Recent and Projected Increases in Atmospheric CO2 Concentration Can Enhance Gene Flow between Wild and Genetically Altered Rice (Oryza sativa)

Although recent and projected increases in atmospheric carbon dioxide can alter plant phenological development, these changes have not been quantified in terms of floral outcrossing rates or gene transfer. Could differential phenological development in response to rising CO2 between genetically modified crops and wild, weedy relatives increase the spread of novel genes, potentially altering evolutionary fitness? Here we show that increasing CO2 from an early 20th century concentration (300 µmol mol−1) to current (400 µmol mol−1) and projected, mid-21st century (600 µmol mol−1) values, enhanced the flow of genes from wild, weedy rice to the genetically altered, herbicide resistant, cultivated population, with outcrossing increasing from 0.22% to 0.71% from 300 to 600 µmol mol−1. The increase in outcrossing and gene transfer was associated with differential increases in plant height, as well as greater tiller and panicle production in the wild, relative to the cultivated population. In addition, increasing CO2 also resulted in a greater synchronicity in flowering times between the two populations. The observed changes reported here resulted in a subsequent increase in rice dedomestication and a greater number of weedy, herbicide-resistant hybrid progeny. Overall, these data suggest that differential phenological responses to rising atmospheric CO2 could result in enhanced flow of novel genes and greater success of feral plant species in agroecosystems

Nutritional correlates of koala persistence in a low-density population

It is widely postulated that nutritional factors drive bottom-up, resource-based patterns in herbivore ecology and distribution. There is, however, much controversy over the roles of different plant constituents and how these influence individual herbivores and herbivore populations. The density of koala (Phascolarctos cinereus) populations varies widely and many attribute population trends to variation in the nutritional quality of the eucalypt leaves of their diet, but there is little evidence to support this hypothesis. We used a nested design that involved sampling of trees at two spatial scales to investigate how leaf chemistry influences free-living koalas from a low-density population in south east New South Wales, Australia. Using koala faecal pellets as a proxy for koala visitation to trees, we found an interaction between toxins and nutrients in leaves at a small spatial scale, whereby koalas preferred trees with leaves of higher concentrations of available nitrogen but lower concentrations of sideroxylonals (secondary metabolites found exclusively in eucalypts) compared to neighbouring trees of the same species. We argue that taxonomic and phenotypic diversity is likely to be important when foraging in habitats of low nutritional quality in providing diet choice to tradeoff nutrients and toxins and minimise movement costs. Our findings suggest that immediate nutritional concerns are an important priority of folivores in low-quality habitats and imply that nutritional limitations play an important role in constraining folivore populations. We show that, with a careful experimental design, it is possible to make inferences about populations of herbivores that exist at extremely low densities and thus achieve a better understanding about how plant composition influences herbivore ecology and persistence.IW and WF received a grant from New South Wales (NSW) Department of Environment, Climate Change & Water

Indirect effects of species interactions on habitat provisioning

Species that shelter in a biogenic habitat can influence their refugia and, in turn, play an essential role in shaping local patterns of biodiversity. Here we explore a positive feedback loop between the provisioning rate of habitat-forming branching corals and their associated fishes and show how interactions between two groups of fish—the planktivorous damselfish and predatory hawkfish—altered the feedback. A field experiment confirmed that skeletal growth of branching coral (genus Pocillopora) increased substantially with increasing numbers (biomass) of resident fishes, likely because they greatly increased the interstitial concentrations of nutrients. Because there is a positive relationship between colony size and number (biomass) of associated fishes (primarily damselfishes in the Family Pomacentridae), a structure–function feedback loop exists in which increasing numbers of damselfish enhance coral growth and larger corals host greater abundances (and species richness) of fish. However, interactions between damselfishes and arc-eye hawkfish, Paracirrhites arcatus, a largely solitary resident, can disrupt this positive feedback loop. Field surveys revealed a marked pattern of fish occupancy related to coral size: Pocillopora colonies of sufficient size to host fish (>40 cm circumference) had either groups of damselfish or an arc-eye hawkfish; only larger colonies (>75 cm) were occupied by both the damselfish and hawkfish. Subsequent short- and long-term experiments revealed that on intermediate-sized Pocillopora colonies, arc-eye hawkfish prevented the establishment of damselfish by suppressing their recruitment. The demographic consequences to the host coral were substantial; in a 1-year-long experiment, intermediate-size Pocillopora occupied by hawkfish grew at half the rate of corals that hosted groups of damselfish. These findings indicate that: (1) species which occupy a biogenic habitat can enhance the provisioning rate of their habitat; (2) such positive feedbacks between community structure and ecosystem function can be disrupted by a strong interactor; (3) even substantial consequences on ecosystem processes that arise can be difficult to discern

Sensitivity for Change Analyses of the Patient-Reported Outcomes in Obesity (PROS) Questionnaire: A Prospective Cohort Study

Pål André Hegland,1 Ronette L Kolotkin,2– 4 John Roger Andersen1,4 1Faculty of Health and Social Sciences, Western Norway University of Applied Sciences, Førde, Norway; 2Department of Family Medicine and Community Health, Duke University School of Medicine, Durham, NC, USA; 3Quality of Life Consulting, PLLC, Durham, NC, USA; 4Centre of Health Research, Førde Hospital Trust, Førde, NorwayCorrespondence: Pål André Hegland, Faculty of Health and Social Sciences, Western Norway University of Applied Sciences, Svanehaugvegen 1, Førde, 6812, Norway, Tel +47 90697135, Email [email protected]: Many patients seeking bariatric surgery experience reduced health-related quality of life (HRQOL). A simple clinical tool, the Patient-Reported Outcomes in Obesity (PROS), was developed to address patients’ HRQOL concerns during clinical consultations and facilitate meaningful dialogue. The present study aims to explore its sensitivity to change.Patients and Methods: A prospective study of patients undergoing bariatric surgery was conducted. The patients responded to items on the PROS and the Obesity-related Problems Scale (OP) before surgery and three, 12 and 24 months after surgery. Longitudinal mixed-effects models were applied to estimate the change in PROS and OP scores over time.Results: Thirty-eight patients were included. A significant change over time was detected for the PROS with the largest effect size at 24 months (effect size − 1.34, p ˂ 0.001), while the corresponding effect size for the OP was − 1.32 (p ˂ 0.001). In all items of the PROS, the majority of patients responded not bothered at 24 months. The items physical activity, pain, sleep and self-esteem showed the largest change in the percentage of patients reporting not bothered from baseline to 24 months after surgery.Conclusion: The PROS is sensitive to change over time and may be used as a brief, easy to administer tool to facilitate a conversation about obesity-specific quality of life in clinical consultations.Keywords: health-related quality of life, Patient-Reported Outcomes in Obesity, PROS, patient-centered follow-up, bariatric surger

Climate change impacts on pollination

Climate change will pose diverse challenges for pollination this century. Identifying and addressing these challenges will help to mitigate impacts, and avoid a scenario whereby plants and pollinators are in the ‘wrong place at the wrong time’