The thrifty phenotype hypothesis proposes reduced nutrition alters the trajectory of development of metabolic regulatory systems to produce a phenotype better fitted to an environment of decreased later-life nutrient availability. Because organisms have physiological mechanisms for coping with poor nutrition, they may have sociobehavioral mechanisms as well. Aggressive behavior, especially in the context of feeding competition, may be advantageous in such environments. There could be an association between aggression and intrauterine growth restriction (IUGR), which can result from low maternal food intake during pregnancy. The main hypotheses of this study are [1] IUGR offspring demonstrate higher rates of aggressive behavior and [2] IUGR offspring attain higher ranks. Behavioral observations were conducted on 22 juvenile baboons (Papio sp., ages 3-5 yrs) living in groups. Male IUGR (n = 4) and female IUGR (n = 5) were offspring of mothers fed 70% the same feed eaten by control (CTR) mothers in pregnancy and lactation. CTR males (n = 8) and CTR females (n = 5) were offspring of mothers fed ad libitum. Some authorities recommend this moderate level of dietary restriction for health and longevity. Offspring have not experienced dietary restriction since weaning. IUGR, compared to CTR, showed significantly increased rates of aggressive behavior, especially threat displays. Differences were more dramatic in males than in females. IUGR baboons performed the affiliative display behaviors lipsmack and chatter at elevated rates too, perhaps to counteract the effects of increased aggressive displays. IUGR females exhibited increased rates of stereotypical chewing behavior, while IUGR males exhibited decreased rates of play behavior, possibly indicating elevated anxiety levels. There was only limited support for condition-based differences in rank. Elevated rates of aggression in IUGR baboons may reflect an aggressive behavioral phenotype that enhances fitness by improving access to resources. Alternatively, they could be a non-adaptive result of neurodevelopment with a potentially negative impact on fitness. Unraveling the dynamic relationship between experiences and development is essential for understanding how phenotypes are formed. This will improve the ability of mothers to assess benefits of different nutritional strategies, leading to healthier individuals not just during growth and development, but throughout life.

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Introducing automated vehicles in to traffic withhuman drivers, human behavior prediction is essential to obtainoperation safety. In this study, a human behavior estimationmodel has been developed. The estimations are based on aHidden Markov Model (HMM) using observations to determinethe driving style of surrounding vehicles. The model is trainedusing two different methods: Baum Welch training and Viterbitraining to improve the performance. Both training methods areevaluated by looking at time complexity and convergence. Themodel is implemented with and without training and tested fordifferent driving styles. Results show that training is essentialfor accurate human behavior prediction. Viterbi training is fasterbut more noise sensitive compared to Baum Welch training. Also,Viterbi training produces good results if training data reflects oncurrently observed driver, which is not always the case. BaumWelch training is more robust in such situations. Lastly, BaumWelch training is recommended to obtain operation safety whenintroducing automated vehicles into traffic. / N ̈ar automatiserade fordon introduceras itrafiken och beh ̈over interagera med m ̈anskliga f ̈orare ̈ar det vik-tigt att kunna f ̈orutsp ̊a m ̈anskligt beteende. Detta f ̈or att kunnaerh ̊alla en s ̈akrare trafiksituation. I denna studie har en modellsom estimerar m ̈anskligt beteende utvecklats. Estimeringarna ̈ar baserade p ̊a en Hidden Markov Model d ̈ar observationeranv ̈ands f ̈or att best ̈amma k ̈orstil hos omgivande fordon itrafiken. Modellen tr ̈anas med tv ̊a olika metoder: Baum Welchtr ̈aning och Viterbi tr ̈aning f ̈or att f ̈orb ̈attra modellens prestanda.Tr ̈aningsmetoderna utv ̈arderas sedan genom att analysera derastidskomplexitet och konvergens. Modellen ̈ar implementerad medoch utan tr ̈aning och testad f ̈or olika k ̈orstilar. Erh ̊allna resultatvisar att tr ̈aning ̈ar viktigt f ̈or att kunna f ̈orutsp ̊a m ̈anskligtbeteende korrekt. Viterbi tr ̈aning ̈ar snabbare men mer k ̈ansligf ̈or brus i j ̈amf ̈orelse med Baum Welch tr ̈aning. Viterbi tr ̈aningger ̈aven en bra estimering i de fall d ̊a observerad tr ̈aningsdataavspeglar f ̈orarens k ̈orstil, vilket inte alltid ̈ar fallet. BaumWelch tr ̈aning ̈ar mer robust i s ̊adana situationer. Slutligenrekommenderas en estimeringsmodell implementerad med BaumWelch tr ̈aning f ̈or att erh ̊alla en s ̈aker k ̈orning d ̊a automatiseradefordon introduceras i trafiken / Kandidatexjobb i elektroteknik 2020, KTH, Stockholm

<p>Hur beter sig skärpiplärkor (Anthus petrosus) när de försvarar reviret mot en inkräktare under häckning? Eskalerar de aggressivitet olika eller har de en gemensam strategi? Påverkas beteendet av häckningsfas? Kan använd tid säga något om motivation att försvara revir? För att besvara dessa frågor placerades en burhållen artfrände av endera kön i etablerade revir. I studien mättes ägnad tid åt olika aggressiva beteenden, vilka hade klassats och graderats beroende av styrkan i hoten. Resultatet visade att alla hanar eskalerar aggression på ett likartat sätt och ägnade i medeltal lika lång tid åt olika nivåer. Individuella skillnader förekom dock då några individer eskalerade lite snabbare men det tolkades inte som ökad motivation att försvara revir. Tiden de ägnade åt de olika nivåerna varierade inte beroende av häckningsfas.</p> / <p>How do rock pipits (Anthus petrosus) behave when they defend a territory against an intruder during their breeding season? Do they escalate aggression differently, or do they have a common strategy? Does breeding phase influence the behavior? May used time tell something about the motivation to defend the territory? To answer these questions a caged conspecific of either sex were placed in established territories. In the study the time was measured of each different aggressive behavior, which had been classified into levels according to the intensity of the threat. The results showed that all males escalated aggression in the same way and devoted similar lengths of time to the different levels. Some individual differences occurred as a few individuals escalated somewhat rapidly, however, this was not interpreted as increased motivation to defend the territory. The time they devoted to different levels did not vary depending on breeding phase.</p>

Call number: LD2668 .T4 1986 M46 / Master of Science / Biology