Infanticide and infant defence by males--modelling the conditions in primate multi-male groups

Infanticide by primate males was considered rare if groups contain more than one adult male because, owing to lower paternity certainty, a male should be less likely to benefit from infanticide. Guided by recent evidence for strong variation of infanticide in primate multi-male groups, we modelled the conditions for when infanticide should occur for a group with a resident and an immigrant male. Setting the parameters (e.g. infant mortality, reduction of interbirth interval, life-time reproductive success, genetic representation) to fit the conditions most commonly found in nature, we develop a game-theoretic model to explore the influence of age and dominance on the occurrence of infanticide and infant defence. Male age strongly impacts the likelihood of an attack which is modified by the father's defence. If the new male is dominant he is likely to attack under most circumstances whereas a subordinate male will only attack if the father does not defend. These model scenarios fit the conditions under which infanticide is known to occur in primate multi-male groups and offer an explanation why infanticide is common in some multi-male groups and rare in others. Overall, the benefits for infanticidal males are strongly governed by a reduced interbirth interval while advantages via improved genetic representation in the gene pool contribute but a minor fraction

Demography and Life Histories of Sympatric Patas Monkeys, Erythrocebus patas, and Vervets, Cercopithecus aethiops, in Laikipia, Kenya

Mortality patterns are thought to be strong selective forces on life history traits, with high adult mortality and low immature mortality favoring early and rapid reproduction. Patas monkeys (Erythrocebus patas) have the highest potential rates of population increase for their body size of any haplorhine primate because they reproduce both earlier and more often. We report here 10 yr of comparative demographic data on a population of patas monkeys and a sympatric population of vervet monkeys (Cercopithecus aethiops), a closely related species differing in aspects of social system, ecology, and life history. The data reveal that 1) adult female patas monkeys have significantly higher mortality than adult female vervets; 2) infant mortality in patas monkeys is relatively low compared to the norm for mammals because it is not significantly different from that of adult female patas monkeys; and 3) infant mortality is significantly higher than adult female mortality in vervets. For both species, much of the mortality could be attributed to predation. An epidemic illness was also a major contributor to the mortality of adult female patas monkeys whereas chronic exposure to pathogens in a cold and damp microenvironment may have contributed to the mortality of infant vervets. Both populations experienced large fluctuations during the study period. Our results support the prediction from demographic models of life history evolution that high adult mortality relative to immature mortality selects for early maturation

The impact of expiration date tracking software in grocery stores : A task-technology fit review of information systems used for date-checking in grocery stores

Each year, 1.3 billion tons of food produced for human consumption are lost or go to waste globally throughout the food supply chain (FSC). Increasing the efficiency of the entire FSC is an essential action in achieving food security for the global population, which includes reducing the amount of food lost and wasted. This thesis aims to contribute with rich insight into if and how contemporary information systems in grocery stores, which are part of the FSC, are supporting expiration date tracking and if they are contributing to reducing food waste. The study was carried out as a case study in three grocery stores, applying the task-technology fit model as its theoretical framework to guide the study and analyze the empirical results. The study found that the expiration date tracking systems in the grocery stores supported them in tracking expiration dates considering the measurements of task-technology fit since they sufficiently support and fulfill the needs of the users’ tasks, but that there is still room for improvement. The study also found that, according to the users’ perceptions, the grocery stores using expiration date tracking systems were able to prevent more food waste when using the systems in comparison to if they would not have been used.

The impact of expiration date tracking software in grocery stores : A task-technology fit review of information systems used for date-checking in grocery stores

Each year, 1.3 billion tons of food produced for human consumption are lost or go to waste globally throughout the food supply chain (FSC). Increasing the efficiency of the entire FSC is an essential action in achieving food security for the global population, which includes reducing the amount of food lost and wasted. This thesis aims to contribute with rich insight into if and how contemporary information systems in grocery stores, which are part of the FSC, are supporting expiration date tracking and if they are contributing to reducing food waste. The study was carried out as a case study in three grocery stores, applying the task-technology fit model as its theoretical framework to guide the study and analyze the empirical results. The study found that the expiration date tracking systems in the grocery stores supported them in tracking expiration dates considering the measurements of task-technology fit since they sufficiently support and fulfill the needs of the users’ tasks, but that there is still room for improvement. The study also found that, according to the users’ perceptions, the grocery stores using expiration date tracking systems were able to prevent more food waste when using the systems in comparison to if they would not have been used.

Kan en applikation förändra våra val av livsmedel för en grönare planet? : En studie om ICA:s “Mitt Klimatmåls” beteendepåverkan genom persuasive design & technology

Food production in Sweden accounts for almost one third of all greenhouse gas emissions created by humans. Sustainability has therefore become a hot topic and several companies and organizations are developing different types of applications to get people to change their behavior in a direction towards a better environment. This is done, among other things, through Persuasive Design and Technology, which is technology developed to change people's behavior. ICA has a web application, “Mitt klimatmål”, that wants to inspire and engage people to make more sustainable choices when it comes to food purchases. In this paper, a qualitative study was conducted in the form of an experiment with interviews to find out if this application can change the behavior of the users, and also to find out what improvement factors exist and which could motivate the users even more. The results contribute to an increased understanding of the impact a system of this type has on its users and the types of functions that affect users the most.Matproduktionen i Sverige står för nästan en tredjedel av allt växthusgasutsläpp som skapas av människor. Hållbarhet har därför blivit ett hett ämne och flera företag och organisationer utvecklar olika typer av applikationer för att få människor att ändra deras beteende i en riktning mot en bättre miljö. Detta görs bl.a. genom Persuasive Design och Technology, vilket är teknik utvecklat för att förändra människors beteende. ICA har en webbapplikation, “Mitt klimatmål”, som vill inspirera och engagera människor till att göra mer hållbara val när det kommer till köp av livsmedel. I denna uppsats genomfördes en kvalitativ studie i form av ett experiment med intervjuer för att dels ta reda på om denna applikation kan förändra användarnas beteende, och dels för att ta reda på vilka förbättringsfaktorer som finns och som skulle kunna motivera användarna ännu mer. Resultaten bidrar till en ökad förståelse för vilken inverkan ett system av denna typ har på sina användare och vilka typer av funktioner som påverkar användarna mest