Ecology of<Emphasis Type="Italic"> Leptothorax</Emphasis> ants: impact of food,nest sites,and social parasites

In a long-term field manipulation, we demonstrate strong reactions of Leptothorax longispinosus ant colonies to food- and nest-site supplementation. Demographic and genetic responses varied over small geographic scales, and the two ecological factors interacted with the presence of the social parasite Protomognathus americanus. We conducted a 2×2 experiment in three blocks and found that the blocks, which were less than 100 m apart, reacted very differently to the treatments. Blocks differed in degree of polygyny, intranest relatedness, colony size, productivity, and sexual investment. Furthermore, these differences were associated with the presence of slave-making ants and the local availability of nest sites. Nest-site supplementation had a strong effect only in the site with the highest prevalence of social parasites, influencing there the density and investment patterns of colonies. L. longispinosus ants in the least parasitized area were strongly affected by both food- and nest-site supplementation. There, food supplementation led to a decrease in the number of queens per colony and consequently to an increase in intranest relatedness, while colonies in nest-site-supplemented areas invested fewer resources in males and produced a female-biased allocation ratio. By contrast, in a third block with a very low intracolonial relatedness, food supplementation induced an absolute and relative higher investment in males. We conclude that ecological factors influencing social organization in insect societies cannot be studied in isolation, because the interactions among factors produce far richer responses than any one variable.Communicated by L. Sundström     

Social relationships among adult female baboons (Papio cynocephalus) II. Variation in the quality and stability of social bonds

A growing body of evidence suggests that social bonds have adaptive value for animals that live in social groups. Although these findings suggest that natural selection may favor the ability to cultivate and sustain social bonds, we know very little about the factors that influence the quality or stability of social bonds. Here, we draw on data derived from a 16-year study of baboons living in seven different social groups in the Amboseli basin of Kenya to evaluate the quality and stability of social bonds among females. Our results extend previous analyses, which demonstrate that females form the strongest bonds with close maternal and paternal kin, age mates (who may be paternal kin), and females who occupy similar ranks but are not maternal relatives. Here we show that the same factors influence the quality and strength of social bonds. Moreover, the results demonstrate that the quality of social bonds directly affects their stability.     

The effects of castration, sex ratio and population density on social segregation and habitat use in Soay sheep

We analysed 16 years of census data gathered on the island of Hirta (archipelago of St. Kilda) to investigate the effects of castration, population density, sex ratio, season and group type on habitat use and social segregation of Soay sheep. From 1978 to 1980, 72 male lambs were castrated. We used this experiment to study how a change in reproductive status could affect sociality and habitat choice of these males. Males, females and castrates were all segregated outside the rutting season in autumn. Castrates were the least segregated from females in spring and summer but were most segregated from them during the pre-rut. The more equal the sex ratios, the higher was the degree of social segregation. The three sex classes used similar habitat types, namely, Holcus agrostis, Agrostis festuca and Calluna habitats. Holcus agrostis and Agrostis festuca were top- and second-ranked in female and castrate habitat use, while Holcus agrostis and Calluna were the two top habitat types used by rams. It is unclear why males included Calluna heath habitats, but it cannot be excluded that they might have shifted their use depending on forage availability. A lack in differences in habitat use between castrates and females suggests that body size differences alone cannot be the driving factor for habitat segregation in male and female Soay sheep and that there are reasons other than body size that could motivate reproductive males to use additional habitat types, such as Calluna heath. Although habitat use shifted from one habitat type to the next between low- and high-population-density years and between seasons, there was no clear link between population density and how different groups (male, female or castrate) used these areas. We discuss effects of reproductive status, population density and sex ratio on social segregation and habitat use and suggest that these factors need to be taken into account when investigating causes of sexual segregation in ungulates.     

Towards an ecological solution to the folivore paradox: patch depletion as an indicator of within-group scramble competition in red colobus monkeys (Piliocolobus tephrosceles)

A number of socioecological models assume that within-group food competition is either weak or absent among folivorous primates. This assumption is made because their food resources are presumed to be superabundant and evenly dispersed. However, recent evidence increasingly suggests that folivore group size is food-limited, that the primates prefer patchily distributed high-quality foods, and display some of the expected responses to within-group scramble competition. To investigate this apparent contradiction between theoretical models and recent empirical data, we examined the foraging behaviour of red colobus monkeys (Piliocolobus tephrosceles) in Kibale National Park, Uganda. We found that red colobus monkeys foraged in a manner that suggests they deplete patches of preferred foods: intake rate slowed significantly during patch occupancy while movement rate, an index of foraging effort, increased. Furthermore, patch occupancy was related to the size of the feeding group and the size of the patch. These results suggest that within-group scramble competition occurs, may limit folivore group size, and should be considered in models of folivore behavioural ecology.     

Prior experience with eggs laid by non-nestmate queens induces egg acceptance errors in ant workers

We studied the effect of prior experience to eggs laid by nestmate and non-nestmate queens on the acceptance of queen-laid eggs by worker wood ants, Formica fusca. We transferred eggs from a non-nestmate queen into colonies during early spring, when their own queen was recommencing egg laying. A few weeks later, workers from these “experienced” colonies accepted eggs of both familiar (44% acceptance) and unfamiliar (40%) non-nestmate queens much more than workers from control colonies (2%) that had only had previous contact with their own queen’s eggs. Thus, prior exposure to eggs laid by a non-nestmate queen induces much greater acceptance of all non-nestmate queen-laid eggs. Mechanistically, we hypothesize that exposure to eggs from several queens may increase acceptance by causing a highly permissive acceptance threshold of non-nestmate queen-laid eggs rather than by widening the template for acceptable queen-laid eggs. These novel results show that egg-discrimination behaviour in F. fusca is flexible and that workers respond to the diversity of eggs experienced in their colony.     

Population differentiation in female sex pheromone and male preferences in a solitary bee

Population differentiation in female mating signals and associated male preferences can drive reproductive isolation among segregated populations. We tested this assumption by investigating intraspecific variation in female sex pheromone and associated male odour preferences among distant populations in the solitary bee Colletes cunicularius (L.) by using quantitative gas chromatography and by performing field bioassays with synthetic blends of key sex pheromone compounds. We found significant differences in sex pheromone blends among the bee populations, and the divergence in odour blends correlated positively with geographic distance, suggesting that genetic divergence among distant populations can affect sex pheromone chemistry. Our behavioural experiments, however, demonstrate that synthetic copies of allopatric female sex pheromones were cross-attractive to patrolling males from distant populations, making reproductive isolation by non-recognition of mating signals among populations unlikely. Our data also show that patrolling male bees from different populations preferred odour types from allopatric populations at the two sites of bioassays. These male preferences are not expected to select for changes in the female sex pheromone, but may influence the evolution of floral odour in sexually deceptive orchids of the genus Ophrys that are pollinated by C. cunicularius males.     

Shopping online for children: Is safety a consideration?

Introduction: There has been a significant increase in online purchasing and product safety problems have been identified in e-commerce. This study examines consumer behavior and safety perceptions among parents purchasing child products online. Method: A mixed methods approach, including focus groups and a survey with parents, identified key characteristics and behaviors. Cluster analysis was used to determine different population segments (including “Informed,” “Uninformed,” and “Infrequent” consumer groups) based on their frequency of online shopping and search for product information. “Safe” and “Unsafe” behavior groups were identified related to their search for safety information on child products. Logistic regression analysis was used to study the effects of consumer type groups and demographic variables on the chances of being a safer consumer. Results: Findings indicate that child product safety considerations are not a priority for parents when shopping online. Only 62% of the survey respondents indicated that they search for information prior to buying a child product online, of which only 13% of the respondents noted that they search for information on product safety. Risky consumer behaviors were identified including the purchase of imitation products (counterfeit or knockoff products) and autonomous checks for product safety in lieu of safety standards. The logistic regression analysis found that being an “Uninformed Consumer” increases the odds of an individual being an “Unsafe Consumer” by 8.4 times (χ²(11) = 97.33, p < .001). Practical Applications: Design of a social marketing campaign that targets these different population segments to change perceptions and promote safe online purchasing is recommended.     

Building sustainable & resilient communities: a balancing of community capital

Working toward sustainable community is a complex task for communities especially given the ambiguous nature of implementing the concept of sustainable development. However, by working to understand the nature of community capital, administrators can begin to move beyond bottom line thinking toward a more comprehensive and collective view of community. This paper presents a theoretical framework that helps municipal decision makers begin collecting information they need to help them build sustainable and resilient communities.

Volcanic hazard warning system: Persistence and transferability

This study examines the normative functioning of the volcano warning system on the Island of Hawaii. The research seeks to identify the combination of factors, both environmental and social, which allows the system to operate with success. On the basis of the findings, several recommendations are offered for improving environmental hazard warning systems.     

Value Orientation and Forest Management: The Forest Health Debate

Among both forest practitioners and the general public, “forest health” has become an issue of contention. Whereas the debate over which treatments will best achieve healthy forests has been framed largely by the popular media and politicians as a struggle between industry and environmentalists, the views of the general public remain unexplored. Survey results from Oregon and Washington residents were used to assess the relationships between respondents’ self-described environmental or economic priorities and the following two variables: (1) acceptability of forest management practices and (2) perceived threats to forest health. Findings indicate that active management was generally accepted by a majority of respondents regardless of their environmental or economic orientation. Disagreement emerged, however, when the appropriateness of specific management practices within specific forest conditions was examined. Additionally, strong evidence was found for a relationship between self-described environmental or economic orientation and perceived threats to forest health. Those with an environmentally oriented viewpoint tended to perceive human-caused factors as the largest threats, whereas those with an economic orientation saw naturally occurring processes as the greatest threats. These findings suggest that the issue of contention is not active management per se. Rather, the major divisions in the forest health debate are defined by specific contexts and circumstances, as well as the management practices used.