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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2005.03.040 Byline: Michael A. Cant Abstract: The recent development of reproductive skew (RS) theory shows striking parallels with that of parent-offspring conflict (POC) theory a decade earlier. In particular, the concept of 'battleground' and 'resolution' models in POC theory is equally relevant to RS theory. The battleground of conflict in POC and RS has been defined by different constraints (which I term 'optimization' and 'group stability' constraints, respectively). This distinction is not inherent but arises simply because POC models assume that the fitness benefits of an increasing share of resource show diminishing returns, whereas skew models assume a linear relation between reproductive share and fitness. Incorporating diminishing returns into skew models reveals a simple and almost wholly neglected explanation for reproductive sharing. Models of POC have moved on from simply defining the battleground to consider how conflict within it is resolved. The development of analogous models for RS theory is at a relatively early stage. In particular, more work is needed to understand the manner and extent to which overt aggression can mediate reproductive control. Lessons learned from attempts to test POC theory can help guide tests of RS theory, and provide information on both the nature of the battleground over reproduction and the mechanism by which conflicts are resolved. Author Affiliation: Department of Zoology, University of Cambridge Article History: Received 26 November 2004; Revised 9 February 2005; Accepted 15 March 2005 Article Note: (miscellaneous) MS. number: RV-56

An evolutionary stable strategy (ESS) model of reproductive partitioning that supports the likelihood of indiscriminate infanticide is presented. The ESS model predicts circumstances when infanticide will become stable and characterizes its effects on the pattern of reproduction within the group. Through this model, it was shown that indiscriminate destruction of the young will not change the level of reproduction. However, it may influence the reproductive behavior of the dominant animals and the subordinates

A model for the evolution of the reproductive skew that considers the effect of brood size on the inclusive fitness of dominants and subordinates is described. This model forecasts that reproductive skew will increase with relatedness between breeders. It also describes the dominant's optimal response to a second breeder that exaggerates the relationship between skew and relatedness. The model suggests that dominants should produce more young when breeding with related in contrast with unrelated subordinates.

Research conducted in Chironomus plumosus midges find that the mating success depends on the fluctuating asymmetry in the male characters, and the success of symmetrical male is due to his improved aerobatic ability. Male Chironomus plumosus, successful at acquiring mates, show lower levels of fluctuating asymmetry in the length of wing than their rivals. Small males are found to be more successful in acquiring mates.

Abstract Background All animals are anatomically constrained in the number of discrete call types they can produce. Recent studies suggest that by combining existing calls into meaningful sequences, animals can increase the information content of their vocal repertoire despite these constraints. Additionally, signalers can use vocal signatures or cues correlated to other individual traits or contexts to increase the information encoded in their vocalizations. However, encoding multiple vocal signatures or cues using the same components of vocalizations usually reduces the signals' reliability. Segregation of information could effectively circumvent this trade-off. In this study we investigate how banded mongooses (Mungos mungo) encode multiple vocal signatures or cues in their frequently emitted graded single syllable close calls. Results The data for this study were collected on a wild, but habituated, population of banded mongooses. Using behavioral observations and acoustical analysis we found that close calls contain two acoustically different segments. The first being stable and individually distinct, and the second being graded and correlating with the current behavior of the individual, whether it is digging, searching or moving. This provides evidence of Marler's hypothesis on temporal segregation of information within a single syllable call type. Additionally, our work represents an example of an identity cue integrated as a discrete segment within a single call that is independent from context. This likely functions to avoid ambiguity between individuals or receivers having to keep track of several context-specific identity cues. Conclusions Our study provides the first evidence of segmental concatenation of information within a single syllable in non-human vocalizations. By reviewing descriptions of call structures in the literature, we suggest a general application of this mechanism. Our study indicates that temporal segregation and segmental concatenation of vocal signatures or cues is likely a common, but so far neglected, dimension of information coding in animal vocal communication. We argue that temporal segregation of vocal signatures and cues evolves in species where communication of multiple unambiguous signals is crucial, but is limited by the number of call types produced.

Survey in 10 provinces shows variability in composting trends with 60 percent of population in British Columbia being provided with composting facility to Newfoundland and Labrador having little or no municipal composting. With 350 composting facilities in 2007, most being small dealing with leaf and yard wastes, trend of growth in number of these facilities is being seen particularly in Alberta and Ontario.

Behavioral mechanisms for avoiding inbreeding are common in the natural world and are believed to have evolved as a response to the negative consequences of inbreeding. However, despite a fundamental role in fitness, we have a limited understanding of the cues that individuals use to assess inbreeding risk, as well as the extent to which individual inbreeding behavior is repeatable. We used piecewise structural equation modeling of 24 years of data to investigate the causes and consequences of within- versus extra-group paternity in banded mongooses. This cooperatively breeding mammal lives in tight-knit social groups that often contain closely related opposite-sex breeders, so inbreeding can be avoided through extra-group mating. We used molecular parentage assignments to show that, despite extra-group paternity resulting in outbred offspring, within-group inbreeding occurs frequently, with around 16% litters being moderately or highly inbred. Additionally, extra-group paternity appears to be plastic, with females mating outside of their social group according to individual proxies (age and immigration status) and societal proxies (group size and age) of within-group inbreeding risk but not in direct response to levels of within-group relatedness. While individual repeatability in extra-group paternity was relatively low, female cobreeders showed high repeatability, suggesting a strong constraint arising from the opportunities for extra-group mating. The use of extra-group paternity as an inbreeding avoidance strategy is, therefore, limited by high costs, opportunity constraints, and the limited reliability of proxies of inbreeding risk. [ABSTRACT FROM AUTHOR]

The primary purpose of the study was to identify and explore the impact of the global COVID-19 crisis on consumers' purchase behaviour in the context of South Africa. A nonprobability convenience sampling technique was used to collect data using a structured questionnaire. The quantitative data analysis of the responses of 200 respondents reveals that the perception of the COVID-19 crisis significantly influences economic crisis and household consumption at P<0.05 and financial difficulties at the P<0.10 level. Moreover, analysis of variance (ANOVA) tests showed that responses on the perception of the COVID-19 crisis, economic crisis and household consumption are not statistically different across different income groups. However, responses to financial difficulties are statistically different across different income groups. It indicates that people with lower income levels have more financial challenges than those with higher levels of income and need to adapt their purchase behaviour accordingly to make ends meet. The study makes a contribution to the existing literature related to the pandemic and consumer behaviour. In addition, academics, marketers and decision-makers will benefit from a better understanding regarding consumer behaviour during the time of a crisis or pandemic. [ABSTRACT FROM AUTHOR]

Animal groups are heterogeneous assemblages of individuals with differing fitness interests, which may lead to internal conflict over investment in group territorial defence. Differences between individuals may lead to different behavioural responses to intergroup conflict, particularly between the sexes. These potential impacts have been little studied.We used social network analysis to investigate the impact of simulated intergroup conflicts on social relationships in groups of wild banded mongooses Mungos mungo, in which intergroup fights are more costly for males than females. We predicted that social cohesion (specifically male‐to‐male and female‐to‐male grooming) would increase after conflict, and aggression would decrease, to minimize conflict between the sexes.Simulated intergroup conflicts were performed by exposing banded mongoose groups to scents, 'war cry' playbacks, and live intruders from a rival group. All grooming and aggression interactions between individuals were recorded, and grooming and aggression social networks were created for the 2 days preceding a simulated intergroup conflict (pre‐conflict network) and the 2 days after (post‐conflict network).We found no evidence of an increase in social cohesion after simulated conflicts, measured as grooming eigenvector centrality. Male‐to‐male, male‐to‐female and female‐to‐male grooming strength decreased after simulated intrusions compared to female‐to‐female grooming strength. However, male–female aggression decreased in intrusion trials compared to other interaction types, consistent with the hypothesis that intergroup encounters reduce the level of intragroup conflict between males and females. Males were more affected socially by intergroup encounters than females, which may be because they are investing in defence rather than internal relationships.Focusing on individual relationship changes, using social network analysis, can reveal changes in the directionality of behaviour in response to intergroup encounters, and highlight how individual responses to conflict may scale up to affect social networks and, potentially, group performance. This study highlights the importance of studying both group‐level behaviours and individual relationships to more fully understand responses to intergroup encounters. [ABSTRACT FROM AUTHOR]

Small businesses are widely considered to be valuable assets for any economy. This sector contributes up to 20 percent of the South African economy and holds the key to improving the quality of life of residents who live in informal settlements, as small businesses have the ability to create jobs. It is therefore imperative for the government to implement strategies to assist South Africa's small, medium, and micro enterprise (SMME) owners with legal processes in order to create a more enabling operating environment in townships. [ABSTRACT FROM AUTHOR]

As technology develops and students are being exposed to it from the day they are born, it necessitates a change in the way they receive tuition. This study explores the relevance of traditional personal teaching theories in a technologically advanced educational environment. Self-completion questionnaires were issued to lecturers, ranging from junior lecturers to senior professors, of a leading South African university in order to determine their teaching philosophy and theory. Four basic theories of teaching (transfer, shaping, traveling, and growing) were unpacked and elements thereof were included in the questionnaires. It is clear from the study that critical thinking is the preferred teaching theory of lecturers. It is recommended that uniform approaches to teaching be adopted by lecturers in order to improve students' learning and success. [ABSTRACT FROM AUTHOR]