Female–female aggression : structure of interaction and outcome in loggerhead sea turtles

Aggressive behaviour between females of the same species is not widely documented, particularly in marine vertebrates. During a 3 yr in-water survey at the temperate loggerhead sea turtle Caretta caretta breeding area of Zakynthos, Greece, female–female interactions comprised 4% of all female loggerhead sighting events (n = 60 out of 1449 events). Male–female interactions comprised an additional 4% of sighting events, while 92% were of solitary females. The structure of interactions was analysed for 58 of these sighting events, each lasting an average of 3.4 min (SD ± 1) and comprising a total of 3.1 h observation time. We found that interactions involved ritualized escalation in behaviour from passive threat displays (e.g. head–tail circling) to aggressive combat (e.g. sparring). We suggest that circling individuals evaluate opponent size, sparring individuals test opponent strength, and that the positioning of the prehensile tail signals motivational intent to either escalate or abort. The presence of intruder females triggered a passive response in 100% of events involving basking and swimming turtles (n = 19); although residents resting on the seabed only responded on 69% of occasions (n = 27), their response was almost 4 times more likely to escalate to one of aggression. Our results suggest that certain sites may be preferentially sought after and defended by sea turtles.

Using climatic suitability thresholds to identify past, present and future population viability

Often climatic niche models predict that any change in climatic conditions will impact species abundance or distribution. However, the accuracy of models that just incorporate climatic information to predict future species habitat use is widely debated. Alternatively, environmental conditions may simply need to be above some minimum threshold of climatic suitability, at which point, other factors drive population size. Using the example of nesting sites of loggerhead sea turtles (Caretta caretta) in the Mediterranean (n = 105), we developed climatic niche models to examine whether a climatic suitability threshold could be identified as a climatic indicator in order for large populations of a widespread species to exist. We then assessed the climatic suitability of sites above and below this threshold in the past (∼1900) and future (∼2100). Most large sites that are currently above the climatic threshold were above the threshold in the past and future, particularly when future nesting seasonality shifted to start 1–2 months earlier. Our analyses highlight the importance of future phenological shifts for maintaining suitability. Our results provide a positive outlook for sea turtle conservation, suggesting that climatic conditions may remain suitable in the future at sites that currently support large nesting populations. Our study also provides an alternative way of interpreting the outputs of climatic niche models, by generating a threshold as an index of a minimum climatic suitability required to sustain large populations. This type of approach offers the possibility to benefit from information provided by climate-driven models, while reducing their inherent uncertainties.

International strategy: is it meeting the challenge?

The paper proposes an IS process model comprising inputs, development, outputs and a feedback loop based on performance measurement and its interpretation. The feedback impacts on the inputs and development components. Inputs are comprised of market information. human resources, diversity, value creation and host country environmental factors. Development includes preparation and learning. planning and scrutinising partnerships. anticipating impacts of globalisation and experience effects. Outputs comprise structure, scope of operations, target countries. facility location and positioning. Performance interpretation explains rapid and major changes in IS outputs, such as structure and business unit portfolios, whilst process complexity explains observed output similarities for organisations reacting to similar inputs and suggests an evolutionary approach in their determination.

Uncontrolled face recognition by individual stable neural network

There usually exist diverse variations in face images taken under uncontrolled conditions. Most previous work on face recognition focuses on particular variations and usually assume the absence of others. Such work is called controlled face recognition. Instead of the ‘divide and conquer’ strategy adopted by controlled face recognition, this paper presents one of the first attempts directly aiming at uncontrolled face recognition. The solution is based on Individual Stable Neural Network (ISNN) proposed in this paper. ISNN can map a face image into the so-called Individual Stable Space (ISS), the feature space that only expresses personal characteristics, which is the only useful information for recognition. There are no restrictions for the face images fed into ISNN. Moreover, unlike many other robust face recognition methods, ISNN does not require any extra information (such as view angle) other than the personal identities during training. These advantages of ISNN make it a very practical approach for uncontrolled face recognition. In the experiments, ISNN is tested on two large face databases with vast variations and achieves the best performance compared with several popular face recognition techniques.

Information system strategy for promoting demolition project management

Building demolition has been undergoing evolutionary development in its technologies for several decades. In order to achieve a high level of demolition material reuse and recycling, new management approaches are also necessitated, in particular in conjunction with the applications of information technologies. The development of an information system for demolition project management is an impactful strategy to support various demolition activities including waste exchange, demolition visualization, and demolition method selection and evaluation. This paper aims to develop a framework of an integrated information system for building demolition project demolition decision-making and waste minimization. The components of this information system and their interactions are demonstrated through a specifical demolition project.

International strategy : is it meeting the challenge?

International strategy (IS) is the approach by which an organisation's capabilities and resources are directed to generate value utilising the global market's opportunities (and risks). Many of the largest multinationals invest significant resources in their IS, however, the literature does not offer any substantive model for the process. This paper presents a model of the IS process which comprises two parts, the first part is made up of inputs, development and outputs and the second comprises a feedback loop based on organisational performance measurement and its interpretation which impacts on the first part stages of inputs and development. The content of the model is explained and justified using examples of practice. Inputs are comprised of market information, human resources, diversity and value creation and host country environmental factors. Development is comprised of preparation and learning, planning and scrutinising partnerships, anticipating impacts of globalisation, anticipating impacts of technology, location, experience effects, planning competencies, planning for cost effectiveness, scenario planning, planning structures and operations, leadership and ethics. Outputs are comprised of structure, scope of operations, target countries, facility location and positioning. Performance interpretation explains rapid and major changes in IS outputs, such as structure
and business unit portfolios, whilst process complexity explains observed output similarities for organisations reacting to similar inputs and suggests an evolutionary approach in their determination.

Sexual segregation in western grey kangaroos: testing alternative evolutionary hypotheses

In sexually dimorphic ungulates, sexual segregation is hypothesized to have evolved because of sex-specific differences in body size and/or reproductive strategies. We tested these alternative hypotheses in kangaroos, which are ecological analogues of ungulates. Kangaroos exhibit a wide range of body sizes, particularly among mature males, and so the effects of body size and sex can be distinguished. We tested predictions derived from these hypotheses by comparing the distribution of three sex–sex size classes of western grey kangaroos Macropus fuliginosus, in different habitats, and the composition of groups of kangaroos, across seasons. In accordance with the predation risk-reproductive strategy hypothesis, during the non-breeding season, females, which were more susceptible to predation than larger males, and were accompanied by vulnerable young-at-foot, were over-represented in secure habitats. Large males, which were essentially immune to predation, occurred more often than expected in nutrient-rich habitat, and small males, which faced competing demands of predator avoidance and feeding, were intermediate between females and large males in their distribution across habitats. During the breeding season, females continued to be over-represented in secure habitats when their newly emerged pouch young were most vulnerable to predation. All males occupied these same habitats to maximize their chances of securing mates. Consistent with the social hypotheses, groups composed of individuals of the same sex, irrespective of body size, were over-represented in the population during the non-breeding season, while during the breeding season all males sought females so that mixed-sex groups predominated. These results indicate that body size and reproductive strategies are both important, yet independent, factors influencing segregation in western grey kangaroos.

Individual stable space : an approach to face recognition under uncontrolled conditions

There usually exist many kinds of variations in face images taken under uncontrolled conditions, such as changes of pose, illumination, expression, etc. Most previous works on face recognition (FR) focus on particular variations and usually assume the absence of others. Instead of such a ldquodivide and conquerrdquo strategy, this paper attempts to directly address face recognition under uncontrolled conditions. The key is the individual stable space (ISS), which only expresses personal characteristics. A neural network named ISNN is proposed to map a raw face image into the ISS. After that, three ISS-based algorithms are designed for FR under uncontrolled conditions. There are no restrictions for the images fed into these algorithms. Moreover, unlike many other FR techniques, they do not require any extra training information, such as the view angle. These advantages make them practical to implement under uncontrolled conditions. The proposed algorithms are tested on three large face databases with vast variations and achieve superior performance compared with other 12 existing FR techniques.

Rethinking a learning environment strategy

I have committed a significant period of time (in my case five years) to the purpose development of learning environments, with the belief that it would improve the self-actualisation and self-motivation of students and teachers alike. I consider it important to record and measure performance as we progressed toward such an outcome. Education researchers and practitioners alike, in the higher (university/tertiary) education systems, are seeking among new challenges to engage students and teachers in learning (James, 2001). However, studies to date show a confusing landscape littered with a multiplicity of interpretations and terms, successes and failures. As the discipline leader of the Information Technology, Systems and Multimedia (ITSM) Discipline, Swinburne University of Technology, Lilydale, I found myself struggling with this paradigm. I also found myself being torn between what presents as pragmatic student learning behaviour and the learner-centred teaching ideal reflected in the Swinburne Lilydale mission statement. The research reported in this folio reflects my theory and practice as discipline leader of the ITSM Discipline and the resulting learning environment evolution during the period 1997/8 to 2003. The study adds to the material evidence of extant research through firstly, a meta analysis of the learning environment implemented by the ITSM Discipline as recorded in peer reviewed and published papers; and secondly, a content analysis of student learning approaches, conducted on data reported from a survey of ‘learning skills inventory’ originally conducted by the ITSM Discipline staff in 2002. In 1997 information and communication technologies (ICT) were beginning to provide plausible means for electronic distribution of learning materials on a flexible and repeatable basis, and to provide answers to the imperative of learning materials distribution relating to an ITSM Discipline new course to begin in 1998. A very short time frame of three months was available prior to teaching the course. The ITSM Discipline learning environment development was an evolutionary process I began in 1997/8 initially from the requirement to publish print-based learning guide materials for the new ITSM Discipline subjects. Learning materials and student-to-teacher reciprocal communication would then be delivered and distributed online as virtual learning guides and virtual lectures, over distance as well as maintaining classroom-based instruction design. Virtual here is used to describe the use of ICT and Internet-based approaches. No longer would it be necessary for students to attend classes simply to access lecture content, or fear missing out on vital information. Assumptions I made as discipline leader for the ITSM Discipline included, firstly, that learning should be an active enterprise for the students, teachers and society; secondly, that each student comes to a learning environment with different learning expectations, learning skills and learning styles; and thirdly, that the provision of a holistic learning environment would encourage students to be self-actualising and self-motivated. Considerable reading of research and publications, as outlined in this folio, supported the update of these assumptions relative to teaching and learning. ITSM Discipline staff were required to quickly and naturally change their teaching styles and communication of values to engage with the emergent ITSM Discipline learning environment and pedagogy, and each new teaching situation. From a student perspective such assumptions meant students needed to move from reliance upon teaching and prescriptive transmission of information to a self-motivated and more self-actualising and reflective set of strategies for learning. In constructing this folio, after the introductory chaperts, there are two distinct component parts; • firstly, a Descriptive Meta analysis (Chapter Three) that draws together several of my peer reviewed professional writings and observations that document the progression of the ITSM Discipline learning environment evolution during the period 1997/8 to 2003. As the learning environment designer and discipline leader, my observations and published papers provide insight into the considerations that are required when providing an active, flexible and multi-modal learning environment for students and teachers; and • secondly, a Dissertation (Chapter Four), as a content analysis of a learning skills inventory data collection, collected by the ITSM Discipline in the 2002 Swinburne Lilydale academic year, where students were encouraged to complete reflective journal entries via the ITSM Discipline virtual learning guide subject web-site. That data collection included all students in a majority of subjects supported by the ITSM Discipline for both semesters one and two 2002. The original purpose of the journal entries was to have students reflectively involved in assessing their learning skills and approaches to learning. Such perceptions were tested using a well-known metric, the ‘learning skills inventory’ (Knowles, 1975), augmented with a short reflective learning approach narrative. The journal entries were used by teaching staff originally and then made available to researchers as a desensitised data in 2003 for statistical and content analysis relative to student learning skills and approaches. The findings of my research support a view of the student and teacher enculturation as utilitarian, dependent and pragmatically self-motivated. This, I argue, shows little sign of abatement in the early part of the 21st Century. My observation suggests that this is also independent of the pedagogical and educational philosophy debate or practice as currently presented. As much as the self-actualising, self-motivated learning environment can be justified philosophically, the findings observed from this research, reported in this folio, cannot. Part of the reason for this originates from the debate by educational researchers as to the relative merits of liberal and vocational philosophies for education combined with the recent introduction of information and communication technologies, and commodification of higher education. Challenging students to be participative and active learners, as proposed by educationalists Meyers and Jones (1993), i.e. self-motivated and self-actualising learners, has proved to be problematic. This, I will argue, will require a change to a variable/s (not yet identified) of higher education enculturation on multiple fronts, by students, teachers and society in order to bridge the gap. This research indicates that tertiary educators and educational researchers should stop thinking simplistically of constructivist and/or technology-enabled approaches, students learning choices and teachers teaching choices. Based on my research I argue for a far more holistic set of explanations of student and staff expectations and behaviour, and therefore pedagogy that supports those expectations.

Long-term species, sexual and individual variations in foraging strategies of fur seals revealed by stable isotopes in whiskers

Background: Individual variations in the use of the species niche are an important component of diversity in trophic interactions. A challenge in testing consistency of individual foraging strategy is the repeated collection of information on the same individuals.

Methodology/Principal Findings: The foraging strategies of sympatric fur seals (Arctocephalus gazella and A. tropicalis) were examined using the stable isotope signature of serially sampled whiskers. Most whiskers exhibited synchronous delta C-13 and delta N-15 oscillations that correspond to the seal annual movements over the long term (up to 8 years). delta C-13 and delta N-15 values were spread over large ranges, with differences between species, sexes and individuals. The main segregating mechanism operates at the spatial scale. Most seals favored foraging in subantarctic waters (where the Crozet Islands are located) where they fed on myctophids. However, A. gazella dispersed in the Antarctic Zone and A. tropicalis more in the subtropics. Gender differences in annual time budget shape the seal movements. Males that do not perform any parental care exhibited large isotopic oscillations reflecting broad annual migrations, while isotopic values of females confined to a limited foraging range during lactation exhibited smaller changes. Limited inter-individual isotopic variations occurred in female seals and in male A. tropicalis. In contrast, male A. gazella showed large inter-individual variations, with some males migrating repeatedly to high-Antarctic waters where they fed on krill, thus meaning that individual specialization occurred over years.

Conclusions/Significance: Whisker isotopic signature yields unique long-term information on individual behaviour that integrates the spatial, trophic and temporal dimensions of the ecological niche. The method allows depicting the entire realized niche of the species, including some of its less well-known components such as age-, sex-, individual- and migration-related changes. It highlights intrapopulation heterogeneity in foraging strategies that could have important implications for likely demographic responses to environmental variability.

Acceleration data reveal the energy management strategy of a marine ectotherm during reproduction

1. Maintaining a high and stable body temperature is often critical for female ectotherms during reproduction. Yet this strategy may be energetically costly, and therefore challenging, during this period of already high-energy demand. 2. Here, the 6-week deployment of tri-axial accelerometers (n = 6) on a marine ectotherm, the loggerhead turtle (Caretta caretta), reproducing at the northern limit of the species’ breeding range (i.e. in a thermally dynamic environment) revealed the behavioural mechanisms underlying its energy management strategy during the breeding season. 3. The estimated activity levels of female loggerheads using overall dynamic body acceleration (ODBA) were high during the breeding season, suggesting that marine turtles may not be able to remain inactive for long periods in the same manner as terrestrial ectotherms, because of the thermally dynamic nature of their environment. 4. However, activity levels were not constant throughout the season, being impacted by both ambient water temperature and female reproductive status. In cold water at the beginning of the nesting season, high levels of activity suggested that females behaviourally thermoregulated by seeking out warm water patches along the shoreline. Interactions with male turtles (courtship and/or avoidance) may also explain this high level of activity. As sea temperatures warmed up and the amount of energy devoted to reproduction probably increased, the turtles spent more time resting during long sequential flat-bottomed dives, and reduced any unnecessary locomotory activity. 5. Turtles may therefore adjust their activity patterns in response to seasonal variations in abiotic (i.e. ambient temperature) and biotic (i.e. reproductive status) factors. This may help minimize activity-linked metabolic rate and maximize reproductive output over a season while breeding in thermally dynamic environments. 6. A mechanistic model gave support to these empirical results. The model revealed that actively maintaining high and stable body temperature is of clear benefit to female turtles at temperate breeding sites. While energetically costly, such active thermoregulatory behaviour may speed up egg maturation, allowing turtles to initiate nesting earlier in the season, and hence maximize reproductive output.

Bioinspired strategy for tuning thermal stability of PVA via hydrogen-bond crosslink

Although many approaches have been employed to enhance thermal stability of PVA, developing a facile and effective strategy remains highly attractive. Herein, we demonstrate a highly effective approach to strikingly improve thermal stability of PVA by selecting the types of multiamines molecules to tune the hydrogen-bond crosslink density. Results show that only adding 0.5 wt% of 2,4,5,6-tetraaminopyrimidine can make the initial degradation temperature (Ti) and maximum degradation temperature (Tmax) of PVA increase by ~55 °C and 98 °C due to the formation of 3D physically H-bond crosslinked network, resulting in superior thermal stability property to those of PVA nanocomposites. Moreover, thermal stability strongly depends on the H-bond crosslink density, and Ti and Tmax basically obey the linear hydrogen-bond relations despite some deviations. This work opens up a novel biological methodology for creating thermally stable polymeric materials.

Subnanometer molybdenum sulfide on carbon nanotubes as a highly active and stable electrocatalyst for hydrogen evolution reaction

Electrochemically splitting water for hydrogen evolution reaction (HER) has been viewed as a promising approach to produce renewable and clean hydrogen energy. However, searching for cheap and efficient HER electrocatalysts to replace the currently used Pt-based catalysts remains an urgent task. Herein, we develop a one-step carbon nanotube (CNT) assisted synthesis strategy with CNTs' strong adsorbability to mediate the growth of subnanometer-sized MoS(x) on CNTs. The subnanometer MoS(x)-CNT hybrids achieve a low overpotential of 106 mV at 10 mA cm(-2), a small Tafel slope of 37 mV per decade, and an unprecedentedly high turnover frequency value of 18.84 s(-1) at η = 200 mV among all reported non-Pt catalysts in acidic conditions. The superior performance of the hybrid catalysts benefits from the presence of a higher number of active sites and the abundant exposure of unsaturated S atoms rooted in the subnanometer structure, demonstrating a new class of subnanometer-scale catalysts.

Mating success and body condition not related to foraging specializations in male fur seals

Individual specialization is widespread among wild populations. While its fitness consequences are central in predicting the ecological and evolutionary trajectories of populations, they remain poorly understood. Long-term individual foraging specializations occur in male Antarctic (Arctocephalus gazella) and Australian (A. pusillus doriferus) fur seals. Strong selective pressure is expected in these highly dimorphic and polygynous species, raising the question of the fitness payoffs associated with different foraging strategies. We investigated the relationship between individual isotopic niche (a proxy of foraging specialization), body size and condition, and an index of reproductive success (harem size) in territorial males. Individuals varied greatly in their skin and fur isotopic values reflecting a range of foraging strategies within the two populations. However, in both species, isotopic niche was not correlated to body size, condition or mating success (R (2)/ρ < 0.06). Furthermore, no foraging niche was predominant in either species, which would have indicated a substantial long-term fitness benefit of a particular strategy via a higher survival rate. These results suggest that the fitness consequences of a foraging strategy depend not only on the quality of prey and feeding habitat but also on an individual's hunting efficiency and skills.

Transmissible cancers in an evolutionary context.

Cancer is an evolutionary and ecological process in which complex interactions between tumour cells and their environment share many similarities with organismal evolution. Tumour cells with highest adaptive potential have a selective advantage over less fit cells. Naturally occurring transmissible cancers provide an ideal model system for investigating the evolutionary arms race between cancer cells and their surrounding micro-environment and macro-environment. However, the evolutionary landscapes in which contagious cancers reside have not been subjected to comprehensive investigation. Here, we provide a multifocal analysis of transmissible tumour progression and discuss the selection forces that shape it. We demonstrate that transmissible cancers adapt to both their micro-environment and macro-environment, and evolutionary theories applied to organisms are also relevant to these unique diseases. The three naturally occurring transmissible cancers, canine transmissible venereal tumour (CTVT) and Tasmanian devil facial tumour disease (DFTD) and the recently discovered clam leukaemia, exhibit different evolutionary phases: (i) CTVT, the oldest naturally occurring cell line is remarkably stable; (ii) DFTD exhibits the signs of stepwise cancer evolution; and (iii) clam leukaemia shows genetic instability. While all three contagious cancers carry the signature of ongoing and fairly recent adaptations to selective forces, CTVT appears to have reached an evolutionary stalemate with its host, while DFTD and the clam leukaemia appear to be still at a more dynamic phase of their evolution. Parallel investigation of contagious cancer genomes and transcriptomes and of their micro-environment and macro-environment could shed light on the selective forces shaping tumour development at different time points: during the progressive phase and at the endpoint. A greater understanding of transmissible cancers from an evolutionary ecology perspective will provide novel avenues for the prevention and treatment of both contagious and non-communicable cancers.