How do native species respond to invaders? Mechanistic and trait-based perspectives

Adaptive responses of native species are important in enabling their persistence in the face of unprecedented biotic exchange. In the present paper I discuss how native species respond to invasive species both from a mechanistic and trait-based perspective. An earlier review by Strauss et al. (Ecol Lett 9:357–374, 2006) discussed a conceptual model of native species evolution in which the likelihood of an evolutionary response to an invader is dependent upon the strength of the selective pressure imposed (degree of variation in fitness between genotypes) and the adaptive capacity of the native (extent of pre-adaptation or genetic diversity). I aim to update and build upon this framework in light of new information on the interaction of phenotypic plasticity and evolutionary processes in adaptive responses of native species. Phenotypic plasticity can be a precursor to or an inhibitor of evolutionary responses and, under conditions of strong selection, phenotypic plasticity may enable adaptation where natives have a low evolutionary capacity. Based on current evidence, it is likely that phenotypic plasticity is the first front in native species adaptation, after which genetic changes occur via a genetic accommodation mechanism. Lastly, I review the literature on behavioural, morphological, physiological and life history trait changes of responding native species in light of this framework. Knowledge of the genetic and physiological underpinnings of adaptive responses in native species is limited and would aid in distinguishing the contributions of phenotypic plasticity and evolutionary change in future studies.13 page(s

Invertebrates on green roofs in Sydney

Includes bibliographical references.1. Introduction -- 2. Method -- 3. Results -- 4. Discussion -- 5. Conclusion -- 6. References -- 7. Appendix -- 8. Author guidelines.Rapid urbanisation is a leading cause of habitat loss, worldwide. Green roofs are thought to provide habitat benefits for a range of species, and support biodiversity conservation objectives in cities. Yet, this study is the first to properly quantify the added habitat value of green roofs over conventional bare rooftops. Drawing on classical ecological theory, this study assesses the factors which influence invertebrate diversity and composition on bare and green roofs in urban Sydney. Green roofs with at least 30% green cover are capable of supporting resident populations with up to twice the abundance and three times the variety of invertebrates compared to bare roofs. Bare roofs may provide a peculiar kind of habitat which favours predators or scavengers, but contain mainly transient individuals. The habitat value of green roofs is limited by immigration and resource provision, with large (>490 m2), structurally diverse, and well-connected green roofs hosting the greatest abundance and richness of invertebrates. Low-mobility taxa may be unable to colonise green roofs without human-mediated translocation. The findings of this study suggest that green roof implementation should consider: 1. landscape context, 2. roof size, 3. vegetation characteristics, 4. maintenance (including translocation of species of conservation concern or ecological value).Mode of access: World wide web1 online resource (83 pages) illustrations, ma

Effects of an Encapsulated Fruit and Vegetable Juice Concentrate on Obesity-Induced Systemic Inflammation: A Randomised Controlled Trial

Phytochemicals from fruit and vegetables reduce systemic inflammation. This study examined the effects of an encapsulated fruit and vegetable (F&V) juice concentrate on systemic inflammation and other risk factors for chronic disease in overweight and obese adults. A double-blinded, parallel, randomized placebo-controlled trial was conducted in 56 adults aged ≥40 years with a body mass index (BMI) ≥28 kg/m2. Before and after eight weeks daily treatment with six capsules of F&V juice concentrate or placebo, peripheral blood gene expression (microarray, quantitative polymerase chain reaction (qPCR)), plasma tumour necrosis factor (TNF)α (enzyme-linked immunosorbent assay (ELISA)), body composition (Dual-energy X-ray absorptiometry (DEXA)) and lipid profiles were assessed. Following consumption of juice concentrate, total cholesterol, low-density lipoprotein (LDL) cholesterol and plasma TNFα decreased and total lean mass increased, while there was no change in the placebo group. In subjects with high systemic inflammation at baseline (serum C-reactive protein (CRP) ≥3.0 mg/mL) who were supplemented with the F&V juice concentrate (n = 16), these effects were greater, with decreased total cholesterol, LDL cholesterol and plasma TNFα and increased total lean mass; plasma CRP was unchanged by the F&V juice concentrate following both analyses. The expression of several genes involved in lipogenesis, the nuclear factor-κB (NF-κB) and 5′ adenosine monophosphate-activated protein kinase (AMPK) signalling pathways was altered, including phosphomevalonate kinase (PMVK), zinc finger AN1-type containing 5 (ZFAND5) and calcium binding protein 39 (CAB39), respectively. Therefore, F&V juice concentrate improves the metabolic profile, by reducing systemic inflammation and blood lipid profiles and, thus, may be useful in reducing the risk of obesity-induced chronic disease

Effects of an Encapsulated Fruit and Vegetable Juice Concentrate on Obesity-Induced Systemic Inflammation: A Randomised Controlled Trial

Phytochemicals from fruit and vegetables reduce systemic inflammation. This study examined the effects of an encapsulated fruit and vegetable (F&V) juice concentrate on systemic inflammation and other risk factors for chronic disease in overweight and obese adults. A double-blinded, parallel, randomized placebo-controlled trial was conducted in 56 adults aged ≥40 years with a body mass index (BMI) ≥28 kg/m2. Before and after eight weeks daily treatment with six capsules of F&V juice concentrate or placebo, peripheral blood gene expression (microarray, quantitative polymerase chain reaction (qPCR)), plasma tumour necrosis factor (TNF)α (enzyme-linked immunosorbent assay (ELISA)), body composition (Dual-energy X-ray absorptiometry (DEXA)) and lipid profiles were assessed. Following consumption of juice concentrate, total cholesterol, low-density lipoprotein (LDL) cholesterol and plasma TNFα decreased and total lean mass increased, while there was no change in the placebo group. In subjects with high systemic inflammation at baseline (serum C-reactive protein (CRP) ≥3.0 mg/mL) who were supplemented with the F&V juice concentrate (n = 16), these effects were greater, with decreased total cholesterol, LDL cholesterol and plasma TNFα and increased total lean mass; plasma CRP was unchanged by the F&V juice concentrate following both analyses. The expression of several genes involved in lipogenesis, the nuclear factor-κB (NF-κB) and 5′ adenosine monophosphate-activated protein kinase (AMPK) signalling pathways was altered, including phosphomevalonate kinase (PMVK), zinc finger AN1-type containing 5 (ZFAND5) and calcium binding protein 39 (CAB39), respectively. Therefore, F&V juice concentrate improves the metabolic profile, by reducing systemic inflammation and blood lipid profiles and, thus, may be useful in reducing the risk of obesity-induced chronic disease

Floral resources encourage colonisation and use of green roofs by invertebrates

Acknowledgements: The authors would like to thank the numerous building managers, local residents, and the grounds team at Parliament house, who each assisted us with access to sites, and site-specific plant identification. We would also like to thank Dr. Georgia Garrard for her support in the development of this project, and two anonymous reviewers for their generous comments that greatly improved the final manuscript.Funder: Royal Melbourne Institute of TechnologyAbstractGreen roof retrofits offer a promising avenue to increase greenspace and thus biodiversity in the city. The successful colonisation and establishment of plants and animals on green roofs is limited by the location and context of the green roof. Here we use a before, after, control, impact (BACI) design to monitor the colonisation of a new retrofit roof in Melbourne CBD. We find that colonisation for some taxa occurs rapidly, with honeybees (Apis mellifera) arriving four days after flowers had been planted. Other insect taxa, such as native bees, did not colonise the impact roof but were present on the green roof reference site, which was lower in height and planted with native plants. Invertebrate abundance increased for all sites after the retrofit was built, however this sampling period was in late spring when more insects are expected to be active. Bird richness and abundance didn’t change in response to roof greening, but invertebrate richness was significantly higher on reference sites and increased after the green roof retrofit was built for the impact site. There was an apparent ‘spill over’ effect onto the nearby green roof control, which also increased in invertebrate diversity. Overall, invertebrate composition across roof types was driven by floral density. Floral density and richness increased on the impact roof as vegetation matured, subsequently correlating with higher abundance and richness of invertebrates. We use these findings to discuss colonisation of green roofs and argue for strategic placement of new green roof retrofits to maximise their biodiversity potential.</jats:p

Peak shift in honey bee olfactory learning

If animals are trained with two similar stimuli such that one is rewarding (S+) and one punishing (S-), then following training animals show a greatest preference not for the S+, but for a novel stimulus that is slightly more different from the S- than the S+ is. This peak shift phenomenon has been widely reported for vertebrates and has recently been demonstrated for bumblebees and honey bees. To explore the nature of peak shift in invertebrates further, here we examined the properties of peak shift in honey bees trained in a free-flight olfactory learning assay. Hexanal and heptanol were mixed in different ratios to create a continuum of odour stimuli. Bees were trained to artificial flowers such that one odour mixture was rewarded with 2 molar sucrose (S+), and one punished with distasteful quinine (S-). After training, bees were given a non-rewarded preference test with five different mixtures of hexanal and heptanol. Following training bees' maximal preference was for an odour mixture slightly more distinct from the S- than the trained S+. This effect was not seen if bees were initially trained with two distinct odours, replicating the classic features of peak shift reported for vertebrates. We propose a conceptual model of how peak shift might occur in honey bees. We argue that peak shift does not require any higher level of processing than the known olfactory learning circuitry of the bee brain and suggest that peak shift is a very general feature of discrimination learning.10 page(s

Austropuccinia psidii on the move: survey based insights to its geographical distribution, host species, impacts and management in Australia

Austropuccinia psidii is a plant fungus native to South and Central America which causes myrtle rust disease, affecting the growth and reproduction of species in the Myrtaceae family. Austropuccinia psidii was first detected in Australia 8 years ago in New South Wales. Since then it has spread rapidly along the east coast, and to date is known to infect more than 375 native Myrtaceae species in Australia. Despite this, its rapid spread is not well documented and the potential threat to additional Myrtaceae species remains unknown, with no systematic surveillance or monitoring program in Australia. In order to better understand the extent of A. psidii geographic distribution and impacts on Australian landscapes, a survey was sent to national park, botanical garden, local council, nursery and forestry agency employees in all states and territories where the disease is known to be present. More than 500 surveys were sent, and 254 responses were received. The survey confirms that A. psidii is widespread in New South Wales and Queensland urban environments as well as in native vegetation communities. Four new host species were confirmed, as well as four new local government areas in two different states reporting A. psidii infection. The disease severity was classified as medium to high for most host species, with especially negative impacts for Rhodamnia rubescens and Rhodomyrtus psidioides. These survey results provide up-to-date information on the geographical distribution, host species and impacts of A. psidii, which will assist in making management decisions relating to this pathogen across Australia

Austropuccinia psidii on the move: survey based insights to its geographical distribution, host species, impacts and management in Australia

Austropuccinia psidii is a plant fungus native to South and Central America which causes myrtle rust disease, affecting the growth and reproduction of species in the Myrtaceae family. Austropuccinia psidii was first detected in Australia 8 years ago in New South Wales. Since then it has spread rapidly along the east coast, and to date is known to infect more than 375 native Myrtaceae species in Australia. Despite this, its rapid spread is not well documented and the potential threat to additional Myrtaceae species remains unknown, with no systematic surveillance or monitoring program in Australia. In order to better understand the extent of A. psidii geographic distribution and impacts on Australian landscapes, a survey was sent to national park, botanical garden, local council, nursery and forestry agency employees in all states and territories where the disease is known to be present. More than 500 surveys were sent, and 254 responses were received. The survey confirms that A. psidii is widespread in New South Wales and Queensland urban environments as well as in native vegetation communities. Four new host species were confirmed, as well as four new local government areas in two different states reporting A. psidii infection. The disease severity was classified as medium to high for most host species, with especially negative impacts for Rhodamnia rubescens and Rhodomyrtus psidioides. These survey results provide up-to-date information on the geographical distribution, host species and impacts of A. psidii, which will assist in making management decisions relating to this pathogen across Australia

Soluble Fibre Meal Challenge Reduces Airway Inflammation and Expression of GPR43 and GPR41 in Asthma

Short chain fatty acids (SCFAs) are produced following the fermentation of soluble fibre by gut bacteria. In animal models, both dietary fibre and SCFAs have demonstrated anti-inflammatory effects via the activation of free fatty acid receptors, such as G protein-coupled receptor 41 and 43 (GPR41 and GPR43). This pilot study examined the acute effect of a single dose of soluble fibre on airway inflammation—including changes in gene expression of free fatty acid receptors—in asthma. Adults with stable asthma consumed a soluble fibre meal (n = 17) containing 3.5 g inulin and probiotics, or a control meal (n = 12) of simple carbohydrates. Exhaled nitric oxide (eNO) was measured and induced sputum was collected at 0 and 4 h for differential cell counts, measurement of interleukin-8 (IL-8) protein concentration, and GPR41 and GPR43 gene expression. At 4 h after meal consumption, airway inflammation biomarkers, including sputum total cell count, neutrophils, macrophages, lymphocytes, sputum IL-8, and eNO significantly decreased compared to baseline in the soluble fibre group only. This corresponded with upregulated GPR41 and GPR43 sputum gene expression and improved lung function in the soluble fibre group alone. Soluble fibre has acute anti-inflammatory effects in asthmatic airways. Long-term effects of soluble fibre as an anti-inflammatory therapy in asthma warrants further investigation

Effects of an Encapsulated Fruit and Vegetable Juice Concentrate on Obesity-Induced Systemic Inflammation: A Randomised Controlled Trial

Phytochemicals from fruit and vegetables reduce systemic inflammation. This study examined the effects of an encapsulated fruit and vegetable (F&amp;V) juice concentrate on systemic inflammation and other risk factors for chronic disease in overweight and obese adults. A double-blinded, parallel, randomized placebo-controlled trial was conducted in 56 adults aged ≥40 years with a body mass index (BMI) ≥28 kg/m2. Before and after eight weeks daily treatment with six capsules of F&amp;V juice concentrate or placebo, peripheral blood gene expression (microarray, quantitative polymerase chain reaction (qPCR)), plasma tumour necrosis factor (TNF)α (enzyme-linked immunosorbent assay (ELISA)), body composition (Dual-energy X-ray absorptiometry (DEXA)) and lipid profiles were assessed. Following consumption of juice concentrate, total cholesterol, low-density lipoprotein (LDL) cholesterol and plasma TNFα decreased and total lean mass increased, while there was no change in the placebo group. In subjects with high systemic inflammation at baseline (serum C-reactive protein (CRP) ≥3.0 mg/mL) who were supplemented with the F&amp;V juice concentrate (n = 16), these effects were greater, with decreased total cholesterol, LDL cholesterol and plasma TNFα and increased total lean mass; plasma CRP was unchanged by the F&amp;V juice concentrate following both analyses. The expression of several genes involved in lipogenesis, the nuclear factor-κB (NF-κB) and 5′ adenosine monophosphate-activated protein kinase (AMPK) signalling pathways was altered, including phosphomevalonate kinase (PMVK), zinc finger AN1-type containing 5 (ZFAND5) and calcium binding protein 39 (CAB39), respectively. Therefore, F&amp;V juice concentrate improves the metabolic profile, by reducing systemic inflammation and blood lipid profiles and, thus, may be useful in reducing the risk of obesity-induced chronic disease