Coextinctions dominate future vertebrate losses from climate and land use change

Although theory identifies coextinctions as a main driver of biodiversity loss, their role at the planetary scale has yet to be estimated. We subjected a global model of interconnected terrestrial vertebrate food webs to future (2020-2100) climate and land-use changes. We predict a 17.6% (+/- 0.16% SE) average reduction of local verte-brate diversity globally by 2100, with coextinctions increasing the effect of primary extinctions by 184.2% (+/- 10.9% SE) on average under an intermediate emissions scenario. Communities will lose up to a half of ecological interactions, thus reducing trophic complexity, network connectance, and community resilience. The model reveals that the extreme toll of global change for vertebrate diversity might be of secondary importance com-pared to the damages to ecological network structure.Peer reviewe

EVALUATING STRENGTH QUALITIES OF ATHLETES USING RELATIONSHIPS BETWEEN JUMP PROTOCOLS

Understanding the relationships between jump assessments may provide information of an athlete’s strength qualities. Elastic Utilisation Ratio (EUR) is calculated between countermovement jump (CMJ) and squat jump (SQJ) height, and is suggested to describe the stretch-shortening cycle ability of an athlete. Yet, knowledge of what constitutes a typical EUR range for an athlete remains unclear. The purpose of this study was to assess jump performance and the EUR of athletes from two sports (soccer and distance runners) using a portable forceplate. SQJ and CMJ heights were highly correlated (r>.90). Linear regression and standard error of estimate statistics were then used to estimate CMJ height and derive an expected EUR range. It was concluded, those athletes outside this predicted EUR range would benefit from specific training

LATERALITY AND ITS EFFECT ON LOWER EXTREMITY MUSCULOSKELETAL STIFFNESS IN MALE SOCCER PLAYERS AND TRACK RUNNERS

The purpose of this study was to determine the influence of laterality on lower extremity stiffness in healthy soccer players and track runners. Eight soccer players aged 15 to 17 years, and eight track runners, aged from 18 to 25 years performed a battery of tests (Single and double legged continuous straight and bent-legged jumping, and running) to determine lower extremity musculoskeletal stiffness. All participants were injury free at the time of testing. Statistical tests of the various all kinetic measures revealed that the track runners were asymmetrical in their musculoskeletal performance qualities, whereas, the soccer players displayed symmetry. Future research should examine lower extremity symmetry in an older group of soccer players, and the development of a training program to alter lower extremity stiffness into a typical range

Spot the match – wildlife photo-identification using information theory

BACKGROUND: Effective approaches for the management and conservation of wildlife populations require a sound knowledge of population demographics, and this is often only possible through mark-recapture studies. We applied an automated spot-recognition program (I(3)S) for matching natural markings of wildlife that is based on a novel information-theoretic approach to incorporate matching uncertainty. Using a photo-identification database of whale sharks (Rhincodon typus) as an example case, the information criterion (IC) algorithm we developed resulted in a parsimonious ranking of potential matches of individuals in an image library. Automated matches were compared to manual-matching results to test the performance of the software and algorithm. RESULTS: Validation of matched and non-matched images provided a threshold IC weight (approximately 0.2) below which match certainty was not assured. Most images tested were assigned correctly; however, scores for the by-eye comparison were lower than expected, possibly due to the low sample size. The effect of increasing horizontal angle of sharks in images reduced matching likelihood considerably. There was a negative linear relationship between the number of matching spot pairs and matching score, but this relationship disappeared when using the IC algorithm. CONCLUSION: The software and use of easily applied information-theoretic scores of match parsimony provide a reliable and freely available method for individual identification of wildlife, with wide applications and the potential to improve mark-recapture studies without resorting to invasive marking techniques

Predicting the Timing and Magnitude of Tropical Mosquito Population Peaks for Maximizing Control Efficiency

The transmission of mosquito-borne diseases is strongly linked to the abundance of the host vector. Identifying the environmental and biological precursors which herald the onset of peaks in mosquito abundance would give health and land-use managers the capacity to predict the timing and distribution of the most efficient and cost-effective mosquito control. We analysed a 15-year time series of monthly abundance of Aedes vigilax, a tropical mosquito species from northern Australia, to determine periodicity and drivers of population peaks (high-density outbreaks). Two sets of density-dependent models were used to examine the correlation between mosquito abundance peaks and the environmental drivers of peaks or troughs (low-density periods). The seasonal peaks of reproduction (r) and abundance () occur at the beginning of September and early November, respectively. The combination of low mosquito abundance and a low frequency of a high tide exceeding 7 m in the previous low-abundance (trough) period were the most parsimonious predictors of a peak's magnitude, with this model explaining over 50% of the deviance in . Model weights, estimated using AICc, were also relatively high for those including monthly maximum tide height, monthly accumulated tide height or total rainfall per month in the trough, with high values in the trough correlating negatively with the onset of a high-abundance peak. These findings illustrate that basic environmental monitoring data can be coupled with relatively simple density feedback models to predict the timing and magnitude of mosquito abundance peaks. Decision-makers can use these methods to determine optimal levels of control (i.e., least-cost measures yielding the largest decline in mosquito abundance) and so reduce the risk of disease outbreaks in human populations

The First Australians grew to a population of millions, much more than previous estimates

We know it is more than 60,000 years since the first people entered the continent of Sahul — the giant landmass that connected New Guinea, Australia and Tasmania when sea levels were lower than today. But where the earliest people moved across the landscape, how fast they moved, and how many were involved, have been shrouded in mystery. Our latest research, published today shows the establishment of populations in every part of this giant continent could have occurred in as little as 5,000 years. And the entire population of Sahul could have been as high as 6.4 million people. This translates to more than 3 million people in the area that is now modern-day Australia, far more than any previous estimate

Socio-economic predictors of environmental performance among African nations

Socio-economic changes in Africa have increased pressure on the continent's ecosystems. Most research investigating environmental change has focused on the changing status of specific species or communities and protected areas, but has largely neglected the broad-scale socio-economic conditions underlying environmental degradation. We tested national-scale hypotheses regarding the socioeconomic predictors of ecosystem change and degradation across Africa, hypothesizing that human density and economic development increase the likelihood of cumulative environmental damage. Our combined environmental performance rank includes national ecological footprint, proportional species threat, recent deforestation, freshwater removal, livestock density, cropland coverage, and per capita emissions. Countries like Central African Republic, Botswana, Namibia, and Congo have the best relative environmental performance overall. Structural equation models indicate that increasing population density and overall economic activity (per capita gross domestic product corrected for purchasing-power parity) are the most strongly correlated with greater environmental degradation, while greater wealth inequality (Gini index) correlates with better environmental performance. This represents the first Africa-scale assessment of the socio-economic correlates of environmental degradation, and suggests that dedicated family planning to reduce population growth, and economic development that limits agricultural expansion (cf. intensification) are needed to support environmental sustainability.Peer reviewe

Evaluating the Relative Environmental Impact of Countries

Environmental protection is critical to maintain ecosystem services essential for human well-being. It is important to be able to rank countries by their environmental impact so that poor performers as well as policy ‘models’ can be identified. We provide novel metrics of country-specific environmental impact ranks – one proportional to total resource availability per country and an absolute (total) measure of impact – that explicitly avoid incorporating confounding human health or economic indicators. Our rankings are based on natural forest loss, habitat conversion, marine captures, fertilizer use, water pollution, carbon emissions and species threat, although many other variables were excluded due to a lack of country-specific data. Of 228 countries considered, 179 (proportional) and 171 (absolute) had sufficient data for correlations. The proportional index ranked Singapore, Korea, Qatar, Kuwait, Japan, Thailand, Bahrain, Malaysia, Philippines and Netherlands as having the highest proportional environmental impact, whereas Brazil, USA, China, Indonesia, Japan, Mexico, India, Russia, Australia and Peru had the highest absolute impact (i.e., total resource use, emissions and species threatened). Proportional and absolute environmental impact ranks were correlated, with mainly Asian countries having both high proportional and absolute impact. Despite weak concordance among the drivers of environmental impact, countries often perform poorly for different reasons. We found no evidence to support the environmental Kuznets curve hypothesis of a non-linear relationship between impact and per capita wealth, although there was a weak reduction in environmental impact as per capita wealth increases. Using structural equation models to account for cross-correlation, we found that increasing wealth was the most important driver of environmental impact. Our results show that the global community not only has to encourage better environmental performance in less-developed countries, especially those in Asia, there is also a requirement to focus on the development of environmentally friendly practices in wealthier countries