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Although lowland tree species in the ever-wet regions of Southeast Asia are characterized by the supra-annual cycle of reproduction, the reproductive phenology of montane tree species remains poorly understood. In this study, we investigated the reproductive phenology of montane tree species using litter samples that were collected every 2 weeks from six rainforest sites, consisting of three elevations (1700, 2700, and 3100 m), on Mount Kinabalu, Borneo. At each elevation, one site was on infertile ultrabasic soil and one was on relatively fertile non-ultrabasic soil. We used a composite sample from 10 or 20 litter traps per site and sorted it by species. Therefore, the obtained data captured reproductive phenology in the population of each species rather than in an individual tree. Ten-year time series of flower and fruit litterfall were obtained for 30 and 39 tree species, respectively. Fourier analysis was used to identify the dominant cycle of each time series. The most abundant cycle across species was supra-annual, followed by sub-annual, and annual cycles. Many species at higher elevations showed supra-annual cycles of flower litterfall, whereas species in the 1700 m sites often showed annual or sub-annual cycles regardless of soil types. No systematic differences were found among sites for fruit litterfall. Mechanisms underlying these elevational patterns in reproductive cycle remain unclear but may include more severe El Niño droughts, lower primary productivity, lower soil fertility, and the absence of some sub-annually or annually reproducing families at higher elevations.

Volatile compounds in nectar have various functions, but we still know little about the distribution and functions of scented floral nectar. Here, we report functions of scented nectar in Fritillaria camtschatcensis. In Japan, F. camtschatcensis comprises two varieties, var. keisukei (hereafter, alpine type) and var. camtschatcensis (hereafter, lowland type), both of which secrete a large amount of scented nectar and attract flies as pollinators. We investigated sugar concentration of the nectar using high-performance liquid chromatography (HPLC) and studied the volatile chemical composition of the nectar using gas chromatography-mass spectrometry (GC-MS). We then conducted a bioassay using a synthetic mixture of components of the nectar scent of the lowland type to test if the nectar scent contributes to pollinator attraction. The HPLC analysis showed that substantial amounts of glucose and fructose occur in the nectar of the alpine type. The nectar of the lowland type also contained glucose, albeit at low concentration. The volatile compounds in the nectars were substantially different between the two types: the volatiles of the lowland type consisted of four aliphatic acids, whereas acetophenone was the main compound in the alpine type. The bioassay revealed that the nectar scent of the lowland type is sufficient to attract flies, including the pollinator species. This study showed that the nectar of F. camtschatcensis functions as both a reward and attractant for the pollinators, and indicates that flower nectar is much more diverse in terms of chemical composition and function than commonly thought.

Flowers are colonized and inhabited by diverse microbes. Flowers have various mechanisms to suppress microbial growth, such as flower volatiles, reactive oxygen and secondary compounds. Besides, plants rapidly replace flowers that have a short lifespan, and old flowers senesce. They may contribute to avoiding adverse effects of the microbes. In this study, we investigate if the flower microbial community on old flowers impedes fruit and seed production in a wild ginger with one-day flowers. We focus on microbes on old flowers because they may be composed of microbes that would grow during flowering if the flowers did not have mechanisms to suppress microbial growth. We inoculated newly opened flowers with old flower microbes, and monitored the effects on fruit and seed set. We also assessed prokaryotic communities on the flowers using 16S rRNA amplicon sequencing. We found six bacterial amplicon sequence variants (ASVs) whose proportions were increased on the inoculated flowers. These ASVs were also found on flower buds and flowers that were bagged by net or paper during anthesis, suggesting that they had been present in small numbers prior to flowering. Fruit set was negatively associated with the proportions of these ASVs, while seed set was not. The results suggest that old flowers harbor microbial communities different from those at anthesis, and that the microbes abundant on old flowers negatively affect plant reproduction. Although it has received little attention, antagonistic microbes that rapidly proliferate on the flowers may have affected the evolution of various flower characteristics such as flower volatiles and life span.

Root water uptake depth and its temporal variation are important determinants of tree mortality, resource partitioning and drought resistance; however, their effects on tropical trees remain poorly understood. In this study, we investigated interspecific differences in water uptake depth and its temporal variation using stable isotope analysis and examined the relationships between water uptake depth and aboveground traits in a humid aseasonal tropical rainforest in Borneo. Species-specific differences in water uptake depth were examined for six dominant dipterocarp species. Temporal variation in water uptake depth for various canopy trees was assessed in three periods with different soil moisture conditions. We then examined the relationships between water uptake depth and aboveground traits including wood density, maximum tree height, flowering frequency and growth rate. Dipterocarpus globosus appeared to be more reliant on deep water resources than the other dipterocarp species. Water uptake from the soil layers varied among the three sampling periods. Trees generally utilized deeper soil water during the second driest sampling period, when temperatures were lowest. During the driest and wettest sampling periods, species with higher flowering frequencies tended to preferentially uptake deep soil water. These results suggest that low temperature and soil moisture promote increased deep soil water uptake in the study region. Dynamic relationships between water uptake patterns and aboveground tree traits may be related to resource partitioning among co-existing species.

We present an analysis of the long-term performance of the W. M. Keck observatory laser guide star adaptive optics (LGS-AO) system and explore factors that influence the overall AO performance most strongly. Astronomical surveys can take years or decades to finish, so it is worthwhile to characterize the AO performance on such timescales in order to better understand future results. The Keck telescopes have two of the longest-running LGS-AO systems in use today, and as such they represent an excellent test-bed for processing large amounts of AO data. We use a Keck-II near infrared camera 2 (NIRC2) LGSAO surve of the Galactic Center (GC) from 2005 to 2019 for our analysis, combining image metrics with AO telemetry files, multiaperture scintillation sense/differential imaging motion monitor turbulence profiles, seeing information, weather data, and temperature readings in a compiled dataset to highlight areas of potential performance improvement. We find that image quality trends downward over time, despite multiple improvements made to Keck-II and its AO system, resulting in a 9 mas increase in the average full width at half maximum (FWHM) and a 3% decrease in the average Strehl ratio over the course of the survey. Image quality also trends upward with ambient temperature, possibly indicating the presence of uncorrected turbulence in the beam path. Using nine basic features from our dataset, we train a simple machine learning (ML) algorithm to predict the delivered image quality of NIRC2 given current atmospheric conditions, which could eventually be used for real-time observation planning and exposure time adjustments. A random forest algorithm trained on this data can predict the Strehl ratio of an image to within 18% and the FWHM to within 7%, which is a solid baseline for future applications involving more advanced ML techniques. The assembled dataset and coding tools are released to the public as a resource for testing new predictive control and point spread function-reconstruction algorithms.

Mutualistic interactions between species are ubiquitous in nature and essential for ecosystem functioning. Often dozens or even hundreds of species with different degrees of specialisation form complex networks. How this complexity evolves is a fundamental question in ecology. Here, we present a new game theoretical approach to model complex coevolutionary processes and apply it to pollination networks. A theoretical analysis reveals multiple evolutionary stable network structures that depend on the availability of pollination service. In particular, we find efficient communities, in which a high percentage of pollen are transported conspecifically, to evolve only when plant and pollinator abundances are well balanced. Both pollinator shortage and oversupply select for more inefficient network structures. The results suggest that availability of pollination services is a key factor structuring pollination networks and may offer a new explanation for geographical differences in pollination communities that have long been recognised by ecologists.

Specific conditions, such as exposure to cold, can induce the production of brown-like adipocytes in white adipose tissue. These adipocytes express high levels of uncoupling protein 1 (UCP1) and energy expended by generating heat. Thus, these are a potential target for the prevention or treatment of obesity. The present study involved a comprehensive analysis of the adipose tissue to understand the relationship between long non-coding RNA (lncRNA) 2310069B03Rik and UCP1. Cold exposure increased both lncRNA 2310069B03Rik and Ucp1 expression in inguinal white adipose tissue (iWAT). However, overexpression of lncRNA 2310069B03Rik suppressed the Ucp1 mRNA expression and the promoter activity of UCP1 in the iWAT primary adipocytes. In addition, compared to the early induction of Ucp1 expression by cold stimulation, the induction of lncRNA 2310069B03Rik expression was later. These results suggest that lncRNA 2310069B03Rik functions as a suppression factor of Ucp1 expression.

Supra-annually synchronized flowering events occurring in tropical forests in Southeast Asia, known as general flowering (GF), are “spectacular and mysterious” forest events. Recently, studies that combined novel molecular techniques and model-based theoretical approaches suggested that cool temperature and drought synergistically drove GF. Although the novel approaches advanced our understanding of GF, it is usually difficult to know whether the mathematical formulation reasonably well represents the complex and dynamic processes involved in GF. In the present study, we collected a 17-year set of community-wide phenology data during 1993 to 2011 from Lambir Hills National Park in Borneo, Malaysia, and analyzed it using a model-free approach, empirical dynamic modeling (EDM), that does not rely on specific assumptions about the underlying mechanisms, to overcome and complement the previous limitations. By using EDM, we found that GF in the forest in Lambir Hills National Park is synergistically driven by cool air temperature and drought, which is consistent with the previous studies. Also, we found that cumulative meteorological variables, rather than instantaneous values, drive GF with delayed effects, which is also consistent with the previous studies. Interestingly, the present study showed that effects of cumulative meteorological variables on GF changed through time, which implies that the relationship between GF and meteorological variables may be influenced by other factors such as plant/soil nutrient resource dynamics. Future studies integrating novel mathematical/statistical frameworks, long-term and large spatial scale ecosystem monitoring and molecular phenology data are promising for better understanding and fore-casting of GF events in tropical forests in Southeast Asia.

Individual plants can produce leaves that differ substantially in size, morphology and many other traits. However, leaves that play a specific role in reproduction have rarely been reported. Here, we report leaves specialized to enclose fruit clusters and enhance seed production in an annual vine, Schizopepon bryoniifolius. Enclosure leaves were produced at the end of the growing season in late autumn. They were different in greenness and structure from other leaves. Under solar radiation, the ambient temperature inside an intact enclosure was up to 4.6°C higher than that near a fruit cluster whose enclosure leaves had been removed. We found that enclosures were thicker at colder sites. Removal of enclosing leaves negatively affected fruit survival and/or growth, but we could not identify the exact mechanism. The results suggested that enclosures allow the plant to produce seeds under the cold weather the plant encounters at the end of its life. Vegetative and reproductive traits of plants have usually been studied separately. This study indicates how they can dynamically interact, as shown by an examination of associations among leaf and reproductive trait changes according to life stages.

Certain copy number alterations (CNAs) are strongly associated with particular cancer types. However, the mechanisms that underlie selection of specific CNAs remain unknown. Here, we identified functional relationships between recurrent CNAs in colorectal cancers (CRCs) and adenomatous polyposis coli (APC) mutations. Quantitative phenotyping of mitotic spindles highlighted APC functions at centrosomes where APC positively regulated Aurora A kinase (AURKA). Upon APC inactivation, elevated β-catenin levels blocked AURKA activation, which caused chromosome instability and suppressed proliferation, resulting in the generation and selection of AURKA-activating CNAs. Arm-level amplification of chromosomes that contained AURKA and AURKA activator genes was observed in APC-mutant CRCs, early stage mouse tumours, and cells in culture, which was concomitant with an increase in growth potential. Our findings demonstrate a mechanism that restores tumour cell fitness through compensatory chromosome alterations to overcome adverse effects of prior mutations, which may affect the course of cancer type-specific CNA formation.

Searching for space-time variations of the constants of Nature is a promising way to search for new physics beyond General Relativity and the standard model motivated by unification theories and models of dark matter and dark energy. We propose a new way to search for a variation of the fine-structure constant using measurements of late-type evolved giant stars from the S-star cluster orbiting the supermassive black hole in our Galactic Center. A measurement of the difference between distinct absorption lines (with different sensitivity to the fine structure constant) from a star leads to a direct estimate of a variation of the fine structure constant between the star's location and Earth. Using spectroscopic measurements of 5 stars, we obtain a constraint on the relative variation of the fine structure constant below $10^{-5}$. This is the first time a varying constant of Nature is searched for around a black hole and in a high gravitational potential. This analysis shows new ways the monitoring of stars in the Galactic Center can be used to probe fundamental physics., Comment: 7 pages + 10 pages appendix, 3 figures, version accepted for publication

Premise of the Study: In animal‐dispersed plants, seed dispersal patterns of the same species in the same habitat can greatly differ among individuals and temporally. Many studies have revealed the pervasive effects of spatial variation in fruit abundance on seed dispersal of individual plants. By contrast, very few studies have investigated the temporal variation in seed dispersal. Methods: We investigated the effects of conspecific and community‐level fruit abundance on fruit removal rate and seed dispersal distance of six bird‐dispersed woody species in a Japanese temperate forest for 3 yr. The six species share similar fruit characteristics but have different fruiting seasons. In addition, we also considered the effects of bird seasonality in diet and species composition on seed dispersal. Key Results: Inter‐annual and inter‐seasonal variation in community‐level fruit abundance determined both fruit removal and the seed dispersal distance across species, but the effect differed with seasonal changes in bird behavior. Abundant fruit satiated fruit removal by birds only during fruit‐feeding periods, not during insect‐feeding periods. A scarcity of fruit increased the dispersal distance, but only during the migratory period. This difference was probably due to the different foraging behaviors of passing migrants and territorial birds. Conclusions: Our results illustrated that temporal variation in community‐level fruit abundance could be a determining factor for seed dispersal in temperate forests. The effects of temporal variations in fruit abundance on seed dispersal patterns should be investigated in other ecosystems in order to understand their importance and associations with frugivore phenology., 動物による種子散布メカニズムの一端を解明 --森の果実の豊凶が鳥のタネまきを左右する--. 京都大学プレスリリース. 2018-10-15.

Better understanding tax systems is key to reducing disparity and inequality, and therefore has the potential to ultimately improve societies. The research of Associate Professor Dr Shoko Sakai, Kaetsu University, Japan, is investigating the optimum tax system for financial stability through empirical analyses and is also using quantitative data to explore taxation issues. Specifically, the research is using quantitative data to consider tax reforms and changes in social conditions of countries outside of Japan over the past few years, especially those with strong welfare systems. It will also explore the fair tax burden according to the taxpaying ability and appropriate distribution to the necessary households. These investigations are expected to assist in the development of tax policy recommendations. The goal of the work is to pave the way towards stable economic foundations and a sustainable social security system and, ultimately, assist in the future development of Japan's economy and improve its society. This goal is being realised through collaboration with other researchers; Ulf Olovsson, Deputy Secretary, Tax and Customs Bureau, Ministry of Finance, as well as receiving support from Associate Professor Eiji Sawada of Kyushu Sangyo University regarding numerical simulation, data construction and analysis. This collaborative effort will facilitate the development of recommendations that will lead to national policies and an improved society, in which inequalities are reduced.

Supply of non-timber Forest Products (NTFPs) is an important provisioning ecosystem service. It is often argued that forest conservation contributes to poverty alleviation through provisioning of NTFPs to the poor. However, implicit assumptions of the argument that NTFPs are more intensively utilized by poor who lack alternative subsistence options, and that NTFP supplies are limited by forest cover, have rarely been critically examined. This study investigated social and environmental factors affecting NTFP uses in rural areas of Borneo, using a land cover map and socio-economic dataset collected from 1596 households in 87 villages. The NTFPs examined were wild boars, sambar deer, wild fruits, firewood, wild vegetables, and wild mushrooms. To explain the variations in NTFP uses among households, four village and nine household characteristics were considered using generalized linear mixed models. We found that forest cover and collection pressure limit the use of some NTFPs, supporting the second assumption. On the other hand, the first assumption was supported only for firewood, and animals and wild fruits were more frequently used by wealthier households, contrary to this assumption. Other factors (education, age and sex of householder and agricultural activities) were also related to the use of one or more NTFPs. This study demonstrates the complexity of the process by which forest cover and other factors affect the ecosystem services people receive. Evaluation of ecosystem services is an important and urgent research subject today, but it is also necessary to pay attention to who receives the benefits, and who does not.

The electromagnetic counterpart to the Galactic center supermassive black hole, Sgr A∗, has been observed in the near-infrared for over 20 yr and is known to be highly variable. We report new Keck Telescope observations showing that Sgr A∗ reached much brighter flux levels in 2019 than ever measured at near-infrared wavelengths. In the K′ band, Sgr A∗ reached flux levels of ∼6 mJy, twice the level of the previously observed peak flux from >13,000 measurements over 130 nights with the Very Large Telescope and Keck Telescopes. We also observe a factor of 75 change in flux over a 2 hr time span with no obvious color changes between 1.6 and 2.1 μm. The distribution of flux variations observed this year is also significantly different than the historical distribution. Using the most comprehensive statistical model published, the probability of a single night exhibiting peak flux levels observed this year, given historical Keck observations, is less than 0.3%. The probability of observing flux levels that are similar to all four nights of data in 2019 is less than 0.05%. This increase in brightness and variability may indicate a period of heightened activity from Sgr A∗ or a change in its accretion state. It may also indicate that the current model is not sufficient to model Sgr A∗ at high flux levels and should be updated. Potential physical origins of Sgr A∗'s unprecedented brightness may be from changes in the accretion flow as a result of the star S0-2's closest passage to the black hole in 2018, or from a delayed reaction to the approach of the dusty object G2 in 2014. Additional multi-wavelength observations will be necessary to both monitor Sgr A∗ for potential state changes and to constrain the physical processes responsible for its current variability.© 2019. The American Astronomical Society. All rights reserved.., We thank the anonymous referee for helpful comments. We thank the staff and astronomers at Keck Observatory especially Jim Lyke, Randy Campbell, Sherry Yeh, Greg Doppmann, Cynthia Wilburn, Terry Stickel, and Alan Hatakeyama. Support for this work was provided by NSF AAG grant AST-1412615, the W.M. Keck Foundation, the HeisingSimons Foundation, the Gordon and Betty Moore Foundation, the Levine-Leichtman Family Foundation, the Preston Family Graduate Fellowship (held by A.G.), and the UCLA Galactic Center Star Society. R. S. has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement No. 614922. R.S. acknowledges financial support from the State Agency for Research of the Spanish MCIU through the >Center of Excellence Severo Ochoa> award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709). This research was based on data products from the Galactic Center Orbits Initiative, which is hosted at UCLA and is a key science program of the Galactic Center Collaboration. The W.M. Keck Observatory is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. The authors wish to recognize that the summit of Maunakea has always held a very significant cultural role for the indigenous Hawaiian community. We are most fortunate to have the opportunity to observe from this mountain.

Supra-annually synchronized flowering events occurring in tropical forests in Southeast Asia, known as general flowering (GF), are “spectacular and mysterious” forest events. Recently, studies that combined novel molecular techniques and model-based theoretical approaches suggested that cool temperature and drought synergistically drove GF. Although the novel approaches advanced our understanding of GF, it is usually difficult to know whether the mathematical formulation reasonably well represents the complex and dynamic processes involved in GF. In the present study, we collected a 17-year set of community-wide phenology data during 1993 to 2011 from Lambir Hills National Park in Borneo, Malaysia, and analyzed it using a model-free approach, empirical dynamic modeling (EDM), that does not rely on specific assumptions about the underlying mechanisms, to overcome and complement the previous limitations. By using EDM, we found that GF in the forest in Lambir Hills National Park is synergistically driven by cool air temperature and drought, which is consistent with the previous studies. Also, we found that cumulative meteorological variables, rather than instantaneous values, drive GF with delayed effects, which is also consistent with the previous studies. Interestingly, the present study showed that effects of cumulative meteorological variables on GF changed through time, which implies that the relationship between GF and meteorological variables may be influenced by other factors such as plant/soil nutrient resource dynamics. Future studies integrating novel mathematical/statistical frameworks, long-term and large spatial scale ecosystem monitoring and molecular phenology data are promising for better understanding and fore-casting of GF events in tropical forests in Southeast Asia.

We present improved relative astrometry for stars within the central half parsec of our Galactic Center (GC) based on data obtained with the 10 m W. M. Keck Observatory from 1995 to 2017. The new methods used to improve the astrometric precision and accuracy include correcting for local astrometric distortions, applying a magnitude-dependent additive error, and more carefully removing instances of stellar confusion. Additionally, we adopt jackknife methods to calculate velocity and acceleration uncertainties. The resulting median proper motion uncertainty is 0.05 mas yr -1 for our complete sample of 1184 stars in the central 10″ (0.4 pc). We have detected 24 accelerating sources, 2.6 times more than the number of previously published accelerating sources, which extend out to 4″ (0.16 pc) from the black hole. Based on S0-2's orbit, our new astrometric analysis has reduced the systematic error of the supermassive black hole (SMBH) by a factor of 2. The linear drift in our astrometric reference frame is also reduced in the north-south direction by a factor of 4. We also find the first potential astrometric binary candidate S0-27 in the GC. These astrometric improvements provide a foundation for future studies of the origin and dynamics of the young stars around the SMBH, the structure and dynamics of the old nuclear star cluster, the SMBH's properties derived from orbits, and tests of general relativity in a strong gravitational field. © 2019. The American Astronomical Society. All rights reserved., We acknowledge support from the W. M. Keck Foundation, the Heising Simons Foundation, and the National Science Foundation (AST-1412615, AST1518273). The research leading to these results has received funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement No. [614922]. The W. M. Keck Observatory is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

Precision measurements of the stars in short-period orbits around the supermassive black hole at the Galactic Center are now being used to constrain general relativistic effects, such as the gravitational redshift and periapse precession. One of the largest systematic uncertainties in the measured orbits has been errors in the astrometric reference frame, which is derived from seven infrared-bright stars associated with SiO masers that have extremely accurate radio positions, measured in the Sgr A*-rest frame. We have improved the astrometric reference frame within 14'' of the Galactic Center by a factor of 2.5 in position and a factor of 5 in proper motion. In the new reference frame, Sgr A* is localized to within a position of 0.645 mas and proper motion of 0.03 mas/yr. We have removed a substantial rotation (2.25 degrees per decade), that was present in the previous less-accurate reference frame used to measure stellar orbits in the field. With our improved methods and continued monitoring of the masers, we predict that orbital precession predicted by General Relativity will become detectable in the next ~5 years., 17 pages, 10 figures

Made available in DSpace on 2019-10-06T16:57:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-23 British Ecological Society Consejo Nacional de Investigaciones Científicas y Técnicas Background and Aims: Large clades of angiosperms are often characterized by diverse interactions with pollinators, but how these pollination systems are structured phylogenetically and biogeographically is still uncertain for most families. Apocynaceae is a clade of >5300 species with a worldwide distribution. A database representing >10 % of species in the family was used to explore the diversity of pollinators and evolutionary shifts in pollination systems across major clades and regions. Methods: The database was compiled from published and unpublished reports. Plants were categorized into broad pollination systems and then subdivided to include bimodal systems. These were mapped against the five major divisions of the family, and against the smaller clades. Finally, pollination systems were mapped onto a phylogenetic reconstruction that included those species for which sequence data are available, and transition rates between pollination systems were calculated. Key Results: Most Apocynaceae are insect pollinated with few records of bird pollination. Almost three-quarters of species are pollinated by a single higher taxon (e.g. flies or moths); 7 % have bimodal pollination systems, whilst the remaining approx. 20 % are insect generalists. The less phenotypically specialized flowers of the Rauvolfioids are pollinated by a more restricted set of pollinators than are more complex flowers within the Apocynoids + Periplocoideae + Secamonoideae + Asclepiadoideae (APSA) clade. Certain combinations of bimodal pollination systems are more common than others. Some pollination systems are missing from particular regions, whilst others are over-represented. Conclusions: Within Apocynaceae, interactions with pollinators are highly structured both phylogenetically and biogeographically. Variation in transition rates between pollination systems suggest constraints on their evolution, whereas regional differences point to environmental effects such as filtering of certain pollinators from habitats. This is the most extensive analysis of its type so far attempted and gives important insights into the diversity and evolution of pollination systems in large clades. Faculty of Arts Science and Technology University of Northampton, Newton Building, Avenue Campus Lehrstuhl für Pflanzensystematik Universität Bayreuth Department of Systematic and Evolutionary Botany University of Zurich, Zollikerstrasse 107 Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) Curso de Licenciatura em Educação do Campo - LEC Campus JK - Diamantina School of Life Sciences University of KwaZulu-Natal, Private Bag X01 Instituto de Botánica del Nordeste UNNE-CONICET Department of Plant Biology Ecology and Evolution, 301 Physical Sciences Laboratorio de Plantas Vasculares Departamento de Biología Comparada Facultad de Ciencias UNAM Laboratório de Ecologia da Polinização e Interações - LEPI Departamento de Botânica Instituto de Biociências Universidade Estadual Paulista 'Júlio de Mesquita Filho'- Unesp Saint Louis University Department of Biology Biology Extension Building, 1008 S. Spring Ave. Mehmet Akif Ersoy Mah. 269. Cad. Urankent Prestij Konutlarý Department of Biological Sciences University of Cape Town, P/Bag X3 Ecosystem Management Group ETH Zurich EDB UMR 5174 Université de Toulouse UPS, 118 route de Narbonne Laboratorio de Ecología Evolutiva - Biología Floral IMBIV (UNC-CONICET) Departamento de Botânica Museu Nacional Universidade Federal do Rio de Janeiro Quinta da Boa Vista Department of Plant Sciences Faculty of Natural and Agricultural Sciences University of the Free State, PO Box 339 Laboratório de Ciências Ambientais Centro de Biociências e Biotecnologia Universidade Estadual do Norte Fluminense Darcy Ribeiro Departamento de Botânica - CB Laboratório de Biologia Floral e Reprodutiva - POLINIZAR Universidade Federal de Pernambuco Universidade Federal de São Carlos - UFSCar Centro de Ciências Agrárias Depto. Ciências da Natureza Matemática e Educação, Rod. Anhanguera Km 174 Jardim Botânico do Rio de Janeiro, Rua Pacheco Leão 915 Facultad de Ciencias Exactas Fisicas y Naturales Universidad Nacional de Córdoba (UNC) IMBIV (CONICET-UNC) Herbarium - Royal Botanic Gardens Laboratorio de Investigaciones Botánicas (LABIBO) Facultad de Ciencias Naturales Universidad Nacional de Salta-CONICET, Av. Bolivia 5150 Department of Biosciences University of Salzburg Biology Department Franklin and Marshall College Natural History Museum Georgia College, 231 W. Hancock Street Centre for Ecology and Conservation University of Exeter Penryn Campus Department of Biology Willamette University Department of Botany Faculty of Science Chulalongkorn University, Phayathai Road Department of Biodiversity Earth and Environmental Sciences Academy of Natural Sciences Drexel University Center for Ecological Research Kyoto University, Hirano 2-509-3 Universidade Estadual Paulista UNESP Instituto de Biociências Departamento de Botânica Laboratório de Fenologia Tanzania Wildlife Research Institute (TAWIRI), PO Box 661 School of Biological Sciences Royal Holloway University of London Graduate School of Arts and Sciences University of Tokyo, 3-8-1 Komaba Universidade do Estado da Bahia, Campus IX. Rodovia BR 242, km 4, s/n. Flamengo Tropical Biology Association David Attenborough Building, Pembroke Street Instituto de Biologia - UFU, Campus Umuarama Bloco 2D Department of Botany Rhodes University, PO Box 94 Biospheres Eshwari, 52/403, Nanasaheb Peshva Marg, Near Ramna Ganpati Department of Evolution Ecology and Organismal Biology University of California Riverside, 900 University Avenue Departamento de Biologia Universidade Estadual de Feira de Santana, Av. Universitária s/n, Novo Horizonte Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany Chinese Academy of Sciences, 132 Lanhei Road Laboratorio de Ecología UBIPRO FES-Iztacala Universidad Nacional Autónoma de México Tlalnepantla de Baz Escuela de Ciencias Biológicas Universidad Pedagógica y Tecnológica de Colombia Departamento de Biologia Vegetal Instituto de Biologia Universidade Estadual de Campinas, Caixa Postal 6109 Department of Plant Sciences Natural and Agricultural Sciences University of the Free State, Qwaqwa campus, Kestell Road Penn State University, 542 ASI Building Department of Chemistry and Bioscience Aalborg University, Fredrik Bajers Vej 7H Graduate School of Human Development and Environment Kobe University, 3-11 Tsurukabuto Departamento de Biologia Vegetal Universidade Federal de VIçosa (UFV) Museo Botánico Córdoba y Cátedra de Morfologia Vegetal (IMBIVUNC-CONICET) Graduate School of Technology Industrial and Social Science Tokushima University, 2-1 Minamijyosanjima Centro Acadêmico de Vitória Universidade Federal de Pernambuco Departamento de Educação Universidade Federal da Paraiba Departamento de Engenharia e Meio Ambiente Universidade Federal da Paraiba Laboratório de Ecologia da Polinização e Interações - LEPI Departamento de Botânica Instituto de Biociências Universidade Estadual Paulista 'Júlio de Mesquita Filho'- Unesp Universidade Estadual Paulista UNESP Instituto de Biociências Departamento de Botânica Laboratório de Fenologia

The general theory of relativity predicts that a star passing close to a supermassive black hole should exhibit a relativistic redshift. In this study, we used observations of the Galactic Center star S0-2 to test this prediction.We combined existing spectroscopic and astrometric measurements from 1995-2017, which cover S0-2's 16-year orbit, with measurements from March to September 2018, which cover three events during S0-2's closest approach to the black hole. We detected a combination of special relativistic and gravitational redshift, quantified using the redshift parameter ϒ. Our result, ϒ = 0.88 ± 0.17, is consistent with general relativity (ϒ = 1) and excludes a Newtonian model (U = 0) with a statistical significance of 5ω.Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science, This research was supported by the National Key Research and Development Program of China (2016YFD0100404), the National Natural Science Foundation of China (91535108), the Recruitment Program of Global Experts, and the Fundamental Research Funds for the Central Universities.

We propose a new approach to Bayesian prior probability distributions (priors) that can improve orbital solutions for low-phase-coverage orbits, where data cover less than approximately 40% of an orbit. In instances of low phase coverage such as with stellar orbits in the Galactic center or with directly-imaged exoplanets, data have low constraining power and thus priors can bias parameter estimates and produce under-estimated confidence intervals. Uniform priors, which are commonly assumed in orbit fitting, are notorious for this. We propose a new observable-based prior paradigm that is based on uniformity in observables. We compare performance of this observable-based prior and of commonly assumed uniform priors using Galactic center and directly-imaged exoplanet (HR 8799) data. The observable-based prior can reduce biases in model parameters by a factor of two and helps avoid under-estimation of confidence intervals for simulations with less than about 40% phase coverage. Above this threshold, orbital solutions for objects with sufficient phase coverage such as S0-2, a short-period star at the Galactic center with full phase coverage, are consistent with previously published results. Below this threshold, the observable-based prior limits prior influence in regions of prior dominance and increases data influence. Using the observable-based prior, HR 8799 orbital analyses favor lower eccentricity orbits and provide stronger evidence that the four planets have a consistent inclination around 30 degrees to within 1-sigma. This analysis also allows for the possibility of coplanarity. We present metrics to quantify improvements in orbital estimates with different priors so that observable-based prior frameworks can be tested and implemented for other low-phase-coverage orbits., Comment: Published in AJ. 23 pages, 14 figures. Monte Carlo chains are available in the published article, or are available upon request

Many plants have mutualistic relationships with ants, whereby plants provide food and/or nesting sites for the symbiotic ants, and in turn the ants protect the host plants by excluding herbivores. While the ants are useful as guards, they may negatively affect host reproduction by excluding pollinators. Here we studied this potential conflict in the myrmecophytic Macaranga winkleri pollinated by the thrips Dolichothrips fialae. Behavioural responses of ant guards to pollinator thrips and their chemicals, and related chemical analyses, provide evidence that thrips deter ant-guards by secreting droplets containing ant-repelling n-decanoic acid from their anuses. This is the first report of insect pollinators repelling their host’s symbiotic guard ants to perform pollination. This is a novel strategy by which a plant host avoids interference with pollination by ant-guards in an ant–plant mutualism. The acquisition of a pollination system that is resistant to ant attacks may have facilitated the evolution of myrmecophytes in the genus Macaranga.

We present a $\approx 11.5$ year adaptive optics (AO) study of stellar variability and search for eclipsing binaries in the central $\sim 0.4$ pc ($\sim 10''$) of the Milky Way nuclear star cluster. We measure the photometry of 563 stars using the Keck II NIRC2 imager ($K'$-band, $\lambda_0 = 2.124 \text{ } \mu \text{m}$). We achieve a photometric uncertainty floor of $\Delta m_{K'} \sim 0.03$ ($\approx 3\%$), comparable to the highest precision achieved in other AO studies. Approximately half of our sample ($50 \pm 2 \%$) shows variability. $52 \pm 5\%$ of known early-type young stars and $43 \pm 4 \%$ of known late-type giants are variable. These variability fractions are higher than those of other young, massive star populations or late-type giants in globular clusters, and can be largely explained by two factors. First, our experiment time baseline is sensitive to long-term intrinsic stellar variability. Second, the proper motion of stars behind spatial inhomogeneities in the foreground extinction screen can lead to variability. We recover the two known Galactic center eclipsing binary systems: IRS 16SW and S4-258 (E60). We constrain the Galactic center eclipsing binary fraction of known early-type stars to be at least $2.4 \pm 1.7\%$. We find no evidence of an eclipsing binary among the young S-stars nor among the young stellar disk members. These results are consistent with the local OB eclipsing binary fraction. We identify a new periodic variable, S2-36, with a 39.43 day period. Further observations are necessary to determine the nature of this source., Comment: 69 pages, 28 figures, 12 tables. Accepted for publication in The Astrophysical Journal

Mutualistic interactions between species such as pollination and plant–mycorrhiza interactions are ubiquitous in nature and essential for ecosystem functioning. Often dozens or even hundreds of species with different degree of specialization form complex networks of interdependence. How the complexity evolved and is maintained are fundamental questions in ecology. Here, we present a new game theoretical approach to model complex mutualistic interactions, which we apply to pollination networks. The theoretical analysis revealed multiple evolutionary stable network structures that form a gradient from generalism toward specialism with increasing availability of pollination service. In particular, we found that efficient communities evolve only under pollination oversupply, but that pollination shortage selects for inefficient network structures due to a pollination dilemma. These results suggest that availability of pollination services is a key factor structuring pollination networks and offer a new explanation for the geographical differences in pollination faunas that have long been recognized by ecologists. The study bridges the gap between network studies, game theory, and the natural history of pollination, which have hitherto been studied largely independently.

International audience; With global science-policy conventions for biodiversity and ecosystem services in place, much effort goes into monitoring and reporting on the progress toward policy targets. As conservation actions happen locally, can such global monitoring and reporting efforts effectively guide conservation. actions at subnational level? In this paper we explore three different perspectives: policy reporting for policy implementation; scientific knowledge for empowerment and actions; and from past trends to influencing the future. Using these three perspectives, we identify ways forward for both decision makers and scientists on how to engage, inform and empower a larger diversity of actors who make decisions on the future of biodiversity and ecosystem services at multiple scales Without doubt, scientific understanding of why and where biodiversity and ecological resilience are degrading is advancing [1",2]. In addition, there is enormous investment and engagement by both decision makers and scientists to maintain and raise the environmental stakes on international policy agendas in the face of worldwide economic, social and political challenges. Global biodiversity targets as set by the signatories to the Convention on Biological Diversity in 2010 (the Aichi targets), the 2013 European Union strategy on adaptation to climate change, and the Sustainable Development Goals, require short to medium term action in translating such targets to local conservation actions [e.g. 3], for instance at the level of protected areas, watersheds or a village [4]. With the first thematic, regional and global assessment reports of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) being published [5,6] or steadily advancing, it is timely to reflect on how the substantial scientific and political investments in monitoring and reporting on progress toward global biodiversity and ecosystem service targets can be used effectively for conservation actions. Taking the perspective of societal actors faced with subnational or site based conservation challenges, we explore the possible guidance that these global initiatives may provide. As the ultimate objective is to decrease biodiversity degradation [7], frequent back casting of the extent of biodiversity and ecosystem services loss for reporting does not necessarily provide guidance on what to do differently to curb downward trends in the future [8'']. A different approach is therefore required to obtain and use information from global conventions to enhance the effectiveness of so cietal actors in addressing local biodiversity degradation. A lack of information is only one of many factors mentioned when listing impediments to the impact of local conservation actions. Empowerment of local actors, multi-actor mobilization and addressing the impaired effectiveness of governance are measures that have been suggested as steps toward curbing current biodiversity trends [9,10'',11–13], steps which cannot be taken by decision makers, scientists or NGOs in isolation or bilaterally. In this paper we reflect on: policy reporting for policy implementation; scientific knowledge for empowerment and actions; and from past trends to influencing the future. From these three perspectives, we identify ways forward for both decision makers and scientists on how to engage with, inform and empower a larger diversity of actors that take decisions on the future of biodiversity and ecosystem services at local scales.

Flowering plants have modified their floral organs in remarkably diverse ways to optimize their interaction with pollinators. Although floral organs represent a major source of floral diversity, many plants also use extrafloral organs, such as bracts and bracteoles, in interacting with pollinators; however, the evolutionary dynamics of non-floral organs involved in pollination are poorly studied. The genus Macaranga is characterized by protective mutualisms with ants that potentially interfere with pollinators on flowers. Macaranga flowers lack perianths and, notably, bracteoles serve the dual function of rewarding pollinators and protecting them from guarding ants; in one group of species, bracteoles provide a nectar reward to generalist pollinators, while in another group, bracteole “chambers” protect thrips or hemipteran pollinators that use these structures as feeding and breeding sites. We examined the diversity and evolutionary dynamics of inflorescence morphology in Macaranga, focusing on bracteoles. We recognized three inflorescence types based on examination of herbarium materials: Discoid-gland, which possess disc-shaped glands on the bracteole surfaces (including all the generalist-pollinated species); Enclosing, in which bracteoles cover flowers (including all the thrips- and hemipteran-pollinated species); and Inconspicuous, in which bracteoles are small, narrow or absent. Ancestral state reconstruction indicated that inflorescence morphologies have changed multiple times in the genus. These findings suggest that morphological changes in non-floral characters (bracteoles) of Macaranga species have occurred as frequently as in the floral structures of many flowering plants. The multiple evolutions of the Enclosing bracteoles, which protect pollinators, might have been facilitated by pollination interference from mutualistic ants.

In this Letter, we demonstrate that short-period stars orbiting around the supermassive black hole in our Galactic Center can successfully be used to probe the gravitational theory in a strong regime. We use 19 years of observations of the two best measured short-period stars orbiting our Galactic Center to constrain a hypothetical fifth force that arises in various scenarios motivated by the development of a unification theory or in some models of dark matter and dark energy. No deviation from General Relativity is reported and the fifth force strength is restricted to an upper 95% confidence limit of $\left|\alpha\right| < 0.016$ at a length scale of $\lambda=$ 150 astronomical units. We also derive a 95% confidence upper limit on a linear drift of the argument of periastron of the short-period star S0-2 of $\left|\dot \omega_\textrm{S0-2} \right|< 1.6 \times 10^{-3}$ rad/yr, which can be used to constrain various gravitational and astrophysical theories. This analysis provides the first fully self-consistent test of the gravitational theory using orbital dynamic in a strong gravitational regime, that of a supermassive black hole. A sensitivity analysis for future measurements is also presented., Comment: 8 pages, 3 figures, version accepted for publication in Phys. Rev. Letters. Original title "Seeking a fifth force with..." changed upon request of the PRL editors

Continually flowering plants bloom continuously throughout the year, as often seen in plants distributed along the roadsides or in the understory layers in Southeast Asia's tropical rain forests. Dillenia suffruticosa (Griff. ex Hook. f. & Thomson) Martelli (Dilleniaceae) is one such continually flowering shrub that flowers during periods of community-wide mass flowering, general flowering (GF), and non-GF. During irregularly occurring GF periods, when species of all forest layers flower synchronously for several months, some pollinators migrate to the canopy layer, where GF promotes the pollination success of participating plants. Continually flowering plants share the available pollinator community with GF plants, and the reproductive success of continually flowering plants may be affected during the GF period. To assess the effects of GF on the reproductive success of a diverse range of continually flowering plants, we examined the differences in pollinator density and reproductive success between GF and non-GF periods in D. suffruticosa at four different research sites. Although the seed set differed among the four research sites, pollinator density and fruit set did not differ between GF and non-GF periods or research sites. Our results suggest that the reproductive success of D. suffruticosa was maintained at an approximately constant level, regardless of the flowering phenology of the canopy layer or other vegetation components.