Laterality is linked to personality in the black-lined rainbowfish,Melanotaenia nigrans

Emotions such as fear in vertebrates are often strongly lateralised, that is, a single cerebral hemisphere tends to be dominant when processing emotive stimuli. Boldness is a measure of an individual’s propensity to take risks and it has obvious connections with fear responses. Given the emotive nature of this well-studied personality trait, there is good reason to suspect that it is also likely to be expressed in a single hemisphere. Here, we examined the link between laterality and boldness in wild and captive-reared rainbowfish, Melanotaenia nigrans. We found that fish from the wild were bolder than those from captivity, which might be a reflection of the differences in the level of predation pressure experienced by the two populations. Secondly, we found that non-lateralised fish were bolder than strongly lateralised fish. In addition, differences in boldness scores between left- and right-biased fish were revealed. We suggest that variation in cerebral lateralisation contributes to the persistence of individual differences in boldness scores in animal populations.     

A comparison of spatial learning and memory capabilities in intertidal gobies

For the majority of animals, the ability to orient in familiar locations is a fundamental part of life, and spatial memory allows individuals to remember key locations such as food patches, shelter, mating sites or areas regularly occupied by predators. This study determined if gobies collected from rocky platforms and sandy beaches differ in their ability to learn and memorise the locations of tide pools in a simulated rocky intertidal zone. Intertidal rock pool gobies show acute homing abilities and, therefore, should be expected to display superior learning and memory capabilities. In contrast, it is unlikely that natural selection would favour similar learning skills in sandy shore fishes because they simply shift back and forth with the tides. The learning abilities of gobies were tested using small replica rock platforms, containing four tide pools that retained varying depths of water at simulated low tide. Gobies were categorised as having learnt the task if they were able to consistently locate the tide pool that retained the most water at simulated low tide as the pool with the most favourable conditions. Rock pool species were able to locate the deepest pool to wait out low tide for ~95 % of the trials, while species from sandy shores were found in the deepest pool ~10 % of trials. Despite repeated stranding, sandy shore fish continued to follow the tide out. We propose that rock pool species memorised the location of rock pools during simulated high tide enabling them to relocate the best refuge for low tide.     

Collective fit perceptions: A multilevel investigation of person–group fit with individual‐level and team‐level outcomes

This study describes a multilevel examination of person–group (PG) fit perceptions in a sample of 1023 individuals working in 92 teams at a private sector R&D firm. Using confirmatory factor analysis and multilevel random coefficient modeling, we provide evidence that perceptions of team‐level collective fit are unique from aggregated individual‐level PG fit perceptions at the individual and team levels. We demonstrate that collective values‐based and abilities‐based fit perceptions showed unique and positive relationships with team cohesion, team efficacy, and team performance, after accounting for aggregated individual perceptions of PG fit. Results also demonstrate that cohesion partially mediates the relationship between collective fit and team performance. Cross‐level effects were also supported, indicating that collective fit explains additional variance in individual‐level outcomes, beyond individual‐level PG fit perceptions. The usefulness of employing a multilevel approach to studying PG fit is discussed. Copyright © 2014 John Wiley & Sons, Ltd.     

Changes in polybrominated diphenyl ether (PBDE) levels in cooked food

Food surveys for levels of toxic chemicals frequently report the levels on an uncooked basis. It is known that cooking may in some conditions decrease the amount of dioxins and related chemicals in food. Surveys of polybrominated diphenyl ether (PBDE) levels in food to date show data from uncooked food only. In this article, it was shown that broiling, with fat dripped from the foods reported here, ground beef, ground lamb, catfish, trout, and salmon, reduces the amount of PBDEs in these foods. This suggests that calculations of food intake need to take into consideration levels in the cooked food rather than in the uncooked food.     

Site fidelity and homing behaviour in intertidal fishes

The theory of ecological cognition poses that the brains and behaviour of animals are shaped by the environmental challenges they face in their everyday lives. Site fidelity and homing ability was tested for five species of intertidal rock pool fish by tagging and displacing them to new rock pools at various distances from their ‘home’ rock pools. Three of the species were rock pool specialists whilst the remaining two spend a small proportion of their life in rock pools during early ontogeny. The three specialists showed strong site fidelity with >50 % of individuals found in the same pool 42 days after tagging. In contrast, the non-specialist species showed low fidelity and poor homing abilities. Homing success in the rock pool specialists remained relatively stable as displacement distance increased. The effect of body size on homing ability was species dependent, with only one species showing a significantly greater tendency to home with increasing size.     

Applicability of Montreal Process Criterion 4 — soil and water conservation — to rangeland sustainability

SUMMARY

Criterion 4 of the Montreal Process addresses the conservation of soil and water resources as a way to assess the sustainability of a nation's forests. For the most part, the indicators under this criterion are relevant to rangelands. The area and percent of rangeland with significant soil erosion apply equally well to both biomes. Percent of streams with flow rates and timing outside its range of historical variation is also equally important, although a measure of proper functioning and condition may provide a better measure of the indicator. The area and percent of rangeland with diminished soil productive capability because of a loss of reduced organic matter or changed physical characteristics can be useful indicators locally and regionally.     

Novel molecular fingerprinting of marine avian diet provides a tool for gaining insights into feeding ecology

C₂₅ highly branched isoprenoids (HBIs) are produced by a relatively small number of diatom species, yet are common constituents of almost all marine environments. Previously, detection of HBIs in a few aquatic Arctic animals has indicated the potential use of these lipids for providing novel ecological information. In the current study, analysis of lipid extracts of livers from Leach’s storm petrel (Oceanodroma leucorhoa) and Brunnich’s guillemot (Uria lomvia) facilitated identification and quantification of HBI isomers. HBIs were found in the tissues of all specimens with clear differences in the abundances and distributions of individual HBI isomers both between Atlantic as well as Arctic birds. These differences are consistent with contrasting oceanographic regimes and suggests that regional differences in HBIs are reflected in the tissues of consumers. Tissue-specific assessment of HBI distributions has also revealed the presence of these lipids in muscle for the first time. This study represents the first report of HBI lipids in birds and provides evidence that these lipids are transferred across trophic levels and extends their potential use as chemical tracers beyond the ecology of aquatic organisms.     

Telomere dynamics in the Sydney rock oyster (<Emphasis Type="Italic">Saccostrea glomerata</Emphasis>): an investigation into the effects of age,tissue type,location and time of sampling

Telomere length has been purported as a biomarker for age and could offer a non-lethal method for determining the age of wild-caught individuals. Molluscs, including oysters and abalone, are the basis of important fisheries globally and have been problematic to accurately age. To determine whether telomere length could provide an alternative means of ageing molluscs, we evaluated the relationship between telomere length and age using the commercially important Sydney rock oyster (Saccostrea glomerata). Telomere lengths were estimated from tissues of known age individuals from different age classes, locations and at different sampling times. Telomere length tended to decrease with age only in young oysters less than 18 months old, but no decrease was observed in older oysters aged 2–4 years. Regional and temporal differences in telomere attrition rates were also observed. The relationship between telomere length and age was weak, however, with individuals of identical age varying significantly in their telomere length making it an imprecise age biomarker in oysters.     

Halton iterative partitioning: spatially balanced sampling via partitioning

A new spatially balanced sampling design for environmental surveys is introduced, called Halton iterative partitioning (HIP). The design draws sample locations that are well spread over the study area. Spatially balanced designs are known to be efficient when surveying natural resources because nearby locations tend to be similar. The HIP design uses structural properties of the Halton sequence to partition a resource into nested boxes. Sample locations are then drawn from specific boxes in the partition to ensure spatial diversity. The method is conceptually simple and computationally efficient, draws spatially balanced samples in two or more dimensions and uses standard design-based estimators. Furthermore, HIP samples have an implicit ordering that can be used to define spatially balanced over-samples. This feature is particularly useful when sampling natural resources because we can dynamically add spatially balanced units from the over-sample to the sample as non-target or inaccessible units are discovered. We use several populations to show that HIP sampling draws spatially balanced samples and gives precise estimates of population totals.