scholarly journals Geography is essential for reproductive isolation between florally diversified morning glory species from Amazon canga savannahs

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Elena Babiychuk ◽  
Juliana Galaschi Teixeira ◽  
Lourival Tyski ◽  
José Tasso Felix Guimaraes ◽  
Luiza Araújo Romeiro ◽  
...  
Keyword(s):  
Interspecific Hybridization ◽  
Climate Models ◽  
Flower Colour ◽  
Morning Glory ◽  
Temperate Climate ◽  
Postzygotic Isolation ◽  
Major Barrier ◽  
Flower Visitor ◽  
Native Bee ◽  
Floral Diversification

AbstractThe variety, relative importance and eco-evolutionary stability of reproductive barriers are critical to understanding the processes of speciation and species persistence. Here we evaluated the strength of the biotic prezygotic and postzygotic isolation barriers between closely related morning glory species from Amazon canga savannahs. The flower geometry and flower visitor assemblage analyses supported pollination by the bees in lavender-flowered Ipomoea marabaensis and recruitment of hummingbirds as pollinators in red-flowered Ipomoea cavalcantei. Nevertheless, native bee species and alien honeybees foraged on flowers of both species. Real-time interspecific hybridization underscored functionality of the overlap in flower visitor assemblages, questioning the strength of prezygotic isolation underpinned by diversification in flower colour and geometry. Interspecific hybrids were fertile and produced offspring in nature. No significant asymmetry in interspecific hybridization and hybrid incompatibilities among offspring were found, indicating weak postmating and postzygotic isolation. The results suggested that despite floral diversification, the insular-type geographic isolation remains a major barrier to gene flow. Findings set a framework for the future analysis of contemporary evolution of plant-pollinator networks at the population, community, and ecosystem levels in tropical ecosystems that are known to be distinct from the more familiar temperate climate models.

scholarly journals O8B.6 Occupational heat stress due to climate change: estimating future heat wave hazards

2019 ◽  
Vol 76 (Suppl 1) ◽  
pp. A73.2-A73
Author(s):  
Matthias Otto ◽  
Tord Kjellstrom ◽  
Bruno Lemke
Keyword(s):  
Climate Change ◽  
Heat Stress ◽  
Occupational Health ◽  
Health Effects ◽  
Heat Wave ◽  
Climate Models ◽  
Heat Waves ◽  
Grid Cell ◽  
High Heat ◽  
Temperate Climate

Exposure to extreme heat negatively affects occupational health. Heat stress indices like Wet Bulb Globe Temperature (WBGT) combine temperature and humidity and allow quantifying the climatic impact on human physiology and clinical health. Multi-day periods of high heat stress (aka. heat waves) affect occupational health and productivity independently from the absolute temperature levels; e.g. well-documented heat-waves in Europe caused disruption, hospitalisations and deaths (2003 French heat wave: more than 1000 extra deaths, 15–65 years, mainly men) even though the temperatures were within the normal range of hotter countries.Climate change is likely to increase frequency and severity of periods of high heat stress. However, current global grid-cell based climate models are not designed to predict heat waves, neither in terms of severity or frequency.By analysing 37 years of historic daily heat index data from almost 5000 global weather stations and comparing them to widely used grid-cell based climate model outputs over the same period, our research explores methods to assess the frequency and intensity of heat waves as well as the associated occupational health effects at any location around the world in the future.Weather station temperature extreme values (WBGT) for the 3 hottest days in 30 years exceed the mean WBGT of the hottest month calculated from climate models in the same grid-cell by about 2 degrees in the tropics but by 10 degrees at higher latitudes in temperate climate regions.Our model based on the relationship between actual recorded periods of elevated heat-stress and grid-cell based climate projections, in combination with population and employment projections, can quantify national and regional productivity loss and health effects with greater certainty than is currently the case.

Global Changes of Köppen-Trewartha Climate Zones Derived from RegCM CORDEX-CORE Simulations

2020 ◽  
Author(s):  
Michal Belda ◽  
Tomáš Halenka
Keyword(s):  
Climate Models ◽  
Added Value ◽  
Temperate Climate ◽  
Global Changes ◽  
Vegetation Zone ◽  
Climate Type ◽  
Temperature And Precipitation ◽  
Driving Model ◽  
Dry Climates ◽  
The Individual

<p><span>The analysis of climate patterns can be performed for each climatic variable separately or the data can be aggregated using e.g. a kind of climate classification. The advantage of such method, in our case Köppen-Trewartha classification, is putting together the most important variables, i.e. temperature and precipitation, considering not only annual means, but through monthly values the annual cycle as well. These classifications usually correspond to vegetation distribution in the sense that each climate type is dominated by one vegetation zone or eco-region. Climate classifications represent a convenient tool for the assessment and validation of climate models and for the analysis of simulated future climate changes.</span></p><p> </p><p><span>The results of RegCM driven by selected CMIP5 simulations (mostly HadGEM, MPI and NorESM) produced within the CORDEX-CORE experiment over nine CORDEX domains are analysed. Validation based on ERA-Interim driven runs compared to CRU database (E-OBS for higher resolution in Europe) shows reasonable agreement in the Northern hemisphere with a tendency towards wetter and colder climate types in North America. Worse representation in Southern hemisphere is observed, mainly in Australia (lack of desert type). Through the analysis of the control experiments together with the performance of driving GCMs we can assess the sources of the biases in present conditions as well as the added value, which comes mainly from better representation of topography in higher resolution and thus appearance of mountaineous tundra type, as well as better representation of coastal regions and thus separating maritime subtypes. Finally, for two scenarios RCP8.5 and RCP2.6 we show the projections of the individual types‘ area changes, mainly decline of boreal and polar types, their shift to the higher latitudes and altitudes, increase of temperate, subtropical and dry climates. Magnitude, </span><span>and in some cases (temperate climate) even the sign</span><span> of change is largely dependent on the region and driving model.</span></p>

scholarly journals Comparative transcriptomics between Drosophila mojavensis and D. arizonae reveals transgressive gene expression and underexpression of spermatogenesis-related genes in hybrid testes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Cecilia A. Banho ◽  
Vincent Mérel ◽  
Thiago Y. K. Oliveira ◽  
Claudia M. A. Carareto ◽  
Cristina Vieira
Keyword(s):  
Gene Expression ◽  
Gene Regulation ◽  
Genetic Distance ◽  
Candidate Genes ◽  
Interspecific Hybridization ◽  
Divergence Time ◽  
Drosophila Mojavensis ◽  
Postzygotic Isolation ◽  
Differential Gene ◽  
Interspecies Hybrid

AbstractInterspecific hybridization is a stressful condition that can lead to sterility and/or inviability through improper gene regulation in Drosophila species with a high divergence time. However, the extent of these abnormalities in hybrids of recently diverging species is not well known. Some studies have shown that in Drosophila, the mechanisms of postzygotic isolation may evolve more rapidly in males than in females and that the degree of viability and sterility is associated with the genetic distance between species. Here, we used transcriptomic comparisons between two Drosophila mojavensis subspecies and D. arizonae (repleta group, Drosophila) and identified greater differential gene expression in testes than in ovaries. We tested the hypothesis that the severity of the interspecies hybrid phenotype is associated with the degree of gene misregulation. We showed limited gene misregulation in fertile females and an increase in the amount of misregulation in males with more severe sterile phenotypes (motile vs. amotile sperm). In addition, for these hybrids, we identified candidate genes that were mostly associated with spermatogenesis dysfunction.

scholarly journals Changes in Köppen-Geiger climate types under a future climate for Australia: hydrological implications

2012 ◽  
Vol 16 (9) ◽  
pp. 3341-3349 ◽  
Author(s):  
R. S. Crosbie ◽  
D. W. Pollock ◽  
F. S. Mpelasoka ◽  
O. V. Barron ◽  
S. P. Charles ◽  
...  
Keyword(s):  
Climate Change ◽  
Water Resources ◽  
Climate Models ◽  
Global Climate ◽  
Global Climate Models ◽  
Cold Climate ◽  
Future Climate ◽  
Temperate Climate ◽  
Climate Change Scenarios ◽  
Australian Continent

Abstract. The Köppen-Geiger climate classification has been used for over a century to delineate climate types across the globe. As it was developed to mimic the distribution of vegetation, it may provide a useful surrogate for making projections of the future distribution of vegetation, and hence resultant hydrological implications, under climate change scenarios. This paper developed projections of the Köppen-Geiger climate types covering the Australian continent for a 2030 and 2050 climate relative to a 1990 historical baseline climate using 17 Global Climate Models (GCMs) and five global warming scenarios. At the highest level of classification for a +2.4 °C future climate (the upper limit projected for 2050) relative to the historical baseline, it was projected that the area of the continent covered by – tropical climate types would increase from 8.8% to 9.1%; – arid climate types would increase from 76.5% to 81.7%; – temperate climate types would decrease from 14.7% to 9.2%; – cold climate types would decrease from 0.016% to 0.001%. Previous climate change impact studies on water resources in Australia have assumed a static vegetation distribution. If the change in projected climate types is used as a surrogate for a change in vegetation, then the major transition in climate from temperate to arid in parts of Australia under a drier future climate could cause indirect effects on water resources. A transition from annual cropping to perennial grassland would have a compounding effect on the projected reduction in recharge. In contrast, a transition from forest to grassland would have a mitigating effect on the projected reduction in runoff.

scholarly journals Visualizing Current and Future Climate Boundaries of the Conterminous United States: Implications for Forests

Forests ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 280 ◽  
Author(s):  
Brice Hanberry ◽  
Jacob Fraser
Keyword(s):  
United States ◽  
Climate Models ◽  
Future Climate ◽  
Temperate Climate ◽  
Climate Projections ◽  
Subtropical Climate ◽  
Spatial And Temporal Scales ◽  
Ecological Boundaries ◽  
Current Climate ◽  
Plant Hardiness

Many potential geographic information system (GIS) applications remain unrealized or not yet extended to diverse spatial and temporal scales due to the relative recency of conversion from paper maps to digitized images. Here, we applied GIS to visualize changes in the ecological boundaries of plant hardiness zones and the Köppen-Trewartha classification system between current climate (1981–2010) and future climate (2070–2099), as well as changing climate within stationary state boundaries of the conterminous United States, which provide context for the future of forests. Three climate models at Representative Concentration Pathway (RCP) 8.5 were variable in climate projections. The greatest departure from the current climate in plant hardiness zones, which represent the coldest days, occurred where temperatures were coldest, whereas temperatures in the southeastern United States remained relatively stable. Most (85% to 99%) of the conterminous US increased by at least one plant hardiness zone (5.6 °C). The areal extent of subtropical climate types approximately doubled, expanding into current regions of hot temperate climate types, which shifted into regions of warm temperate climate types. The northernmost tier of states may generally develop the hottest months of the southernmost tier of states; Montana’s hottest month may become hotter than Arizona’s current hottest month. We applied these results to demonstrate the large magnitude of potential shifts in forested ecosystems at the end of the century. Shifts in ecological boundaries and climate within administrative boundaries may result in mismatches between climate and ecosystems and coupled human–environment systems.

scholarly journals Changes in Köppen-Geiger climate types under a future climate for Australia: hydrological implications

2012 ◽  
Vol 9 (6) ◽  
pp. 7415-7440 ◽  
Author(s):  
R. S. Crosbie ◽  
D. W. Pollock ◽  
F. S. Mpelasoka ◽  
O. V. Barron ◽  
S. P. Charles ◽  
...  
Keyword(s):  
Climate Change ◽  
Water Resources ◽  
Climate Models ◽  
Global Climate ◽  
Global Climate Models ◽  
Cold Climate ◽  
Future Climate ◽  
Temperate Climate ◽  
Climate Change Scenarios ◽  
Australian Continent

Abstract. The Köppen-Geiger climate classification has been used for over a century to delineate climate types across the globe. As it was developed to mimic the distribution of vegetation it may provide a useful surrogate for making projections of the future distribution of vegetation, and hence resultant hydrological implications, under climate change scenarios. This paper developed projections of the Köppen-Geiger climate types covering the Australian continent for a 2030 and 2050 climate relative to a 1990 historical baseline climate using 17 Global Climate Models (GCMs) and five global warming scenarios. At the highest level of classification for a +2.4 °C future climate (the upper limit projected for 2050) relative to the historical baseline, it was projected that the area of the continent covered by: – Tropical climate types would increase from 8.8% to 9.1% – Arid climate types would increase from 76.5% to 81.7% – Temperate climate types would decrease from 14.7% to 9.2% – Cold climate types would decrease from 0.016% to 0.001%. Previous climate change impact studies on water resources in Australia have assumed a static vegetation distribution. If the change in projected climate types is used as a surrogate for a change in vegetation, then the major transition in climate from Temperate to Arid in parts of Australia under a drier future climate could cause indirect effects on water resources. For a transition from annual cropping to perennial grassland this would have a compounding effect on the projected reduction in recharge. In contrast, a transition from forest to grassland would have a mitigating effect on the projected reduction in runoff.

scholarly journals Quantitation of DNA of Propidium Iodide-stained Nuclei from Ipomoea Species and Sweetpotato Using DNA Flow Cytometry

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 612c-612
Author(s):  
J.R. Bohac
Keyword(s):  
Flow Cytometry ◽  
Propidium Iodide ◽  
Dna Content ◽  
Ipomoea Batatas ◽  
Colchicine Treatment ◽  
Morning Glory ◽  
Dna Flow Cytometry ◽  
Uv Detector ◽  
Major Barrier ◽  
Ipomoea Species

Sweetpotato, Ipomoea batatas is in the morning glory family, Convolvulaceae, genus Ipomoea, group Batatas. It has many wild Ipomoea relatives that serve as a reservoir of many needed pest and stress-resistance genes. A major barrier to introgression of useful genes is the ploidy gap—sweetpotato is a hexaploid and wild Ipomoeas are diploids and tetraploids. The wild species can be successfully crossed using 2n pollen or by first increasing ploidy by colchicine treatment. The ploidy of such hybrid offpsring can be determined by DNA flow cytometry. My objective was to develop a technique to determine DNA content in Ipomoea and values for DNA content for the major Ipomoea species using the EPIC flow cytometer with a UV detector. Nuclei were extracted and pretreated with cellulase and pectolyase before staining with propidium iodide (PI). A highly linear relationship was found between the DNA content determined by DNA flow cytometry and the ploidy of the closest sweetpotato relatives as determined by chromosome counts. These species were diploid I. trifida, tetraploid I. batatas, and hexaploid I. batatas. DNA content was most similar among other diploid Ipomoea species in the group Batatas and was significantly different in other Ipomoeas not in group Batatas.

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