Two behavioural traits promote fine-scale species segregation and moderate hybridisation in a recovering sympatric fur seal population

Background: In systems where two or more species experience secondary contact, behavioural factors that regulate interspecific gene flow may be important for maintaining species boundaries and reducing the incidence of hybridisation. At subantarctic Macquarie Island, two species of fur seal breed in close proximity to one another, hybridise at very high levels (up to 21% of hybrid pups are born annually), yet retain discrete gene pools. Using spatial and genetic information collected for pups and adults over twelve years, we assessed two behavioural traits – interannual site fidelity and differences in habitat use between the species - as possible contributors to the maintenance of this species segregation. Further, we explored the breakdown of these traits in pure-species individuals and hybrids. Results: We found virtually complete spatial segregation of the parental species, with only one exception; a single territory that contained adults of both species and also the highest concentration of hybrid pups. The spatial distribution of each species was closely linked to habitat type (pebbled vs boulder beaches), with members of each species breeding almost exclusively on one type or the other but hybrids breeding on both or at the junction between habitats. Inter-annual site fidelity was high for both sexes of pure-species adults, with 66% of females and all males returning to the same territory or a neighbouring one in different years. An important consequence for pure females of breeding on the 'wrong' habitat type, and thus in a heterospecific aggregation, was the production of hybrid pups. Low habitat fidelity of hybrid females facilitated bi-directional backcrossing, resulting in more diverse hybrid offspring. Conclusion: In a disturbed system where two sympatric fur seal species breed in close proximity, discrete gene pools are retained by extremely fine-scale and strong spatial segregation of the species. Two behavioural traits were found to be important in maintaining this stable population structure, and habitat type was a strong indicator of where species locate and a potentially powerful predictor of future directions of hybridisation. A direct consequence of the breakdown of this trait was the production of hybrid offspring, which may have severe implications if hybrids have reduced fitness.Melanie L Lancaster, Simon D Goldsworthy and Paul Sunnuck

Experimentation at the interface of fluvial geomorphology, stream ecology and hydraulic engineering and the development of an effective, interdisciplinary river science

One ‘2020 vision’ for fluvial geomorphology is that it sits alongside stream ecology and hydraulic engineering as a key element of an integrated, interdisciplinary river science. A challenge to this vision is that scientists from these three communities may approach problems from different perspectives with different questions and have different methodological outlooks. Refining interdisciplinary methodology is important in this context, but raises a number of issues for geomorphologists, ecologists and engineers alike. In particular, we believe that it is important that there is greater dialogue about the nature of mutually-valued questions and the adoption of mutually-acceptable methods. As a contribution to this dialogue we examine the benefits and challenges of using physical experimentation in flume laboratories to ask interdisciplinary questions. Working in this arena presents the same challenges that experimental geomorphologists and engineers are familiar with (scaling up results, technical difficulties, realism) and some new ones including recognizing the importance of biological processes, identifying hydraulically meaningful biological groups, accommodating the singular behaviour of individuals and species, understanding biological as well as physical stimuli, and the husbandry and welfare of live organisms. These issues are illustrated using two examples from flume experiments designed (1) to understand how the movement behaviours of aquatic insects through the near-bed flow field of gravelly river beds may allow them to survive flood events, and (2) how an understanding of the way in which fish behaviours and swimming capability are affected by flow conditions around artificial structures can lead to the design of effective fish passages. In each case, an interdisciplinary approach has been of substantial mutual benefit and led to greater insights than discipline-specific work would have produced. Looking forward to 2020, several key challenges for experimentalists working on the interface of fluvial geomorphology, stream ecology and hydraulic engineering are identified

Person-environment congruence and the identity development of young adults: converging two theories of career development

According to Erik Erikson (1950), adolescents and young adults are highly engaged in the process of identity development with intentions to avoid a state of diffusion and role confusion. Several researchers (e.g., Bordin, 1990; Krumboltz, 1979; Lofquist & Dawis, 1991; Super, 1957) in the area of career development have attempted to explain how identity relates to the career selection process for young adults, all seeming to describe a similar construct, that of self identity. Perhaps the most popular theory of career development, HollandÂs (1959) theory, clarified the identity construct by Holland's Vocational Identity is first compared to Marcia's four ego identity statuses (Diffusion, Foreclosure, Moratorium, and Achieved), indicating a positive relationship to ego identity development. Second, person-environment (P-E) congruence was compared to Erikson's/Marcia's four identity statuses and Vocational Identity, revealing no relationship between the variables. However, strong relationships were apparent for P-E Congruence and well-being measures, including satisfaction with academic major, stability in academic major, and academic achievement. In further investigation of the identity formation process, identity variables were compared to measures of well-being. Using canonical correlation analysis, the first canonical function showed Vocational Identity as a strong indicator of well-being. Canonical correlation analysis was also used to compare measures of career development with Erikson's/Marcia's ego identity development. Results revealed a strong statistical relationship with the first canonical root, indicating Vocational Identity and career decision making both appear to be strongly related to the Achieved identity status. These findings further support the theoretical connection between ego identity and career development process. Considering limitations of the study, implications for theory and practice and recommendations for future research are provided. describing Vocational Identity as the possession of a clear and stable picture of oneÂs goals, interests, and talents. This study sought to clarify similarities between EriksonÂs theory of identity development and HollandÂs theory of vocational choice. To assess the relationship between identity formation and career development, 206 college students completed scales measuring ego identity formation, using MarciaÂs (1966) empirical representation of EriksonÂs theory, Vocational Identity, measures of congruence, measures of well-being, and Career Indecision

The laterality of the gallop gait in Thoroughbred racehorses

<div><p>Laterality can be observed as side biases in locomotory behaviour which, in the horse, manifest <i>inter alia</i> as forelimb preferences, most notably in the gallop. The current study investigated possible leading-leg preferences at the population and individual level in Thoroughbred racehorses (n = 2095) making halt-to-gallop transitions. Videos of flat races in the UK (n = 350) were studied to record, for each horse, the lead-leg preference of the initial stride into gallop from the starting stalls. Races from clockwise (C) and anti-clockwise (AC) tracks were chosen alternately at random to ensure equal representation. Course direction, horse age and sex, position relative to the inside rail and finishing position were also noted. On C courses, the left/right ratio was 1.15, which represents a significant bias to the left (z = –2.29, p = 0.022), while on AC courses it was 0.92 (z = 0.51, p = 0.610). In both course directions, there was no significant difference between winning horses that led with the left leading leg versus the right (C courses, z = –1.32, p = 0.19 and AC courses, z = –0.74, p = 0.46). Of the 2,095 horses studied 51.26% led with their L fore and 48.74% with their R, with no statistically significant difference (z = -1.16, p = 0.25). Therefore, there was no evidence of a population level motor laterality. Additionally, 22 male and 22 female horses were randomly chosen for repeated measures of leading leg preference. A laterality index was calculated for each of the 44 horses studied using the repeated measures: 22 exhibited right laterality (of which two were statistically significant) and 21 exhibited left laterality (eight being statistically significant); one horse was ambilateral. Using these data, left lateralized horses were more strongly lateralized on an individual level than the right lateralized horses (t = 2.28, p = 0.03, DF = 34) and mares were more left lateralized than males (t = 2.4, p = 0.03, DF = 19).</p></div

Curiosity Killed the M-Cat: an Examination of Illicit Drugs and Media

Using mainstream media communication theories, this article outlines different mechanisms by which media can impact on public perceptions of drugs and crime. The media can set the agenda and define public interest; frame issues through selection and salience; indirectly shape individual and community attitudes towards risk and norms; and feed into political debate and decision making. We demonstrate how the media can fulfill each of these roles by examining the so-called Miaow Miaow (Mephedrone) legal high ‘epidemic’, as reported in the United Kingdom news media from 2009-2010. In doing so we illustrate that by contributing to hysteria, exerting pressure for policy change and increasing curiosity in drug use, the media can have a potentially powerful impact on demand for drugs and public perceptions of illicit drugs and drugs policy.Sydney Institute of Criminology; School of Social Sciences at the University of Western Sydne

Toward autism recognition using hidden Markov models

Master of ScienceDepartment of Computing and Information SciencesDavid A. GustafsonThe use of hidden Markov models in autism recognition and analysis is investigated. More specifically, we would like to be able to determine a person's level of autism (AS, HFA, MFA, LFA) using hidden Markov models trained on observations taken from a subject's behavior in an experiment. A preliminary model is described that includes the three mental states self-absorbed, attentive, and join-attentive. Futhermore, observations are included that are more or less indicative of each of these states. Two experiments are described, the first on a single subject and the second on two subjects. Data was collected from one individual in the second experiment and observations were prepared for input to hidden Markov models and the resulting hidden Markov models were studied. Several questions subsequently arose and tests, written in Java using the JaHMM hidden Markov model tool- kit, were conducted to learn more about the hidden Markov models being used as autism recognizers and the training algorithms being used to train them. The tests are described along with the corresponding results and implications. Finally, suggestions are made for future work. It turns out that we aren't yet able to produce hidden Markov models that are indicative of a persons level of autism and the problems encountered are discussed and the suggested future work is intended to further investigate the use of hidden Markov models in autism recognition

Predicting the behavior of robotic swarms in discrete simulation

Doctor of PhilosophyDepartment of Computing and Information SciencesDavid GustafsonWe use probabilistic graphs to predict the location of swarms over 100 steps in simulations in grid worlds. One graph can be used to make predictions for worlds of different dimensions. The worlds are constructed from a single 5x5 square pattern, each square of which may be either unoccupied or occupied by an obstacle or a target. Simulated robots move through the worlds avoiding the obstacles and tagging the targets. The interactions between the robots and the robots and the environment lead to behavior that, even in deterministic simulations, can be difficult to anticipate. The graphs capture the local rate and direction of swarm movement through the pattern. The graphs are used to create a transition matrix, which along with an occupancy matrix, can be used to predict the occupancy in the patterns in the 100 steps using 100 matrix multiplications. In the future, the graphs could be used to predict the movement of physical swarms though patterned environments such as city blocks in applications such as disaster response search and rescue. The predictions could assist in the design and deployment of such swarms and help rule out undesirable behavior

Supercapacitor Degradation: Understanding Mechanisms of Cycling-Induced Deterioration and Failure of a Pseudocapacitor

Owing to a reputation for long lifetimes and excellent cycle stability, degradation in supercapacitors has largely been overlooked. In this work, we demonstrate that significant degradation in some commercial supercapacitors can in fact occur early in their life, leading to a rapid loss in capacitance, especially when utilized in full voltage range, high charge-discharge frequency applications. By using a commercial 300 F lithium-ion pseudocapacitor rated for 100,000 charge/discharge cycles as an example system, it is shown that a ∼96 % loss in capacitance over the first ∼2000 cycles is caused by significant structural and chemical change in the cathode active material (LiMn2O4, LMO). Multi-scale in-situ and ex-situ characterization, using a combination of X-ray computed tomography, Raman spectroscopy and X-ray photoelectron spectroscopy, shows that while minimal material loss (∼5.5 %), attributed to the dissolution of Mn2+, is observed, the primary mode of degradation is due to manganese charge disproportionation (Mn3+→Mn4++Mn2+) and its physical consequences (i. e. microstrain formation, particle fragmentation, loss of conductivity etc.). In contrast to prior understanding of LMO material degradation in battery systems, negligible contributions from cubic-to-tetragonal phase transitions are observed. Hence, as supercapacitors are becoming more widely utilized in real-world applications, this work demonstrates that it is vital to understand the mechanisms by which this family of devices change during their lifetimes, not just for lithium-ion pseudocapacitors, but for a wide range of commercial chemistries

Dispersal Evolution in Currents : spatial sorting promotes philopatry in upstream patches

Open Access via the Wiley Jisc Agreeement Funding – This work was funded by MarCRef, a collaboration between the Univ. of Aberdeen [grant number CF10434‐53] and Marine Scotland [grant number RG14645‐10], as part of Rebekka Allgayer's PhD program and Research Councils UK, Natural Environment Research Council, NE/T006935/1. The code for the model is available in a GitHub repository: .Peer reviewedPublisher PD