ratio. Thus, I investigated whether population characteristics such as population size, sex ratio, immigration rate, variance in population size and population growth rate explained the variation in the Ne/N ratio for the different genetic estimators. A general result was that the immigration rate had a positive effect on the Ne/Nc-ratio. The apparent upward bias of genetic Ne estimates and the positive effect of immigration rate on Ne/Nc-ratio suggest that gene flow between subpopulations within the study metapopulation was of significant importance for the rate of genetic drift. Genetic estimators of Ne seem like promising tools. However, if no knowledge of the ecology of the population in question exists, Ne should be interpreted cautiously. When assumptions underlying estimators are violated this can lead to erroneous conclusions about genetic processes in the population. 

Question: How does nutrient addition and seeding affect revegetation of seed plants, and are the effects differing among the stages of the regeneration pathway? Location: Two roads restored in 2002, located in Hjerkinn firing range, in lower alpine zone of Dovrefjell, Norway.Methods: Abundance of species and functional types (dwarf shrubs, forbs and graminoids) in four stages of the regeneration pathway (seed rain, seed bank, field seedlings and established vegetation) was recorded seven years after road reconstruction in treatment plots (with nutrient addition, nutrient + seed addition and no treatment). Results: The graminoid Deschampsia cespitosa dominated the vegetation and seed rain in fertilized plots, while the seeded Festuca rubra still dominated the seeded + fertilized plots. The germinable seed bank was lowest in the seeded + fertilized treatment, while the control plots had the highest number of seedlings germinating in the field. Dwarf shrubs had a high germination rate in the field, despite low rates in the seed rain and seed bank. The highest rate of dwarf shrub seedlings was in control plots, while the frequency of dwarf shrubs in the established vegetation increased with nutrient addition. Forbs had species specific responses.Conclusions: Both treatments that included nutrients were dominated by graminoids, with a higher vegetation cover and frequency of dwarf shrubs than the control plots. While graminoids are the most efficient seed producers, they are less able to germinate and survive as seedlings. Dwarf shrubs accounted for a high proportion of germinating seedlings in the field, but the low frequencies of dwarf shrubs in the established control plot vegetation suggest either low seedling survival or an ongoing successional change. It remains to be revealed if the high recruitment of dwarf shrubs in the control plots will speed up the establishment of the typical dwarf shrub cover similar to the surrounding vegetation and hereby indicate that unassisted recovery is the fastest way to restore alpine dwarf shrub heath.

Sik (Coregonus lavaretus) dominerte i littorale- og littorale habitater. Røyr hadde størst utbredelse i profundale habitater. Artene viste betydelig næringsoverlapp.

The ongoing global warming is especially pronounced in the arctic, and it is therefore important to investigate the effect of these changes on arctic ecosystems. In this study the Snow bunting (Plectrophenax nivalis) breeding in Spitsbergen, Svalbard was used as a model species to investigate how the climatic variations are affecting avian reproduction. Both big scale climatic parameters and local weather variables were included in an analysis of how these factors affected snow bunting breeding success. It turned out that both big scale and local variables were important. Locale temperature and wind was important for time off breeding. Temperature, precipitation, winter North Atlantic Oscillation (NAOw) and winter Arctic Oscillation (AOw) were important for number of fledged chicks, and wind and air pressure were important for growth rate.