Evolution and loss of long-fringed petals

Background: The Cucurbitaceae genus Trichosanthes comprises 90–100 species that occur from India to Japan and southeast to Australia and Fiji. Most species have large white or pale yellow petals with conspicuously fringed margins, the fringes sometimes several cm long. Pollination is usually by hawkmoths. Previous molecular data for a small number of species suggested that a monophyletic Trichosanthes might include the Asian genera Gymnopetalum (four species, lacking long petal fringes) and Hodgsonia (two species with petals fringed). Here we test these groups’ relationships using a species sampling of c. 60% and 4759 nucleotides of nuclear and plastid DNA. To infer the time and direction of the geographic expansion of the Trichosanthes clade we employ molecular clock dating and statistical biogeographic reconstruction, and we also address the gain or loss of petal fringes. Results: Trichosanthes is monophyletic as long as it includes Gymnopetalum, which itself is polyphyletic. The closest relative of Trichosanthes appears to be the sponge gourds, Luffa, while Hodgsonia is more distantly related. Of six morphology-based sections in Trichosanthes with more than one species, three are supported by the molecular results; two new sections appear warranted. Molecular dating and biogeographic analyses suggest an Oligocene origin of Trichosanthes in Eurasia or East Asia, followed by diversification and spread throughout the Malesian biogeographic region and into the Australian continent. Conclusions: Long-fringed corollas evolved independently in Hodgsonia and Trichosanthes, followed by two losses in the latter coincident with shifts to other pollinators but not with long-distance ispersal events. Together with the Caribbean Linnaeosicyos, the Madagascan Ampelosicyos and the tropical African Telfairia, these cucurbit lineages represent an ideal system for more detailed studies of the evolution and function of petal fringes in plant-pollinator mutualisms

High-Throughput Assay for the Identification of Compounds Regulating Osteogenic Differentiation of Human Mesenchymal Stromal Cells

Human mesenchymal stromal cells are regarded as the golden standard for cell-based therapies. They present multilineage differentiation potential and trophic and immunosuppressive abilities, making them the best candidate for clinical applications. Several molecules have been described to increase bone formation and were mainly discovered by candidate approaches towards known signaling pathways controlling osteogenesis. However, their bone forming potential is still limited, making the search for novel molecules a necessity. High-throughput screening (HTS) not only allows the screening of a large number of diverse chemical compounds, but also allows the discovery of unexpected signaling pathways and molecular mechanisms for a certain application, even without the prior knowledge of the full molecular pathway. Typically HTS is performed in cell lines, however, in this manuscript we have performed a phenotypical screen on more clinically relevant human mesenchymal stromal cells, as a proof of principle that HTS can be performed in those cells and can be used to find small molecules that impact stem cell fate. From a library of pharmacologically active small molecules, we were able to identify novel compounds with increased osteogenic activity. These compounds allowed achieving levels of bone-specific alkaline phosphatase higher than any other combination previously known. By combining biochemical techniques, we were able to demonstrate that a medium to high-throughput phenotypic assay can be performed in academic research laboratories allowing the discovery of novel molecules able to enhance stem cell differentiation

Traps as treats: a traditional sticky rice snack persisting in rapidly changing Asian kitchens

Background: An accessory to modern developing economies includes a shift from traditional, laborious lifestyles and cuisine to more sedentary careers, recreation and convenience-based foodstuffs. Similar changes in the developed western world have led to harmful health consequences. Minimization of this effect in current transitional cultures could be met by placing value on the maintenance of heritage-rich food. Vitally important to this is the preservation and dissemination of knowledge of these traditional foods. Here, we investigate the history and functionality of a traditional rice snack cooked in Nepenthes pitchers, one of the most iconic and recognizable plants in the rapidly growing economic environment of Southeast Asia. Methods: Social media was combined with traditional ethnobotanical surveys to conduct investigations throughout Malaysian Borneo. Interviews were conducted with 25 market customers, vendors and participants from various ethnical groups with an in-depth knowledge of glutinous rice cooked in pitcher plants. The acidity of pitcher fluid was measured during experimental cooking to analyze possible chemical avenues that might contribute to rice stickiness. Results: Participants identifying the snack were almost all (96%) from indigenous Bidayuh or Kadazandusun tribal decent. They prepare glutinous rice inside pitcher traps for tradition, vessel functionality and because they thought it added fragrance and taste to the rice. The pH and chemical activity of traps analyzed suggest there is no corresponding effect on rice consistency. Harvest of pitchers does not appear to decrease the number of plants in local populations. Conclusions: The tradition of cooking glutinous rice snacks in pitcher plants, or peruik kera in Malay, likely carries from a time when cooking vessels were more limited, and persists only faintly in tribal culture today because of value placed on maintaining cultural heritage. Social media proved a valuable tool in our research for locating research areas and in interviewing respondents, and we endorse its further use in ethnobotanical investigations. Our gathered data urges for the preservation of sustainable, tribal plant use for the prosperity of both health and cultur

The relationship between ecosystem services and human modification displays decoupling across global delta systems

The ties between a society and its local ecosystem can decouple as societies develop and replace ecosystem services such as food or water regulation via trade and technology. River deltas have developed into important, yet threatened, urban, agricultural and industrial centres. Here, we use global spatial datasets to explore how 49 ecosystem services respond to four human modification indicators, e.g. population density, across 235 large deltas. We formed bundles of statistically correlated ecosystem services and examined if their relationship with modification changed. Decoupling of all robust ecosystem service bundles from at least one modification indicator was indicated in 34% of deltas, while 53% displayed decoupling for at least one bundle. Food-related ecosystem services increased with modification, while the other bundles declined. Our findings suggest two developmental pathways for deltas: as coupled agricultural systems risking irreversible local biodiversity loss; and as decoupled urban centres externalising the impact of their growing demands

Biodiversity mediates relationships between anthropogenic drivers and ecosystem services across global mountain, island and delta systems

Global change increasingly threatens nature, endangering the ecosystem services human wellbeing depends upon. Biodiversity potentially mediates these impacts by providing resilience to ecosystems. While biodiversity has been linked to resilience and ecosystem service supply on smaller scales, we lack understanding of whether mediating interactions between biodiversity and anthropogenic drivers are global and ubiquitous, and how they might differ between systems. Here, we examine the potential for biodiversity to mediate anthropogenic driver-ecosystem service relationships using global datasets across three distinct systems: mountains, islands and deltas. We found that driver-ecosystem service relationships were stronger where biodiversity was more intact, and weaker at higher species richness, reflecting the negative correlation between intactness and richness. Mediation was most common in mountains, then islands, then deltas; reducing with anthropogenic impact. Such patterns were found across provisioning and regulating ecosystem services, and occurred most commonly with climate change and built infrastructure. Further, we investigated the contribution of biodiversity and abiotic and anthropogenic drivers to ecosystem services. Ecosystem service supply was associated with abiotic and anthropogenic drivers alongside biodiversity, but all drivers were important to different ecosystem services. Our results empirically show the importance of accounting for the different roles that biodiversity plays in mediating human relationships with nature, and reinforce the importance of maintaining intact biodiversity in ecosystem functioning

Consistent ecosystem service bundles emerge across global mountain, island and delta systems

Ecosystem services are often analysed individually, but are intertwined with one another and the social-ecological systems they occur in. As a response, ecosystem service bundles, i.e. co-occurring sets of ecosystem services, can be used to simplify complex relationships between nature and society, and in turn aid understanding. Typically bundles are studied on the local to regional scale, given the importance of local context to bundling, but wider scale analysis may help highlight broader ecosystem service balances for sustainable management. However, it remains uncertain if the relationships between ecosystem services are strong enough to describe coherent bundles at the global scale, and the extent to which these bundles are robust across different social-ecological systems and within different biogeographical realms. Here, we examine whether coherent bundles emerge from a set of 25 ecosystem property and service indicators across regional mountain, island and delta systems around the world. We analyse differences between bundle composition and correlation structure based on system, latitude and biome. We find consistent bundles broadly representing ‘food’, ‘productivity’ and biodiversity ‘intactness/soil’ ecosystem properties and services emerge across mountains, islands and deltas globally. These bundles show strong positive correlations internally, and consistent negative correlations between ‘food’ services and ‘intactness/soil’ ecosystem properties across bundles. The bundles weakened at higher latitudes and individual biomes where the division between ecosystem properties and services broke down. In sum, while islands, mountains and deltas are distinct social-ecological systems, we found ecosystem bundles robustly described synergies and trade-offs between ecosystem services across these systems. This suggests that bundling has a role in simplifying wider scale interactions between humans and ecosystem services

Environmental change and ecosystem functioning drive transitions in social-ecological systems: A stylized modelling approach

Sustainable management of social-ecological systems requires an understanding of how anthropogenic climate- and land use change may disrupt interactions between human societies and the ecosystem processes they depend on. In this study, we expand an existing stylized social-ecological system model by explicitly considering how urbanizing societies may become less dependent on local ecosystem functioning. This expansion is motivated by a previously developed conceptual framework suggesting that societies may reside in either a green loop and be strongly dependent on local ecosystem processes, or in a red loop where this dependency is weaker due to imports of natural resources from elsewhere. Analyzing the feasibility and stability of local social-ecological system states over a wide range of environmental and socio-economic conditions, we observed dynamics consistent with the notion of green loop-dominated and red loop-dominated societies comprising alternate stable social-ecological states. Based on systems' inherent dependencies on local ecosystem processes, responses to environmental change could comprise either transitions between green loop- and red loop-dominated states, or collapse of either of these states. Our quantitative model provides an internally consistent mapping of green loop- and red loop-dominated states, as well as transitions between or collapses of these states, along a gradient of environmental conditions

Development of chemical emission scenarios using the Shared Socio-economic Pathways

The widespread use of chemicals has led to significant water quality concerns, and their use is still increasing. Hence, there is an urgent need to understand the possible future trends in chemical emissions to water systems. This paper proposes a general framework for developing emission scenarios for chemicals to water using the Shared Socio-economic Pathways (SSPs) based on an emission-factor approach. The proposed approach involves three steps: (i) identification of the main drivers of emissions, (ii) quantification of emission factors based on analysis of publicly available data, and (iii) projection of emissions based on projected changes in the drivers and emission factors. The approach was tested in Europe for five chemical groups and on a national scale for five specific chemicals representing pharmaceuticals, pesticides, and industrial chemicals. The resulting emission scenarios show widely diverging trends of increased emissions by 240% for ibuprofen in SSP3 (regional rivalry) to a 68% decrease for diclofenac in SSP1 (sustainable development) by 2050. While emissions typically decrease in SSP1, they follow the historical trend in SSP2 (middle-of-the-road scenario) and show an increase in the regional rivalry scenario SSP3 for most selected chemicals. Overall, the framework allows understanding of future chemical emissions trends as a function of the socio-economic trends as captured in the SSPs. Our scenarios for chemical emissions can thus be used to model future aqueous emissions to support risk assessment. While the framework can be easily extended to other pharmaceuticals and pesticides, it heavily leans on the availability and quality of historical emission data and a detailed understanding of emission sources for industrial chemicals