#Earliest tobacco use in Pacific Northwest discoverednative American hunter-gatherers living more than a thousand years ago in what is now northwestern California ate salmon acorns
Most soils in Malawi have extremely low levels of the selenium available to plant roots
The Sonoran Desert and Sky Islands ecoregion lies at the northern edge of the North american monsoon where vegetation ranges from saguaro-studded subtropical desert in the lowlands to high-altitude boreal forests.
New checklist brings information about cucurbitaceae up to datein 2010 it was shown that melons and cucumbers can be traced back to India.
Because of the importance of the region for an understanding of Cucurbitaceae evolution and diversity a new checklist of the Cucurbitaceae of India was produced to update the information on that family.
The cucumber Family cucurbitaceae includes many of our favorite foods: pumpkins melon cucumber watermelon bottle gourds and bitter gourd.
Molecular data have revealed recently that both cucumber (Cucumis sativus L) . and melon (Cucumis melo L.)are indigenous to India
and likely to have originated from the foothills of The himalayas. Arun Pandey from the Department of Botany University of Delhi India and Susanne Renner from the Departments of Systematic Botany and Mycology University of Munich Germany decided to produce a checklist of the Cucurbitaceae of India that would bring up-to date the information
available for that family. The list treats 400 relevant names and provides information on the collecting locations for all type specimens.
The list includes 94 species (10 of them endemic to India) from 31 genera. For each species the checklist provides distributional information electronic links to images of living or dried plants and information on publicly available DNA sequences.
The most species-rich genera are Trichosanthes with 22 species Cucumis with 11 (all but two wild) and the bitter gourd Genus momordica with eight.
The checklist also includes a phylogenetic reconstruction of the family that shows the DNA-based placement of the 31 Indian genera relative to the World's remaining Cucurbitaceae.
Updating and summarising the available information on Indian Cucurbitaceae and linking it to molecular data
Those droughts had major environmental and social effects Griffin said pointing out that the late-16th-century megadrought caused landscape-scale vegetation changes a 17th-century drought has been implicated in the Pueblo Revolt of 1680
Different vegetation models currently simulate remarkable variability in forest sensitivity to climate change. And while these new results suggest that tropical forests may be quite resilient to warming it is important also to remember that other factors not included in this study such as fire
and ice in the northern latitudes has diminished in recent years the temperature over the northern land mass has increased at different rates during the four seasons causing a reduction in temperature and vegetation seasonality in this area.
In other words the temperature and vegetation at northern latitudes increasingly resembles those found several degrees of latitude farther south as recently as 30 years ago.
The NASA-funded study based on newly improved ground and satellite data sets examines critically the relationship between changes in temperature and vegetation productivity in northern latitudes.
This created during the past 30 years large patches of vigorously productive vegetation totaling more than a third of the northern landscape--over 9 million km2
which is roughly about the area of the USA--resembling the vegetation that occurs further to the south says Dr. Compton Tucker Senior Scientist NASA's Goddard Space Flight Center Greenbelt Maryland.
Today just 30 years later it equals that of lands above 57 degrees north--a reduction in vegetation seasonality of about seven degrees south in latitude says co-author Prof.
and vegetation seasonality of about four to seven degrees of latitude during the past 30 years says co-author Eugenie Euskirchen Research Professor University of Alaska Fairbanks. The reduction of vegetation seasonality resulting in increased greenness
in the Arctic is visible on the ground as an increasing abundance of tall shrubs
This may portend a decoupling between growing season warmth and vegetation productivity in some parts of the North as the ramifications of amplified greenhouse effect--including permafrost thawing frequent forest fires outbreak of pest infestations
and summertime droughts--come in to play says co-author Hans Tømmervik Senior Researcher Norwegian Institute for Nature Research Tromsã¸Norway.
Any significant alterations to temperature and vegetation seasonality are likely to impact life not only in the north but elsewhere in ways that we do not yet know.
#Bees get a buzz from flower nectar containing caffeineyou may need a cup of coffee to kick start the day
but it seems honeybees also get their buzz from drinking flower nectar containing caffeine. Publishing in Science researchers have shown that caffeine improves a honeybee's memory
and citrus flowers were three times more likely to remember a flower's scent than those feeding on just sugar.
Remembering floral traits is difficult for bees to perform at a fast pace as they fly from flower to flower
and we have found that caffeine helps the bee remember where the flowers are. In turn bees that have fed on caffeine-laced nectar are laden with coffee pollen
and Coffea species often contained low doses of caffeine. They included'robusta'coffee species mainly used to produce freeze-dried coffee
Typically the nectar in the flower of a coffee plant contains almost as much caffeine as a cup of instant coffee.
and return to some flowers over others will help inform how landscapes could be managed better.
#A new cryptic spider species from Africathe species from the genus Copa are very common spiders found in the leaf litter of various habitats.
To capture the build up of pressure observed in actual maple stems we must also include the freezing process as well as multiple freeze/thaw cycles.
Why does a light snow cover around the trunk have such a big influence on stem pressures?
which allows potato plants to develop tubers during the long days of spring and summer in northern latitudes.
Wild potatoes which originate in the Andes of South america were brought to Europe by Spanish sailors in the late 16th century.
Naturally occurring near the Equator Andean potatoes develop tubers on days which are relatively shorter than those in high latitude summer.
and short nights native South american potato varieties would only begin making tubers in autumn when the days last 12 hours or less.
However modern potato varieties show a wide variation in the timing of tuber formation with early varieties starting as early as April.
The mutations in the newly discovered regulator of tuber formation allow potatoes to escape the original short day regulation mechanism suited to the Andes
The authors also describe a variety of mutations in the tuber formation regulator gene which occur in different combinations in modern potato cultivars giving rise to early medium
#Bats not bothered by forest fires, study findsa survey of bat activity in burned and unburned areas after a major wildfire in the southern Sierra nevada mountains found no evidence of detrimental effects on bats one year after the fire.
However some plants that are ideal for bioenergy production come with a drawback--they can potentially become invasive weeds that can cause billions of dollars in economic damage.
We did this analysis to draw attention to state noxious weed lists and to suggest ways to help prevent additional plants from escaping cultivation
Barney is an assistant professor of plant pathology physiology and weed science in the College of Agriculture and Life sciences.
According to our analysis current noxious weed laws do not provide adequate protection to prevent invasions in natural areas
Suggestions for Improved Regulation the authors also advocate liability for industry developers who fail to show due diligence in evaluating the potential invasiveness of a new cultivar.
This will help take the expense of noxious weed control away from taxpayers while protecting conscientious biofuels developers some of
and cultivation of 111 species of terrestrial aquatic and parasitic plants included on the Federal Noxious Weed List.
Noxious weeds on federal or state lists and invasive weeds are defined generally as plants with adverse social economic or ecological effects.
or federal noxious weed lists are subject to regulation. Since state departments of agriculture have responsibility for most regulatory bodies occasionally sharing responsibility with environmental agencies fewer plants that invade forests pastureland
The authors analyzed noxious and invasive weed species reports from each state and determined that official noxious plant lists contain on average only 19.6%of the species considered invasive by the IPCS and EPCS.
since funding for weed control is funneled generally into formally listed noxious plants. Because control is easiest in the early stages of infestation
when the political process involved in listing a weed may not have begun even the financial effects of this gap can be massive.
and more inclusive if revamped regulatory boards with input from invasive and exotic weed councils evaluated plants based on criteria such as the plant's history ecology reproductive potential and the potential for rapid spreading.
Barney earned his bachelor's degree in chemistry at the University of Kentucky and his master's and doctorate degrees in weed ecology at Cornell University.
He is a member of the Weed Science Society of America and the Ecological Society of America.
#Assembling the transcriptome of a noxious weed: New resources for studying how plants invadein order to build
Pankaj Jaiswal Assistant professor of Botany and Plant pathology at Oregon State university Samuel Fox a Postdoctoral Associate in Jaiswal's laboratory and colleagues assembled transcriptomes of a noxious weed Brachypodium sylvaticum
and is listed as a noxious weed along the West Coast of the United states. It is aggressively invasive within its current range--near monocultures of this grass occupy thousands of hectares of mixed coniferous understory
Fox and Cruzan note The seed and genomic resources are publicly available so it would be relatively easy for any research group to establish a research program focused on slender false brome.
University of Arizona geneticists have discovered the oldest known genetic branch of the human Y chromosome--the hereditary factor determining male sex.
The new divergent lineage which was found in an individual who submitted his DNA to Family tree DNA a company specializing in DNA analysis to trace family roots branched from the Y chromosome tree before the first appearance of anatomically modern humans in the fossil record.
because previously the most diverged branches of the Y chromosome were found in traditional hunter-gatherer populations such as Pygmies
whether it's switchgrass remnants of corn stalks fast-growing trees or algae. The traditional strategy had been a multistep approach involving sample dissolution and chromatographic analysis
NREL's Tool Combines Precision and Speedthe path toward an ultra-fast ultra-sophisticated screening tool went through Arborgen one of the nation's largest tree seedling suppliers.
not only for the pulp and paper industry but also for any business wishing to reduce its carbon footprint.
Application of dynamic models to estimate greenhouse gas emission by wastewater treatment plants of the pulp
In other layers soils and roots were just starting to develop when they were smothered with more ash.
and form part of the protective coating on seeds. Phytoliths vary in appearance under a microscope depending on the kind of plant.
Eighty-seven percent of the world's flowering plants including most of the leading global food crops are pollinated by animals.
Flowers mislead traditional taxonomyfor hundreds of years plant taxonomists have worked to understand how species are related.
And paramount among these morphological traits were aspects of flower shape and arrangement. In the papilionoid legumes--a large diverse group that includes the common pea
and bean--most species have specialized highly butterfly-shaped flowers with bilateral symmetry fused stamens and strongly differentiated standard wing
and keel petals. Papilionoid genera with radially symmetric or weakly differentiated flower parts have been regarded as primitive members of the group.
However an international team of researchers have found that floral morphologies may be less reliable than other traits in determining the relationships of papilionoid species and genera.
and the putatively related Sweetia as primitive papilionoid groups because they lack the characteristic papilionate flowers.
Yet evidence from DNA sequences suggested that these plants were closely related to two rainforest genera with true papilionate flowers Vatairea and Vataireopsis.
Despite their striking differences in flower shape Luetzelburgia Sweetia Vatairea and Vataireopsis turned out to be close relatives.
Moreover the two genera with papilionate flowers were not each other's closest relatives. According to Cardoso We showed that similarity in floral morphology does not predict phylogenetic relatedness.
Indeed genera with very different flower shapes are often very closely related (Luetzelburgia and Vatairea and genera with highly similar flowers share such similarity via convergent evolution (Vatairea and Vataireopsis).
For these plants other morphological characteristics may indicate relationships more reliably. Floral traits are apparently more prone to rapid evolutionary changes in response to local ecological conditions Cardoso said
the flowers might just be fooling us. Story Source: The above story is provided based on materials by American Journal of Botany.
These harsh coastal biomes are characterized by thick vegetation--particularly clusters of salt-loving mangrove trees
Recollecting 26 spring-blooming flowers from Robertson's network Knight Phd professor of biology at Washington University
Half the bee species associated with these flowers in Robertson's lifetime had disappeared some pollinators were active before their plants had bloomed plants weren't visited as often
Robertson's astonishing legacya professor of biology and Greek at Blackburn College in Carlinville Illinois Charles Robertson collected flower-visiting insects near Carlinville between 1887 and 1916.
Robertson's meticulous database is probably the oldest of its type for flower-visiting insects.
i. d. tags and his privately published book Flowers and Insects. How Robertson's network is studied doingrobertson it all Knight said.
If it was a species of flowering plant within a 10-mile radius of Carlinville it was in his study.
If any community is going to be affected by climate change Knight said it would be this one because the plants flower soon after the winter snow melts.
The flowers were in bloom eight fewer days on average and the insects flew for 22.5 fewer days.
Robertson didn't keep track of how much time he spent in the field watching each flower
One of the plants Marlin studied was Claytonia virginica commonly known as'spring beauty.''We were interested very in Claytonia virginica
because it is the plant in the network currently visited by the greatest diversity of bees Knight said.
Comparing the visitation rates we measured to Marlin's we discovered that the bees were making fewer trips to the flowers than they had in the 1970s.
and Knight picked six bee species that frequently visited Claytonia virginica two named by Robertson and washed Robertson's archival specimens of those bees Marlin's specimens and their own.
Since these were all the same species of bee caught off the same flower the default assumption was that they'd be covered in much the same pollen.
It turned out that these bees had been more loyal to Claytonia in the past than they were now.
The fraction of the pollen on the bee contributed by Claytonia virginica was highest in Robertson's time lower in Marlin's time and much lower in 2010.
and at worst can clog up pistils preventing fertilization the bee washings also pointed to a decline in pollination services.
and seed crops that make diets interesting such as tomatoes coffee and watermelon is limited because their flowers are pollinated not adequately says Harder.
We also show that adding more honey bees often does not fix this problem but that increased service by wild insects would help.
Flowers of most crops need to receive pollen before making seeds and fruits a process that is enhanced by insects that visit flowers.
These pollinators including bees flies butterflies and beetles usually live in natural or semi-natural habitats such as the edges of forests hedgerows or grasslands.
The study found that the proportion of flowers producing fruits was considerably lower in sites with fewer wild insects visiting crop flowers.
The authors examined the effect of GSSE processed from a grape cultivar('Carignan')of Vitis vinifera from northern Tunisia on rats.
and colleagues have identified a special population of adult stem cells in bone marrow that have the natural ability to migrate to the intestine
Because these therapies aren't always effective scientists hope to use stem cells to develop an injectable cell therapy to treat IBD.
The new research complements a 2012 report by Almeida-Porada's team that identified stem cells in cord blood that are involved in blood vessel formation
In the current study the team used cell markers to identify a population of stem cells in human bone marrow with the highest potential to migrate to the intestine
At 75 days post-gestation the researchers found that most of the transplanted cells were positioned in the crypt area replenishing the stem cells in the intestine.
Macroscopic remains of maize (kernels leaves stalks and cobs) were rare. However the team looked deeper and found an abundance of microscopic evidence of maize in various forms in the excavations.
Also modern soil samples consistently contain pollen from the Australian pine (Casuarinaceae Casuarina) a plant which is an invasive species from Australia never found in prehistoric samples.
In fact Z. mays was the second most common pollen found in the total of all samples behind only pollen from cattails which have wind-pollinated flowers.
The study was modeled after one conducted in a shrub-oak ecosystem in Colorado where scientists calculated a 180-meter ecological effect zone based on their results.
The tree tomatoa researcher at the UPM is collaborating in the characterization of genetic resource of the tree tomato to enhance its cultivation and commercialization in Andean and Mediterranean countries.
The tree tomato has a high potential for Andean cultivation but it is currently not well-utilized.
and the Universidad T cnica Particular de Loja (Ecuador) have detailed the morphology and genetic diversity of tree tomato.
The tree tomato (Solanum betaceum or Cyphomandra betacea) can reach up three meters of height and belongs to the Solonaceae family
and yellow orange or purple color with a pleasant-tasting slightly acidic aromatic pulp rich in vitamins and minerals.
and distinguish electric signals given out by flowers. Flowers often produce bright colours patterns and enticing fragrances to attract their pollinators.
Researchers at Bristol's School of Biological sciences led by Professor Daniel Robert found that flowers also have their equivalent of a neon sign--patterns of electrical signals that can communicate information to the insect pollinator.
These electrical signals can work in concert with the flower's other attractive signals and enhance floral advertising Power plants are charged usually negatively
and emit weak electric fields. On their side bees acquire a positive charge as they fly through the air.
No spark is produced as a charged bee approaches a charged flower but a small electric force builds up that can potentially convey information.
By placing electrodes in the stems of petunias the researchers showed that when a bee lands the flower's potential changes
and remains so for several minutes. Could this be a way by which flowers tell bees another bee has recently been visiting?
To their surprise the researchers discovered that bumblebees can detect and distinguish between different floral electric fields.
The discovery of such electric detection has opened up a whole new understanding of insect perception and flower communication.
Dr Heather Whitney a co-author of the study said: This novel communication channel reveals how flowers can potentially inform their pollinators about the honest status of their precious nectar and pollen reserves.
Professor Robert said: The last thing a flower wants is to attract a bee and then fail to provide nectar:
a lesson in honest advertising since bees are good learners and would soon lose interest in such an unrewarding flower.
The co-evolution between flowers and bees has a long and beneficial history so perhaps it's not entirely surprising that we are still discovering today how remarkably sophisticated their communication is.
The research was supported by the Leverhulme Trust. Story Source: The above story is provided based on materials by University of Bristol.
Researchers propose new theory on deep roots of human speechthe sounds uttered by birds offer in several respects the nearest analogy to language Charles darwin wrote in The Descent of Man (1871)
when looking for nectarflower colors that contrast with their background are more important to foraging bees than patterns of colored veins on pale flowers according to new research by Heather Whitney from the University of Cambridge in the UK and her colleagues.
Their observation of how patterns of pigmentation on flower petals influence bumblebees'behavior suggests that color veins give clues to the location of the nectar.
however that bees have an innate preference for striped flowers. The work is published online in Springer's journal Naturwissenschaften--The Science of Nature.
Very few flowers are a simple block of a single color. Patterns of pigmentation include color patterns within a petal or different colors on different petals.
These patterns are thought to be important for pollination. Bees can identify and are attracted sometimes to patterned flowers over plain flowers.
These patterns can increase the speed with which bees locate the nectar reward in a flower.
Venation patterns--or lines of color on flower petals--are common in Antirrhinum flowers commonly known as snapdragons.
The authors looked at the ways in which these color veins influence bumblebee foraging behavior.
They exposed bees who had seen not flowers before to veined ivory and red types of snapdragon flowers.
and veined flowers and which type of flower they preferred when they were looking for nectar.
From the bees'perspective red flowers reflected little light while red veins on ivory flowers slightly changed the color of the flower.
however had the most effect as it contrasted with the brown background more than the red flowers did.
and veined flowers but showed no preference for one or the other. In contrast both ivory and veined flowers were significantly more popular than red flowers.
The authors conclude: Venation patterns might be prevalent in nature because they can be useful nectar guides particularly
when they also increase flower visibility. But it appears that the color contrast of a flower with its background has a greater influence on bee preference.
Story Source: The above story is provided based on materials by Springer Science+Business Media. Note: Materials may be edited for content and length.
But Chuanbing Tang at the University of South carolina is developing new plastics that are green from the cradle to the grave.
Rather than tapping a barrel of oil to obtain starting materials Tang's research group
instead begins with the natural resins found in trees especially evergreens. The rosin and turpentine derived from their wood is rich in hydrocarbons similar but not identical to some components of petroleum.
Hydrocarbon-rich starting materials whether from petroleum or tree resin can be converted into various forms of
what are termed commonly plastics through polymerization. With petroleum derivatives scientists have invested more than a hundred years of research into refining the polymer chemistry involved
But processes for developing plastics from renewable sources such as rosin and turpentine are not nearly as developed.
Renewable polymers currently suffer from inferior performance in comparison to those derived from petroleum Tang said.
Tang just received a National Science Foundation CAREER award to further develop the polymer chemistry he has been refining
The award from NSF's Division of Materials Research will support Tang's laboratory through 2018.
and architectures dictate the properties of the materials we make Tang said. If we can establish clear structure-property relationships we will be able to achieve the kinds of results we now get from polymers made from petroleum.
According to Tang molecules derived from wood products are particularly worthwhile targets. They're a rich source of the cycloaliphatic
Most plastics from nonrenewable resources are generally not biodegradable Tang said. With a polymer framework derived from renewable sources we're able to make materials that should break down more readily in the environment.
Together with graduate student Perry Wilbon Tang worked with Fuxiang Chu of the Chinese Academy of Forestry to prepare the first comprehensive review of terpenes terpenoids
and rosin three components of tree resin (and other natural products as well) that are plentiful sources of cycloaliphatic and aromatic structures.
Published as the cover article in Wiley's Macromolecular Rapid Communications in January 2013 the review is a blueprint for just one approach that Tang is taking to develop sustainable polymers from the greenest of sources.
i e. to exclude anything that contains wheat rye or barley. Until the 1970s celiac disease was unusual
i e. to exclude anything that contains wheat rye or barley. Until the 1970s celiac disease was unusual
He found that shrubs such as willow and birch became the dominant plants in response to warming where the herbivorous animals were excluded from the ecosystem.
When these shrubs expand in the plant community they tend to shade their neighbors and the build up of leaf litter around the shrubs tends to cool the soil surface reducing the availability of soil nutrients for other plants Post said.
As a result shrubs can quickly out-compete other plants and reduce species diversity in the process.
On the other hand in those areas where caribou and musk ox were able to graze freely shrub responses to warming were muted
and species diversity within the plant community was maintained. Post said the take-home message from his study is that in a warming climate intact populations of large herbivores may be crucial to the maintenance of plant-community diversity and to the persistence of existing plant communities.
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