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SurveillanceEuropean Court of Justice: U.S. data systems expose users to state surveillance
The European Court of Justice (ECJ) in Luxembourg has ruled that U.S. digital data storage systems fail to provide sufficient privacy from state surveillance. The ECJ declared the American so-called safe harbor scheme "invalid." The ruling, which is binding on all EU members states, stated that: "The United States … scheme thus enables interference, by United States public authorities, with the fundamental rights of persons…" The ruling will have far-reaching ramifications for the online industry and would likely lead many companies to relocate their operations.
Personal protective equipmentClothing that guards against chemical warfare agents
Recent reports of chemical weapons attacks in the Middle East underscore the need for new ways to guard against their toxic effects. Scientists report that a new hydrogel coating that neutralizes both mustard gas and nerve agent VX. It could someday be applied to materials such as clothing and paint.
First response technologyDHS recruits Silicon Valley entrepreneurs to develop first-response technology
DHS wants better technology for first responders — police, firefighters, and EMTs — but rather than pushing for innovation from within the massive corporations that already provide technology to government agencies, the DHS has come to Silicon Valley to tap the entrepreneurial ecosystem of northern California. Giant technology firms have resources of large scale manufacturing and distribution, but there is one crucial difference. Technology startups are much more nimble, and can shift their development much faster than the huge corporations can.
EncryptionApple's encryption prevents it from complying with U.S. court order
Apple said it could not comply with a court order to hand over texts sent using iMessage between two iPhones because the company's encryption system makes it impossible to do so. The Justice Department persuaded the court to issue the order to facilitate an investigation involving guns and drugs. Legal experts say this is the first known direct face-off between the U.S. government and Apple over encryption. The FBI contends that such encryption puts the American public at risk because it makes it harder, if not impossible, to track and catch terrorists, pedophiles, and other criminals.
ForensicsDetermining the age of fingerprints
Watch the imprint of a tire track in soft mud, and it will slowly blur, the ridges of the pattern gradually flowing into the valleys. Researchers have tested the theory that a similar effect could be used to give forensic scientists something they've long wished for: A way to date fingerprints. Even the approximate age of a fingerprint can have a critical bearing on forensic results, as it can rule out some prints as being too old to be relevant to a crime scene. Military forensics experts would like to be able to date the multitude of fingerprints found on improvised bombs used by insurgents to winnow out prints of individuals who may simply have handled the components in a shop from those of the actual bombmakers.
Law-enforcement technologyPrepaid card reader helps law enforcement in seizing fraudulent cards
During arrests of criminal couriers, law enforcement officers rarely find bundles of cash wrapped in rubber bands anymore. Instead, they find stacks of plastic cards — bank credit and debit cards, retail gift cards, library cards, hotel card keys, even magnetic-striped Metrorail cards — which have been turned into prepaid cards. DHS S&T's Electronic Recovery and Access to Data (ERAD) Prepaid Card Reader is a small, handheld device which uses wireless connectivity to allow law enforcement officers in the field to check the balance of cards. This allows for identification of suspicious prepaid cards and the ability to put a temporary hold on the linked funds until a full investigation can be completed.
Law-enforcement technologyInternet technology to aid police, courts, prisons – but privacy issues must be addressed
New Internet-based technology may aid criminal justice agencies through tools such as better criminal databases, remotely conducted criminal trials, and electronic monitoring of parolees in the community, according to a new study. "The criminal justice field has mostly been reactive to new technology developments such as smart phones and social media," said the lead author of the report. "We've developed a road map of how new Internet-based technologies might help law enforcement in the future, as well as set priorities for the improvements that are needed most."
Visual-information gatheringSandia teams with industry to improve human-data interaction
Intelligence analysts working to identify national security threats in warzones or airports or elsewhere often flip through multiple images to create a video-like effect. They also may toggle between images at lightning speed, pan across images, zoom in and out or view videos or other moving records. These dynamic images demand software and hardware tools that will help intelligence analysts analyze the images more effectively and efficiently extract useful information from vast amounts of quickly changing data. Sandia Lab and EyeTracking, Inc. will research and develop tools to improve how intelligence analysts gather visual information.
SurveillanceBill requiring Internet companies to report "terrorist activity" opposed by digital rights groups
A coalition of digital rights groups and trade associations last week released a joint letter opposing a proposal in the Senate to require U.S. tech firms to police the speech of their users and to report any signs of apparent "terrorist activity" to law enforcement. The letter says that this sweeping mandate covers an undefined category of activities and communications and would likely lead to significant over-reporting by communication service providers. The letter urged senators to remove the "terrorist activity" reporting requirements from the Intelligence Authorization Act (S. 1705).
SurveillanceNSA to destroy millions of American call records collected under controversial program
The director of national intelligence said on Monday that the NSA would no longer examine call records collected by the NSA in its controversial bulk collection program before the June reauthorization of the Patriot Act which prohibits such collection. Bulk records are typically kept for five years, but the director said that although the records in the NSA database were collected lawfully, they would not be examined, and would soon be destroyed.
CybersecurityJournalists' computer security tools lacking in a post-Snowden world
Edward Snowden's leak of classified documents to journalists around the world about massive government surveillance programs and threats to personal privacy ultimately resulted in a Pulitzer Prize for public service. Though Snowden had no intention of hiding his identity, the disclosures also raised new questions about how effectively news organizations can protect anonymous sources and sensitive information in an era of constant data collection and tracking. Researchers found a number of security weaknesses in journalists' and news organizations' technological tools and ad-hoc workarounds.
SurveillanceIn first case of its kind, UK high court rules surveillance law unconstitutional
Controversial surveillance legislation hustled through parliament last summer has been ruled unlawful by the U.K. High Court, which argued that the vague terms and descriptions of powers in the Data Retention and Investigatory Powers Act 2014 (DRIPA) renders the act incompatible with human rights under European law. DRIPA, one in a series of laws supporting controversial surveillance powers passed by successive U.K. governments, establishes the principle by which anti-terrorism measures and national security priorities take precedence over human rights considerations. However, the judgment rules that the EU Charter of Fundamental Rights must take precedence, and in doing so requires the U.K. government to undo its own act of parliament — a significant precedent by a British court.
BiometricsFingerprint accuracy stays the same over time: Study
Fingerprints have been used by law enforcement and forensics experts to successfully identify people for more than 100 years. Though fingerprints are assumed to be infallible personal identifiers, there has been little scientific research to prove this claim to be true. As such, there have been repeated challenges to the admissibility of fingerprint evidence in courts of law. A new study shows that fingerprint recognition accuracy remains stable over time – and that the fingerprint recognition accuracy does not change even as the time between two fingerprints being compared increases.
Law enforcement technologyDetecting illegal, designer drugs from a single fingerprint
An innovative technology can detect the presence of a range of illegal and designer drugs from a single fingerprint, which could be a valuable new tool in bringing drug dealers and other criminals to justice. The technology, known as Matrix Assisted Laser Desorption Ionization Mass Spectrometry Imaging (MALDI-MSI), can detect the presence of cocaine, THC (the chemical present in marijuana), heroin, amphetamine and other designer drugs from a fingerprint.
SurveillanceNew U.K. surveillance review calls for a fresh start in the law for interception of communications
After a year of investigation and consultation, the U.K. Independent Surveillance Review has delivered its conclusions to Prime Minister David Cameron. The authors presented their report, A Democratic License to Operate, yesterday (14 July 2015). The Review shows how a democracy can combine the high level of security the public has a right to expect, and also ensure the respect for privacy and freedom of speech that are the foundations of a democracy. The panel unanimously calls on government, civil society, and industry to accept its recommendations and work together to put them into practice.
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Clattenburg and many rival managers, including Ferguson, were shocked by Chelsea's accusation that he used racist langauge towards Mikel last weekend.
"It's a free country where everybody has freedom of speech. We take into consideration what other people say and use it as a motivational tool for ourselves. It is a free country, as I say, and everybody can say what they want. He [Ferguson] likes to talk about other clubs; we tend not to. I'll leave it up to him," the Italian said.
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Who of Europe's top strikers will move to England this summer?
After a dreadful start to their Bundesliga campaign, Borussia Dortmund appear to have weathered the storm after going five matches without defeat.

subset: commoncrawl


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WLSC started in 1996 as a club (travel) soccer organization. A few years later, it was apparent that recreational soccer was something that was desired in our area. The recreational division of the club began in 1999, and shortly thereafter, the travel division was renamed Glass City Soccer.
We are a volunteer operated program, primarily serving the children of Washington Local Schools, West Toledo, Point Place and Erie, Michigan. Our focus is on helping children learn the fundamentals of soccer in a positive, educational environment.
Our league games are played on six Saturdays every Spring and Fall. All games are played on the fields adjacent to Shoreland Elementary. While parking can be tight and the fields are full, it makes for a festive environment every Saturday morning.
An Educational Experience in a Tournament Atmosphere
We will have between 7-9 fields all playing at the same time. In that sense, it's like a mini-tournament every weekend.
Record Growth in Recent Years
Our club continues to grow. In 2014, we had over 500 participants in the Spring, and over 400 in the Fall. As you can imagine, with this many players it takes many volunteers to make this league successful each year. For just one season, WLSC has the need for the following:
- Over 70 volunteer coaches
- Between 10-15 referees
- 36-40 concessions volunteers
When registering your child this season, please consider becoming either a volunteer coach (we understand it's not for everyone) or a concessions volunteer (just 40 volunteers at 1 hour each is all we need).
Some other things we thought you would like to know!
- Our games are played on Saturday Mornings between 9 AM and 1 PM, on the fields directly behind Shoreland Elementary School.
- Every child is welcome to play in our league, regardless of where they live or go to school.
- We are not directly affiliated with the Washington Local School District, which means all children are welcome to participate, regardless of where they attend school.
- Coaches, not league administration, determine the time, location, and duration of their team practices.
- We have a concession stand on-site every Saturday morning, selling snacks, drinks, and WLSC Spiritwear.
- Our referees are trained on the Laws of the Game by a USSF Certified Referee before the season. We currently have two referees who are USSF Certified on our staff.
- Our club works directly with Glass City Soccer, which is a competitive club that competes in the Northwest Ohio Youth Soccer League (NWOYSL). If your child shows signs of wanting to move to the next level of competition, we can put you in touch with their coaching staff and move you toward to process of playing travel soccer.
- We do our very best to make the teams as evenly matched as possible each season. A lot of time and work goes into registering players and assigning teams so that each participant has a high quality experience.
- Game lengths vary based on the age of the players. Our U-5 teams play 32 minute games, while our U-14 teams play 50 minute games.


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Direct Push Companies in Denmark
Columbia Steel Casting Co., Inc.
based in Portland, OREGON (USA)
Founded in 1901, Columbia Steel is a worldwide leading manufacturer of steel alloy and iron alloy impact, wear and heat resistant replacement parts for basic industry. Industries served include: aggregate, hard rock mining, dragline mining, metal recycling (shredding), cement manufacturing, coal-fired power, and more. Columbia Steel employees work closely with customers ...
Mierij Meteo Nederland
based in De Bilt, NETHERLANDS
Mierij Meteo systems was founded in 1982 and delivers solutions for projects where meteorological information is essential. Mierij Meteo is an innovating company that keeps innovating their meteorological sensors and systems with the goal to improve the quality of your measurements, to improve your saftey, to reduce your cost of ownership, to improve reliability and to ...
Geoprobe Systems
based in Salina, KANSAS (USA)
Geoprobe Systems manufactures machines, tools, and site remediation equipment for the environmental, geotechnical and mineral exploration industries. Geoprobe rigs are compact, high-capacity machines with options for augering, rotary drilling, rotary sonic, monitoring well installation, and subsurface sampling. Geoprobe Systems also designs and manufactures soil, ...
Rig Source, Inc. (RSI)
based in Elburn, ILLINOIS (USA)
Rig Source is a sales and rental center for new and used drill rigs, crawler carriers and support equipment within the core drill, oil and gas, geotechnical, environmental, pipeline and general construction industries. We offer a large variety of brands including: Geoprobe, Atlas Copco, CME, Diedrich, Mobile, Schramm , Acker, Boart Longyear, Mobile, Morooka, IHI, ...
Bioscience, Inc.
based in Allentown, PENNSYLVANIA (USA)
Bioscience, Inc., has been a trusted partner in the field of waste and wastewater treatment and monitoring worldwide for nearly 30 years. Founded in 1984, the Pennsylvania firm specializes in the application of custom microbial cultures for the biological processing of waste, as well as the manufacture of specialized instruments and test kits for wastewater analysis. ...
Groundwater Supply Co., Inc.
based in Sterling, MASSACHUSETTS (USA)
Groundwater Supply Co., Inc. is the largest stocking water well & environmental drilling supply warehouse in New England. Groundwater Supply Co., Inc `The Drill Store` is your one stop shop for anything and everything for waterwell and geothermal drilling.
based in jouars pontchartrain, FRANCE
Soil pollution,environment issues,ground, water and gas sampling remediation services throughout the European continent. We focus at two main techniques: direct push injections (biological and chemical) with various Geoprobe rigs
Tries GmbH & Co. KG
based in Ehingen, GERMANY
The ability to come up with ideas and turn them into reality that is what sets us humans apart from all other creatures on this planet. TRIES in Ehingen has been developing and producing hydraulic elements since 1964. Back then, just as today, resourceful engineers create well-engineered, functional products to the highest technological standards. At TRIES, ...
based in Noerresundby, DENMARK
DESMI is a global company specialised in the development and manufacture of pump solutions for marine, industry, oil spill combating, defence & fuel and utility both locally and globally. Our product range supplemented with agency products from other leading, world class manufacturers – is completed by related services such as the design and installation of pump plants, ...
Directional Technologies, Inc.
based in Wallingford, CONNECTICUT (USA)
Directional Technologies is the nation's expert horizontal remediation well drilling contractor. The company specializes in installation and design of horizontal remediation well systems. The company provides planning, review, well screen design and well development. The company began installing horizontal remediation wells in 1993 and installed the first horizontal ...
Need help finding the right suppliers?
Let the XPRTs do the work for you


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'Events' Archives
"Rock Docs" Film Festival – UCSB Professor David Novak Guests on "The Freak Power Ticket" (Monday, April 4th)
Later today, Monday, April 4th, from 11am until noon, Ted Coe, host of "The Freak Power Ticket," will be joined by guest David Novak, an Assistant Professor at UCSB whose field is Ethnomusicology. Mr. Novak will be discussing a class he is teaching this spring on "rock'n'roll documentaries" that will include free public screenings on Monday [...]
KCSB Spring Orientation Tuesday, April 5th at 6:30pm
Want to get involved? Be a DJ, news reporter, or sportscaster! KCSB will hold its spring orientation on Tuesday, April 5th at 6:30pm in Girvetz Hall 1004 on the UCSB campus. Here's a link to a campus map. Hope to see you there! KCSB Staff
Musical Charis & Blvd Park Play Monday, March 7th (on KCSB's "Freak Power Ticket" 11am-noon & at The Mercury Lounge at 8pm)
Two native California bands, Musical Charis (Fun, Dr. Seussical Indie Pop from Sacramento, CA), and Blvd Park (Americana, Roots/Folk, Spaghetti Western desert sound, originally from Sacramento, CA, recently relocated to Seattle), will be journeying on their "New American Dream Tour" during March and April, playing original music in over 60 [...]
KCSB Supports Lucky Dragons Performance at SB Contemporary Arts Forum on Thursday, February 3rd
The Santa Barbara Contemporary Arts Forum's "Forum Lounge" series presents Lucky Dragons, a music-and-art melding collective on Thursday, February 3 at 7pm. Lucky Dragons' performance will openly engage the audience and passersby in the creation of experimental, experience-rich artwork and music. What results from this collaborative [...]
Blues at the Crossroads: UCSB A&L Concert on Monday, January 31st Supported by KCSB
UCSB Arts & Lectures presents Blues at the Crossroads: The Robert Johnson Centennial Concert on Monday, January 31st, at 8pm in UCSB's Campbell Hall. Straight from the heart of the back country: Blues at the Crossroads picks up at the intersection where, as legend has it, delta blues musician Robert Johnson made a deal with a devil, giving up [...]
KJUC Winter Schedule
Here is the KJUC Winter Schedule. Congratulations to those who got on. As for the rest, come back in spring! We look forward to a great KJUC season. KJUC Winter Schedule Sincerely, Jordan and Raisa
NYC Musician Jim Thomson Joins "The Freak Power Ticket" (Monday, 11am-noon) Before Mercury Lounge Performances with Colin L. Orchestra & CSC Funk Band on Tuesday
Later today, Monday, January 10th, from 11am until noon, Ted Coe, host of "The Freak Power Ticket," will be joined by guest James Stacy Thomson, a drummer/percussionist (GWAR, The Alter Natives, Bio Ritmo, and more), DJ ("Das Booty"), record label boss, and actor from New York City. On Tuesday night, January 11th, two NYC-based bands [...]
Get Involved with KCSB!
KCSB Winter Quarter Orientation: KCSB provides community-access media training, and the public is invited to our Orientation scheduled for Tuesday, January 11, 2011, starting at 6 p.m., at the Life Sciences Building, Room 1001. Life Sciences is on UCen Road, near the Anacapa Residence Hall, on the UCSB campus. (Coming from off-campus? Remember to [...]
Bus Ad Spotted on the Eastside!
Hilary, a local KCSB listener and supporter, spotted the ad on the 2 bus on the east side! The grass on the lower half of the image is there by chance, KCSB is not being greenwashed, don't worry. Check it out!
KCSB Bus Ad Spotted!
Avid KCSB listener and volunteer spotted our bus ad this week! She gets a sweet free KCSB mug! Check it out!


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Chevy Chase News
Local news for Chevy Chase, MD continually updated from thousands of sources on the web.
Penn State Love Stories 2015-16: Part 7
Yesterday | Onward State | Comment?
MISSING: 58-year-old Chevy Chase woman
Wednesday | WUSA-TV Washington | Comment?
Surgery: Diverse interventions
Wednesday Oct 7 | Nature | Comment?
Here's Why You Don't Need to Shower With Soap
Tuesday Oct 6 | Health.com | Comment?
10 Eagle Scout survival skills everyone should know
Monday Oct 5 | Silicon Alley Insider | Comment?
Supreme Court to decide on hearing Huguely appeal in Yeardley Love death
Monday Oct 5 | The Baltimore Sun | Comment?
Should prostitution be less illegal-or more?
Legislation 168
American Terrorism: Plain and Simple
terrorism 1,264
28 Famous Co-Stars Who Totally Hated Each Other
Montgomery Co. board of elections accused of voter suppression, a secret phone callsa
Thursday Oct 1 | WTOP-FM Washington | Comment?
State Democrats to fight shift of Montgomery early voting sites
Wednesday Sep 30 | The Washington Post | Comment?
Proposal to build apartments atop new fire station sparks debate in Bethesda
Sunday Sep 27 | The Washington Post | Comment?
Republican-led Montgomery election board shifts early voting sites
Tuesday Sep 22 | The Washington Post | Comment?
Underwriting manager Schinnerer announces new president
Monday Sep 21 | Business Insurance | Comment?
Suspects Arrested in 'Pack-Style' Robberies at Bloomingdale's
Monday Sep 14 | Patch.com | Comment?
Oriental rugs are back
Monday Sep 14 | TwinCities | Comment?
Stress-less at MiRe Yoga
Friday Sep 11 | Washington Blade | Comment?
As Jewish New Year nears, a young congregation has its first Torah
Thursday Sep 10 | The Washington Post | Comment?
Updated: Fri Oct 09, 2015 04:20 am
Copyright © 2015 Topix LLC


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Save the Date for Digital Graffiti 2016Sep. 28 2015
The Alys Foundation is proud to announce the dates and exciting changes coming to the ninth annual Digital Graffiti at
Alys Beach affords families and friends a dream getaway. Easily accessible by car or a convenient flight into the Northwest Florida Beaches International Airport (ECP), once you arrive you'll feel like you're worlds away. At Alys Beach escaping is an art form and once guests see the iconic butteries and towering palms lining the entrance, there is an instant sense of escape.
The bright open spaces, alluring views, welcoming courtyards, relaxing sounds of trickling water from meticulously designed water features and refreshing coastal breezes make Alys Beach a haven for those seeking an escape.
With the pristine, white sand beaches a short walk from the vacation rentals and an abundance of Alys Beach amenities available to guests, a vacation in Alys Beach is a time of simplicity, beauty, reconnection, relaxation, and exploration. And when it is time to return home, you only leave footprints in the sand but you'll take memories that last a lifetime.
The Alys Foundation is proud to announce the dates and exciting changes coming to the ninth annual Digital Graffiti at
The 2015 Alys Beach 5K & 1 Mile Fun Run race results are in: 2015 Alys Beach 5K & 1


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School Board revises bereavement policy
Published: Wednesday, June 11, 2008 at 3:00 p.m.
Last Modified: Wednesday, June 11, 2008 at 11:40 a.m.
HOUMA -- School employees must now use sick days if they want to take time off to attend the funeral for a family member or fellow worker.
The Terrebonne Parish School Board revised its policy on bereavement days during a June 3 meeting, a decision some board members say violates an agreement that ended a prolonged teacher strike nearly 20 years ago.
Other board members argue the agreement is defunct because it hasnt been recognized in years.
In a 5-4 vote, the board revised a policy to state that bereavement leave will be deducted from the 10 sick days allotted to school employees each year. Employees "experiencing hardship" may appeal to the board for more days off.
Heres how the vote went:
For: Roosevelt Thomas, Clark Bonvillain, Rickie Pitre, Hayes Badeaux and Greg Harding.
Against: L.P. Bordelon, Roger DeHart, Richard Jackson and Don Duplantis.
The previous policy allowed employees two days off when a family member or fellow employee died. All unused sick days roll over into the next school year, allowing them to accrue.
Bonvillain proposed the change because he said bereavement was the only type of leave not deducted from sick days. Employees can take days off for special events such as weddings or graduations as long as they have sick days.
"It just brings everything into line," Bonvillain said in an interview. "They can take days off, but they just have to have the accumulated sick days available."
Pitre said employees made bereavement a "homemade benefit" by using it for more than just immediate family.
The revision "limits the amount of abuse and misuse of the policy," Pitre said. "The boards policies have been too lenient, and there was some abuse going on."
Bonvillain said school system supervisors informed them of the alleged problem.
"I dont want anyone stoned," Bonvillain said at the meeting, "so Im not going to say a word about who I talked to."
Most members agreed on the proposed revision. But they debated over whether it should be sent to the Employee Representative Committee before being passed.
The committee was created in 1990 as part of the Return to Work Agreement, a set of conditions between employees and the board that brought an end to a teacher strike that lasted more than a month.
Comprised of school employees, the committee was tasked with reviewing "additions to policies, regulations and procedures affecting personnel matters and work conditions," the agreement states.
The committee can only make recommendations or advise the board of their opinion, but not scuttle a proposed policy.
Only three board members who served through the strike sit on the board: Rickie Pitre, Clark Bonvillain and Don Duplantis.
"During the strike, one of the contentions was that the board was not listening to its employees," Duplantis told the board. "Yet were doing the same thing again."
Board members who pushed to pass the revision say the employee committee shouldnt influence whether they change a policy.
"I dont think we should make any policy contingent on whatever the blessings of the ERC are," Pitre told the board.
L.P. Bordelon said he favored the revision, but it would be more prudent to allow the employee committee to review it first.
"If we are going to change something, I strongly suggest we go through the ERC," Bordelon told board members. "It takes a little more time to do it and certainly the board can have its way after that."
In an interview, Pitre said the board did not violate policy because the employee committee has long been inactive.
"They probably havent had a legitimate meeting in years," he said. A member of the employee committee who spoke on condition of anonymity for fear of retaliation said the committee plans to meet Thursday to discuss the bereavement policy.
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West Chester Protective Gear is relocating from Monroe to Sharonville's Gateway 75.
- Filed Under
West Chester Protective Gear has outgrown its Monroe facility, and is heading to Sharonville.
The supplier of protective garments, gloves and rainwear will occupy about 260,000 square feet of the Gateway 75 complex, at Kemper and Canal roads, which totals more than 1 million square feet, and is considered the largest available space for distribution, manufacturing and assembly in the Cincinnati area.
The Sharonville facility is 60 percent larger than the company's current location, according to Marketing Communications Manager April D'Angelo. ...


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Looks like Adam Driver is heading to outer… space!
According to a report from Variety, the "Girls" breakout star is nearing a deal to join "Star Wars: Episode VII" as the movie's villain.
The J.J. Abrams continuation of George Lucas' classic franchise is set to start filming in the coming months, and if Driver signs on as the antagonist, he will be the first actor officially cast in the new trilogy.
The report from Variety is mostly light on details, but the write-up does mention that the character Driver will reportedly play is in the vein of Darth Vader, which could honestly mean anything. Will he wear a mask? Or just a lot of black? Will he have a change of heart in the third movie? At this point, all the Darth Vader comparison means is that he'll be a villain in a "Star Wars" movie.
Variety is careful to note that Driver has not officially signed on yet, but that he is close to a deal that would make him the only cast member so far. His name had been mentioned with a bunch of others, including Benedict Cumberbatch and Gary Oldman, who claims to have taken a meeting with Lucasfilm.
The Hollywood Reporter's account of the casting mentioned that insiders believe a lot of the casting on "Episode VII" is already complete and being kept under the tight wraps of non-disclosure agreements. If that's true, Driver's casting would be the first to make it to the outside world.
"Star Wars: Episode VII" is scheduled to open in theaters on December 18, 2015.


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Centaur White Cotton Web 35' Lunge Line With Donut
Centaur White Cotton Web 35' Lunge Line With Donut. This basic piece of schooling equipment should be part of any equestrian's equipment.
The cotton is softer on the hand than nylon, the donut allows for a firm grip, and the 35 foot length allows for large circles.
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Select Local Merchants
Affordable General ServiceRead MoreMaintenance and repair work isn't for everyone. Whether you lack the skills, time, or patience, a quick call to Affordable General Service in Honolulu will surely get the job done. Affordable General Service offers expert landscaping services to keep trees and shrubs looking great. For household issues big and small, give the friendly handymen at Affordable General Service a call.1723 Kamohoalii StreetHonolulu, HI US
Hui Ku Maoli Ola Native Hawaiian Plant SpecialistsRead MoreHui Ku Maoli Ola traces its lineage back to 1999, when friends Rick Barboza and Matt Schirman established the nursery with a mission to preserve and celebrate the distinct flora of the Hawaiian Islands. Today, the company beautifies federal lands, private homes, and retail businesses with more than 100 species of native Hawaiian plants, the descendants of specimens brought from distant shores by ancient Polynesian settlers and very strong wind. The helpful crew tends to rows of waving ferns, shady trees, and flowering bushes as they restore native habitats with professional landscaping or educate students with lectures and field trips.46-403 Haiku RdKaneohe, HI US
Turf and Shrub Care HawaiiRead MoreEasy living requires proactive solutions as problems arise. Call for the handyman services offered by Turf and Shrub Care Hawaii in Kaneohe today. Does your lawn need a little tender loving care? If so, you'd be wise to call upon Turf and Shrub Care Hawaii's great team to get the job done. Turf and Shrub Care Hawaii landscapes even the finickiest of properties. No yard is too tough for their professional team! Next time you need help with repairs around the house, give the friendly handymen at Turf and Shrub Care Hawaii a call.47-875 Ahilama RdKaneohe, HI US
Aloun FarmsRead MoreLoaded with essential vitamins and minerals, the produce from this store will give you the energy your body needs. You'll be happy to know there are amazing parking options in the area.91-1440 Farrington HwyKapolei, HI US
Kua'aina SandwichRead MoreAt Kua'Aina Sandwich, success lies between two halves of a fresh kaiser roll. The shop opened in Hawaii in 1975, and the popularity of its burgers, sandwiches, and fresh cut shoestring fries caused Kua'Aina to expand to a third Oahu location and to franchises in London and Japan. Perhaps people noticed that Kua'Aina's cooks aren't afraid to play around with the traditional burger toppings. Sure, they make classic 1/3- and 1/2- pound cheeseburgers, but they also add accents such as pineapple and avocado. Cheese and avocados make repeat appearances atop Kua'Aina's charbroiled sandwiches. Toasted multi-grain or hearth rye bread serves as the foundation for the tuna-and-avocado sandwich, pastrami sandwich, or a combination BLT-avocado sandwich so delicious that it defies the normal laws of acronyms.Kapolei CommonsKapolei, HI US
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The presence of coconut in southern Panama in pre-Columbian times: clearing up the confusion
Baudouin, Luc
Gunn, Bee F.
Olsen, Kenneth M.
Annals of Botany
The pre-Columbian presence of coconut on the Pacific coast of Panama is attested by a number of independent written accounts. However, recent papers question their accuracy and conclude that coconut was introduced to the region by the Spaniards after their conquests.
In order to examine the value of such claims, an extensive search was conducted of the relevant historical accounts of coconut in America and in the Orient.
Key Results
The Spanish chronicler Oviedo (1478–1557) is found to have effectively used fruit and seed size to distinguish coconut from other palms. In addition, it is shown that he has been inaccurately faulted with incorrectly representing a cluster of coconuts. The original drawing, a cluster of a native Bactris, was in the marginalia and was only assigned to coconut after Oviedo's death. Finally, the location is identified of a coastal Panamanian site described by Pedro Mártir de Anglería and where tidal dispersal of coconuts was observed.
This previously overlooked evidence confirms the pre-historical presence of coconut in Panama. Genetic data indicate that it must have been brought there directly or indirectly from the Philippines. But when, where and by whom remains a subject of research. Further molecular marker studies, computer simulation of natural drift and archaeological research could contribute to this research.
Coconut; Cocos nucifera; New World flora; Panama; oceanic current dissemination; Spanish explorations; Central America; early trans-Pacific voyaging
Related Articles
Stasis and convergence characterize morphological evolution in eupolypod II ferns
Sundue, Michael A.
Rothfels, Carl J.
Annals of Botany
Background and Aims
Patterns of morphological evolution at levels above family rank remain underexplored in the ferns. The present study seeks to address this gap through analysis of 79 morphological characters for 81 taxa, including representatives of all ten families of eupolypod II ferns. Recent molecular phylogenetic studies demonstrate that the evolution of the large eupolypod II clade (which includes nearly one-third of extant fern species) features unexpected patterns. The traditional 'athyrioid' ferns are scattered across the phylogeny despite their apparent morphological cohesiveness, and mixed among these seemingly conservative taxa are morphologically dissimilar groups that lack any obvious features uniting them with their relatives. Maximum-likelihood and maximum-parsimony character optimizations are used to determine characters that unite the seemingly disparate groups, and to test whether the polyphyly of the traditional athyrioid ferns is due to evolutionary stasis (symplesiomorphy) or convergent evolution. The major events in eupolypod II character evolution are reviewed, and character and character state concepts are reappraised, as a basis for further inquiries into fern morphology.
Characters were scored from the literature, live plants and herbarium specimens, and optimized using maximum-parsimony and maximum-likelihood, onto a highly supported topology derived from maximum-likelihood and Bayesian analysis of molecular data. Phylogenetic signal of characters were tested for using randomization methods and fitdiscrete.
Key Results
The majority of character state changes within the eupolypod II phylogeny occur at the family level or above. Relative branch lengths for the morphological data resemble those from molecular data and fit an ancient rapid radiation model (long branches subtended by very short backbone internodes), with few characters uniting the morphologically disparate clades. The traditional athyrioid ferns were circumscribed based upon a combination of symplesiomorphic and homoplastic characters. Petiole vasculature consisting of two bundles is ancestral for eupolypods II and a synapomorphy for eupolypods II under deltran optimization. Sori restricted to one side of the vein defines the recently recognized clade comprising Rhachidosoraceae through Aspleniaceae, and sori present on both sides of the vein is a synapomorphy for the Athyriaceae sensu stricto. The results indicate that a chromosome base number of x =41 is synapomorphic for all eupolypods, a clade that includes over two-thirds of extant fern species.
The integrated approach synthesizes morphological studies with current phylogenetic hypotheses and provides explicit statements of character evolution in the eupolypod II fern families. Strong character support is found for previously recognized clades, whereas few characters support previously unrecognized clades. Sorus position appears to be less complicated than previously hypothesized, and linear sori restricted to one side of the vein support the clade comprising Aspleniaceae, Diplaziopsidaceae, Hemidictyaceae and Rachidosoraceae – a lineage only recently identified. Despite x =41 being a frequent number among extant species, to our knowledge it has not previously been demonstrated as the ancestral state. This is the first synapomorphy proposed for the eupolypod clade, a lineage comprising 67 % of extant fern species. This study provides some of the first hypotheses of character evolution at the family level and above in light of recent phylogenetic results, and promotes further study in an area that remains open for original observation.
Athyriaceae; character state reconstruction; convergent evolution; Diplaziopsidaceae; eupolypods II; morphological evolution; Polypodiales; rate of evolution; Rhachidosoraceae; symplesiomorphy; Woodsiaceae
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An underground tale: contribution of microbial activity to plant iron acquisition via ecological processes
Jin, Chong Wei
Ye, Yi Quan
Zheng, Shao Jian
Annals of Botany
Iron (Fe) deficiency in crops is a worldwide agricultural problem. Plants have evolved several strategies to enhance Fe acquisition, but increasing evidence has shown that the intrinsic plant-based strategies alone are insufficient to avoid Fe deficiency in Fe-limited soils. Soil micro-organisms also play a critical role in plant Fe acquisition; however, the mechanisms behind their promotion of Fe acquisition remain largely unknown.
This review focuses on the possible mechanisms underlying the promotion of plant Fe acquisition by soil micro-organisms.
Fe-deficiency-induced root exudates alter the microbial community in the rhizosphere by modifying the physicochemical properties of soil, and/or by their antimicrobial and/or growth-promoting effects. The altered microbial community may in turn benefit plant Fe acquisition via production of siderophores and protons, both of which improve Fe bioavailability in soil, and via hormone generation that triggers the enhancement of Fe uptake capacity in plants. In addition, symbiotic interactions between micro-organisms and host plants could also enhance plant Fe acquisition, possibly including: rhizobium nodulation enhancing plant Fe uptake capacity and mycorrhizal fungal infection enhancing root length and the nutrient acquisition area of the root system, as well as increasing the production of Fe3+ chelators and protons.
Hormones; iron deficiency; microbial community structure; siderophore; symbiosis
Related Articles
Campanulaceae: a family with small seeds that require light for germination
Koutsovoulou, Katerina
Daws, Matthew I.
Thanos, Costas A.
Annals of Botany
Background and Aims
The Campanulaceae is a large cosmopolitan family, but is understudied in terms of germination, and seed biology in general. Small seed mass (usually in the range 10–200 µg) is a noteworthy trait of the family, and having small seeds is commonly associated with a light requirement. Thus, the purpose of this study was to investigate the effect of light on germination in 131 taxa of the Campanulaceae family, from all five continents of its distribution.
For all taxa, seed germination was tested in light (8 or 12 h photoperiod) and continuous darkness under constant and alternating temperatures. For four taxa, the effect of light on germination was examined over a wide range of temperatures on a thermogradient plate, and the possible substitution of the light requirement by gibberellic acid and nitrate was examined in ten taxa.
Key Results
For all 131 taxa, seed germination was higher in light than in darkness for every temperature tested. Across species, the light requirement decreased significantly with increasing seed mass. For larger seeded species, germination in the dark reached higher levels under alternating than under constant temperatures. Gibberellic acid promoted germination in darkness whereas nitrates partially substituted for a light requirement only in species showing some dark germination.
A light requirement for germination, observed in virtually all taxa examined, constitutes a collective characteristic of the family. It is postulated that smaller seeded taxa might germinate only on the soil surface or at shallow depths, while larger seeded species might additionally germinate when buried in the soil if cued to do so by fluctuating temperatures.
Campanulaceae; germination; light requirement; seed mass; constant vs. alternating temperatures; gibberellic acid; nitrate
Related Articles
Plant development controls leaf area expansion in alfalfa plants competing for light
Baldissera, Tiago Celso
Frak, Ela
Carvalho, Paulo Cesar de Faccio
Louarn, Gaëtan
Annals of Botany
Background and Aims
The growth of crops in a mixture is more variable and difficult to predict than that in pure stands. Light partitioning and crop leaf area expansion play prominent roles in explaining this variability. However, in many crops commonly grown in mixtures, including the forage species alfalfa, the sensitivity and relative importance of the physiological responses involved in the light modulation of leaf area expansion are still to be established. This study was designed to assess the relative sensitivity of primary shoot development, branching and individual leaf expansion in alfalfa in response to light availability.
Two experiments were carried out. The first studied isolated plants to assess the potential development of different shoot types and growth periods. The second consisted of manipulating the intensity of competition for light using a range of canopies in pure and mixed stands at two densities so as to evaluate the relative effects on shoot development, leaf growth, and plant and shoot demography.
Key Results
Shoot development in the absence of light competition was deterministic (constant phyllochrons of 32·5 °Cd and 48·2 °Cd for primary axes and branches, branching probability of 1, constant delay of 1·75 phyllochron before axillary bud burst) and identical irrespective of shoot type and growth/regrowth periods. During light competition experiments, changes in plant development explained most of the plant leaf area variations, with average leaf size contributing to a lesser extent. Branch development and the number of shoots per plant were the leaf area components most affected by light availability. Primary axis development and plant demography were only affected in situations of severe light competition.
Plant leaf area components differed with regard to their sensitivity to light competition. The potential shoot development model presented in this study could serve as a framework to integrate light responses in alfalfa crop models.
Medicago sativa; leaf area; light competition; branching; shoot; development; leaf growth; morphogenesis; model
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Autotetraploids of Vicia cracca show a higher allelic richness in natural populations and a higher seed set after artificial selfing than diploids
Eliášová, Anežka
Trávníček, Pavel
Mandák, Bohumil
Münzbergová, Zuzana
Annals of Botany
Background and Aims
Despite the great importance of autopolyploidy in the evolution of angiosperms, relatively little attention has been devoted to autopolyploids in natural polyploid systems. Several hypotheses have been proposed to explain why autopolyploids are so common and successful, for example increased genetic diversity and heterozygosity and the transition towards selfing. However, case studies on patterns of genetic diversity and on mating systems in autopolyploids are scarce. In this study allozymes were employed to investigate the origin, population genetic diversity and mating system in the contact zone between diploid and assumed autotetraploid cytotypes of Vicia cracca in Central Europe.
Four enzyme systems resolved in six putative loci were investigated in ten diploid, ten tetraploid and five mixed-ploidy populations. Genetic diversity and heterozygosity, partitioning of genetic diversity among populations and cytotypes, spatial genetic structure and fixed heterozygosity were analysed. These studies were supplemented by a pollination experiment and meiotic chromosome observation.
Key Results and Conclusions
Weak evidence of fixed heterozygosity, a low proportion of unique alleles and genetic variation between cytotypes similar to the variation among populations within cytotypes supported the autopolyploid origin of tetraploids, although no multivalent formation was observed. Tetraploids possessed more alleles than diploids and showed higher observed zygotic heterozygosity than diploids, but the observed gametic heterozygosity was similar to the value observed in diploids and smaller than expected under panmixis. Values of the inbreeding coefficient and differentiation among populations (ρST) suggested that the breeding system in both cytotypes of V. cracca is mixed mating with prevailing outcrossing. The reduction in seed production of tetraploids after selfing was less than that in diploids. An absence of correlation between genetic and geographic distances and high differentiation among neighbouring tetraploid populations supports the secondary contact hypothesis with tetraploids of several independent origins in Central Europe. Nevertheless, the possibility of a recent in situ origin of tetraploids through a triploid bridge in some regions is also discussed.
Autopolyploidy; allozymes; genetic diversity; heterozygosity; fixed heterozygosity; genetic differentiation; F-statistics; inbreeding depression; mating system; artificial pollination; meiotic chromosomes; Vicia cracca
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Genetic and palaeo-climatic evidence for widespread persistence of the coastal tree species Eucalyptus gomphocephala (Myrtaceae) during the Last Glacial Maximum
Nevill, Paul G.
Bradbury, Donna
Williams, Anna
Tomlinson, Sean
Krauss, Siegfried L.
Annals of Botany
Background and Aims
Few phylogeographic studies have been undertaken of species confined to narrow, linear coastal systems where past sea level and geomorphological changes may have had a profound effect on species population sizes and distributions. In this study, a phylogeographic analysis was conducted of Eucalyptus gomphocephala (tuart), a tree species restricted to a 400 × 10 km band of coastal sand-plain in south west Australia. Here, there is little known about the response of coastal vegetation to glacial/interglacial climate change, and a test was made as to whether this species was likely to have persisted widely through the Last Glacial Maximum (LGM), or conforms to a post-LGM dispersal model of recovery from few refugia.
The genetic structure over the entire range of tuart was assessed using seven nuclear (21 populations; n = 595) and four chloroplast (24 populations; n = 238) microsatellite markers designed for eucalypt species. Correlative palaeodistribution modelling was also conducted based on five climatic variables, within two LGM models.
Key Results
The chloroplast markers generated six haplotypes, which were strongly geographically structured (GST = 0·86 and RST = 0·75). Nuclear microsatellite diversity was high (overall mean HE 0·75) and uniformly distributed (FST = 0·05), with a strong pattern of isolation by distance (r2 = 0·362, P = 0·001). Distribution models of E. gomphocephala during the LGM showed a wide distribution that extended at least 30 km westward from the current distribution to the palaeo-coastline.
The chloroplast and nuclear data suggest wide persistence of E. gomphocephala during the LGM. Palaeodistribution modelling supports the conclusions drawn from genetic data and indicates a widespread westward shift of E. gomphocephala onto the exposed continental shelf during the LGM. This study highlights the importance of the inclusion of complementary, non-genetic data (information on geomorphology and palaeoclimate) to interpret phylogeographic patterns.
Australian biogeography; climate change; coastal geomorphology; Eucalyptus gomphocephala; founder effects; Last Glacial Maximum; LGM; microsatellites; Myrtaceae; palaeodistribution modelling; phylogeography; southern hemisphere; south-western Australia; tuart
Related Articles
Feeding on prey increases photosynthetic efficiency in the carnivorous sundew Drosera capensis
Pavlovič, Andrej
Krausko, Miroslav
Libiaková, Michaela
Adamec, Lubomír
Annals of Botany
Backround and Aims
It has been suggested that the rate of net photosynthesis (AN) of carnivorous plants increases in response to prey capture and nutrient uptake; however, data confirming the benefit from carnivory in terms of increased AN are scarce and unclear. The principal aim of our study was to investigate the photosynthetic benefit from prey capture in the carnivorous sundew Drosera capensis.
Prey attraction experiments were performed, with measurements and visualization of enzyme activities, elemental analysis and pigment quantification together with simultaneous measurements of gas exchange and chlorophyll a fluorescence in D. capensis in response to feeding with fruit flies (Drosophila melanogaster).
Key Results
Red coloration of tentacles did not act as a signal to attract fruit flies onto the traps. Phosphatase, phophodiesterase and protease activities were induced 24 h after prey capture. These activities are consistent with the depletion of phosphorus and nitrogen from digested prey and a significant increase in their content in leaf tissue after 10 weeks. Mechanical stimulation of tentacle glands alone was not sufficient to induce proteolytic activity. Activities of β-D-glucosidases and N-acetyl-β-D-glucosaminidases in the tentacle mucilage were not detected. The uptake of phosphorus from prey was more efficient than that of nitrogen and caused the foliar N:P ratio to decrease; the contents of other elements (K, Ca, Mg) decreased slightly in fed plants. Increased foliar N and P contents resulted in a significant increase in the aboveground plant biomass, the number of leaves and chlorophyll content as well as AN, maximum quantum yield (Fv/Fm) and effective photochemical quantum yield of photosystem II (ΦPSII).
According to the stoichiometric relationships among different nutrients, the growth of unfed D. capensis plants was P-limited. This P-limitation was markedly alleviated by feeding on fruit flies and resulted in improved plant nutrient status and photosynthetic performance. This study supports the original cost/benefit model proposed by T. Givnish almost 30 years ago and underlines the importance of plant carnivory for increasing phosphorus, and thereby photosynthesis.
Carnivorous plant; cost/benefit; Drosera capensis; cape sundew; fruit flies; digestive enzymes; nitrogen; phosphorus; photosynthesis; sundew
Related Articles
Molecular and quantitative trait variation within and among small fragmented populations of the endangered plant species Psilopeganum sinense
Ye, Qigang
Tang, Feiyan
Wei, Na
Yao, Xiaohong
Annals of Botany
Background and Aims
Natural selection and genetic drift are important evolutionary forces in determining genetic and phenotypic differentiation in plant populations. The extent to which these two distinct evolutionary forces affect locally adaptive quantitative traits has been well studied in common plant and animal species. However, we know less about how quantitative traits respond to selection pressures and drift in endangered species that have small population sizes and fragmented distributions. To address this question, this study assessed the relative strengths of selection and genetic drift in shaping population differentiation of phenotypic traits in Psilopeganum sinense, a naturally rare and recently endangered plant species.
Population differentiation at five quantitative traits (QST) obtained from a common garden experiment was compared with differentiation at putatively neutral microsatellite markers (FST) in seven populations of P. sinense. QST estimates were derived using a Bayesian hierarchical variance component method.
Key Results
Trait-specific QST values were equal to or lower than FST. Neutral genetic diversity was not correlated with quantitative genetic variation within the populations of P. sinense.
Despite the prevalent empirical evidence for QST > FST, the results instead suggest a definitive role of stabilizing selection and drift leading to phenotypic differentiation among small populations. Three traits exhibited a significantly lower QST relative to FST, suggesting that populations of P. sinense might have experienced stabilizing selection for the same optimal phenotypes despite large geographical distances between populations and habitat fragmentation. For the other two traits, QST estimates were of the same magnitude as FST, indicating that divergence in these traits could have been achieved by genetic drift alone. The lack of correlation between molecular marker and quantitative genetic variation suggests that sophisticated considerations are required for the inference of conservation measures of P. sinense from neutral genetic markers.
Psilopeganum sinense; Chinese privet; stabilizing selection; genetic drift; quantitative traits; QST; neutral microsatellite markers; FST; local adaptation, habitat fragmentation
Related Articles
Dormancy cycling and persistence of seeds in soil of a cold desert halophyte shrub
Cao, Dechang
Baskin, Carol C.
Baskin, Jerry M.
Yang, Fan
Huang, Zhenying
Annals of Botany
Background and Aims
Formation of seed banks and dormancy cycling are well known in annual species, but not in woody species. In this study it was hypothesized that the long-lived halophytic cold desert shrub Kalidium gracile has a seed bank and dormancy cycling, which help restrict germination to a favourable time for seedling survival.
Fresh seeds were buried in November 2009 and exhumed and tested for germination monthly from May 2010 to December 2011 over a range of temperatures and salinities. Germination recovery and viability were determined after exposure to salinity and water stress. Seedling emergence and dynamics of the soil seed bank were investigated in the field.
Key Results
Seeds of K. gracile had a soil seed bank of 7030 seeds m−2 at the beginning of the growing season. About 72 % of the seeds were depleted from the soil seed bank during a growing season, and only 1·4 % of them gave rise to seedlings that germinated early enough to reach a stage of growth at which they could survive to overwinter. About 28 % of the seeds became part of a persistent soil seed bank. Buried seeds exhibited an annual non-dormancy/conditional dormancy (ND/CD) cycle, and germination varied in sensitivity to salinity during the cycle. Dormancy cycling is coordinated with seasonal environmental conditions in such a way that the seeds germinate in summer, when there is sufficient precipitation for seedling establishment.
Kalidium gracile has three life history traits that help ensure persistence at a site: a polycarpic perennial life cycle, a persistent seed bank and dormancy cycling. The annual ND/CD cycle in seeds of K. gracile contributes to seedling establishment of this species in the unpredictable desert environment and to maintenance of a persistent soil seed bank. This is the first report of a seed dormancy cycle in a cold desert shrub.
Cold desert habitat; dormancy cycling; halophyte; Kalidium gracile; salt tolerance; seed germination; seedling recruitment; soil seed bank
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Flow cytometric analysis of pollen grains collected from individual bees provides information about pollen load composition and foraging behaviour
Kron, Paul
Kwok, Allison
Husband, Brian C.
Annals of Botany
Background and Aims
Understanding the species composition of pollen on pollinators has applications in agriculture, conservation and evolutionary biology. Current identification methods, including morphological analysis, cannot always discriminate taxa at the species level. Recent advances in flow cytometry techniques for pollen grains allow rapid testing of large numbers of pollen grains for DNA content, potentially providing improved species resolution.
A test was made as to whether pollen loads from single bees (honey-bees and bumble-bees) could be classified into types based on DNA content, and whether good estimates of proportions of different types could be made. An examination was also made of how readily DNA content can be used to identify specific pollen species.
Key Results
The method allowed DNA contents to be quickly found for between 250 and 9391 pollen grains (750–28 173 nuclei) from individual honey-bees and between 81 and 11 512 pollen grains (243–34 537 nuclei) for bumble-bees. It was possible to identify a minimum number of pollen species on each bee and to assign proportions of each pollen type (based on DNA content) present.
The information provided by this technique is promising but is affected by the complexity of the pollination environment (i.e. number of flowering species present and extent of overlap in DNA content). Nevertheless, it provides a new tool for examining pollinator behaviour and between-species or cytotype pollen transfer, particularly when used in combination with other morphological, chemical or genetic techniques.
Flow cytometry; pollen; Apis mellifera; Bombus; pollen load composition; DNA content; bumble-bee; honey-bee; foraging behaviour; pollination
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Regulation of root morphogenesis in arbuscular mycorrhizae: what role do fungal exudates, phosphate, sugars and hormones play in lateral root formation?
Fusconi, Anna
Annals of Botany
Arbuscular mycorrhizae (AMs) form a widespread root–fungus symbiosis that improves plant phosphate (Pi) acquisition and modifies the physiology and development of host plants. Increased branching is recognized as a general feature of AM roots, and has been interpreted as a means of increasing suitable sites for colonization. Fungal exudates, which are involved in the dialogue between AM fungi and their host during the pre-colonization phase, play a well-documented role in lateral root (LR) formation. In addition, the increased Pi content of AM plants, in relation to Pi-starved controls, as well as changes in the delivery of carbohydrates to the roots and modulation of phytohormone concentration, transport and sensitivity, are probably involved in increasing root system branching.
This review discusses the possible causes of increased branching in AM plants. The differential root responses to Pi, sugars and hormones of potential AM host species are also highlighted and discussed in comparison with those of the non-host Arabidopsis thaliana.
Fungal exudates are probably the main compounds regulating AM root morphogenesis during the first colonization steps, while a complex network of interactions governs root development in established AMs. Colonization and high Pi act synergistically to increase root branching, and sugar transport towards the arbusculated cells may contribute to LR formation. In addition, AM colonization and high Pi generally increase auxin and cytokinin and decrease ethylene and strigolactone levels. With the exception of cytokinins, which seem to regulate mainly the root:shoot biomass ratio, these hormones play a leading role in governing root morphogenesis, with strigolactones and ethylene blocking LR formation in the non-colonized, Pi-starved plants, and auxin inducing them in colonized plants, or in plants grown under high Pi conditions.
Arbuscular mycorrhizae; root branching; lateral roots; fungal exudates; phosphate; sugars; auxin; cytokinins; ethylene; strigolactones; Arabidopsis thaliana
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Root cortical aerenchyma inhibits radial nutrient transport in maize (Zea mays)
Hu, Bo
Henry, Amelia
Brown, Kathleen M.
Lynch, Jonathan P.
Annals of Botany
Background and Aims
Formation of root cortical aerenchyma (RCA) can be induced by nutrient deficiency. In species adapted to aerobic soil conditions, this response is adaptive by reducing root maintenance requirements, thereby permitting greater soil exploration. One trade-off of RCA formation may be reduced radial transport of nutrients due to reduction in living cortical tissue. To test this hypothesis, radial nutrient transport in intact roots of maize (Zea mays) was investigated in two radiolabelling experiments employing genotypes with contrasting RCA.
In the first experiment, time-course dynamics of phosphate loading into the xylem were measured from excised nodal roots that varied in RCA formation. In the second experiment, uptake of phosphate, calcium and sulphate was measured in seminal roots of intact young plants in which variation in RCA was induced by treatments altering ethylene action or genetic differences.
Key Results
In each of three paired genotype comparisons, the rate of phosphate exudation of high-RCA genotypes was significantly less than that of low-RCA genotypes. In the second experiment, radial nutrient transport of phosphate and calcium was negatively correlated with the extent of RCA for some genotypes.
The results support the hypothesis that RCA can reduce radial transport of some nutrients in some genotypes, which could be an important trade-off of this trait.
Aerenchyma; radial transport; root; nutrient uptake; phosphorus; sulfur; calcium; maize; Zea mays
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Peroxynitrite (ONOO−) is endogenously produced in arabidopsis peroxisomes and is overproduced under cadmium stress
Corpas, Francisco J.
Barroso, Juan B.
Annals of Botany
Background and Aims
Peroxisomes are subcellular compartments involved in multiple cellular metabolic pathways. Peroxynitrite (ONOO−) is a nitric oxide-derived molecule which is a nitrating species that causes nitration of proteins. This study used cell biology techniques to explore the potential presence of peroxynitrite in peroxisomes and evaluated its content under stress conditions (excess cadmium).
Peroxynitrite, nitric oxide and superoxide anion were studied using cell-permeable specific fluorescent probes by confocal laser scanning microscopy in Arabidopsis thaliana transgenic plants expressing cyan fluorescent protein through the addition of peroxisomal targeting signal 1 (PTS1), which enables peroxisomes to be visualized in vivo.
Key Results
When no stress was applied, peroxynitrite was clearly localized in the peroxisomes of roots and stomatal guard cells. Under cadmium (150 μm) stress, the generation of peroxynitrite, nitric oxide and the superoxide anion (O2·–) increased and was localized in peroxisomes and the cytosol, participating in the generation of nitro-oxidative stress.
The results show that peroxisomes are an endogenous source of peroxynitrite, which is over-produced under cadmium stress, suggesting that the metabolism of reactive nitrogen species in peroxisomes could participate in the mechanism of the response to this heavy metal.
Nitric oxide; peroxisomes; peroxynitrite; protein tyrosine nitration; cadmium; heavy metal; nitrosative stress; Arabidopsis thaliana
Related Articles
In the right place at the right time: Parnassia resolves the herkogamy dilemma by accurate repositioning of stamens and stigmas
Armbruster, W. Scott
Corbet, Sarah A.
Vey, Aidan J. M.
Liu, Shu-Juan
Huang, Shuang-Quan
Annals of Botany
Background and Aims
Spatial (herkogamy) and temporal (dichogamy) separation of pollen presentation and stigma receptivity have been interpreted as reducing interference between male and female functions in hermaphroditic flowers. However, spatial separation leads to a potential conflict: reduced pollination accuracy, where pollen may be placed in a location on the pollinator different from the point of stigma contact.
To understand better how herkogamous flowers resolve this conflict, a study was made of a subalpine herb, Parnassia epunctulata, the nectariferous flowers of which exhibit sequential anther dehiscence (staggered pollen presentation) and stamen movements; usually one newly dehisced anther is positioned each day over the central gynoecium, while the older stamens bend away from the central position.
Key Results
The open flowers were visited by a variety of pollinators, most of which were flies. Seed set was pollinator-dependent (bagged flowers set almost no seeds) and pollen-limited (manual pollination increased seed set over open pollination). Analyses of adaptive accuracy showed that coordinated stamen movements and style elongation (movement herkogamy) dramatically increased pollination accuracy. Specifically, dehiscing anthers and receptive stigmas were positioned accurately in the vertical and horizontal planes in relation to the opposite sexual structure and pollinator position. By contrast, the spatial correspondence between anthers and stigma was dramatically lower before the anthers dehisced and after stamens bent outwards, as well as before and after the period of stigmatic receptivity.
It is shown for the first time that a combination of movement herkogamy and dichogamy can maintain high pollination accuracy in flowers with generalized pollination. Staggered pollen and stigma presentation with spatial correspondence can both reduce sexual interference and improve pollination accuracy.
Adaptive accuracy; Celastraceae; dichogamy; generalist pollination; herkogamy; mating system; Parnassia epunctulata; Parnassiaceae; staggered pollen presentation; sexual interference; stamen movement
Related Articles
Ontogenetic tissue modification in Malus fruit peduncles: the role of sclereids
Horbens, Melanie
Feldner, Alexander
Höfer, Monika
Neinhuis, Christoph
Annals of Botany
Background and Aims
Apple (Malus) fruit peduncles are highly modified stems with limited secondary growth because fruit ripening lasts only one season. They must reliably connect rather heavy fruits to the branch and cope with increasing fruit weight, which induces dynamic stresses under oscillating wind loads. This study focuses on tissue modification of these small, exposed structures during fruit development.
A combination of microscopic, static and dynamic mechanical tests, as well as Raman spectroscopy, was used to study structure–function relationships in peduncles of one cultivar and 12 wild species, representatively chosen from all sections of the genus Malus. Tissue differentiation and ontogenetic changes in mechanical properties of Malus peduncles were observed throughout one growing season and after successive removal of tissues.
Key Results
Unlike in regular stems, the vascular cambium produces mainly phloem during secondary growth. Hence, in addition to a reduced xylem, all species developed a centrally arranged sclerenchyma ring composed of fibres and brachysclereids. Based on differences in cell-wall thickness, and proportions and arrangement of sclereids, two types of peduncle construction could be distinguished. Fibres provide an increased maximum tensile strength and contribute most to the overall axial rigidity of the peduncles. Sclereids contribute insignificantly to peduncle strength; however, despite being shown to have a lower elastic modulus than fibres, they are the most effective tissue in stiffening peduncles against bending.
The experimental data revealed that sclereids originating from cortical parenchyma act as 'accessory' cells to enhance proportions of sclerenchyma during secondary growth in peduncles. The mechanism can be interpreted as an adaptation to continuously increasing fruit loads. Under oscillating longitudinal stresses, sclereids may be regarded as regulating elements between maintenance of stiffness and viscous damping, the latter property being attributed to the cortical parenchyma.
Apple; biomechanics; fibres; fruit peduncle; fruit load; functional anatomy; Malus; sclereids; viscous damping
Related Articles
Resolving ancient radiations: can complete plastid gene sets elucidate deep relationships among the tropical gingers (Zingiberales)?
Barrett, Craig F.
Specht, Chelsea D.
Leebens-Mack, Jim
Stevenson, Dennis Wm.
Zomlefer, Wendy B.
Davis, Jerrold I.
Annals of Botany
Background and Aims
Zingiberales comprise a clade of eight tropical monocot families including approx. 2500 species and are hypothesized to have undergone an ancient, rapid radiation during the Cretaceous. Zingiberales display substantial variation in floral morphology, and several members are ecologically and economically important. Deep phylogenetic relationships among primary lineages of Zingiberales have proved difficult to resolve in previous studies, representing a key region of uncertainty in the monocot tree of life.
Next-generation sequencing was used to construct complete plastid gene sets for nine taxa of Zingiberales, which were added to five previously sequenced sets in an attempt to resolve deep relationships among families in the order. Variation in taxon sampling, process partition inclusion and partition model parameters were examined to assess their effects on topology and support.
Key Results
Codon-based likelihood analysis identified a strongly supported clade of ((Cannaceae, Marantaceae), (Costaceae, Zingiberaceae)), sister to (Musaceae, (Lowiaceae, Strelitziaceae)), collectively sister to Heliconiaceae. However, the deepest divergences in this phylogenetic analysis comprised short branches with weak support. Additionally, manipulation of matrices resulted in differing deep topologies in an unpredictable fashion. Alternative topology testing allowed statistical rejection of some of the topologies. Saturation fails to explain observed topological uncertainty and low support at the base of Zingiberales. Evidence for conflict among the plastid data was based on a support metric that accounts for conflicting resampled topologies.
Many relationships were resolved with robust support, but the paucity of character information supporting the deepest nodes and the existence of conflict suggest that plastid coding regions are insufficient to resolve and support the earliest divergences among families of Zingiberales. Whole plastomes will continue to be highly useful in plant phylogenetics, but the current study adds to a growing body of literature suggesting that they may not provide enough character information for resolving ancient, rapid radiations.
Tropical gingers; Zingiberales; plastome; next-generation sequencing; Illumina; phylogeny; evolution; monocots; support; phylogenomics; ancient radiation; plastid gene set
Related Articles
Plant Cuttings
Chaffey, Nigel
Annals of Botany
Related Articles
Evolution of pollination niches and floral divergence in the generalist plant Erysimum mediohispanicum
Gómez, J. M.
Muñoz-Pajares, A. J.
Abdelaziz, M.
Lorite, J.
Perfectti, F.
Annals of Botany
Background and Aims
How generalist plants diverge in response to pollinator selection without becoming specialized is still unknown. This study explores this question, focusing on the evolution of the pollination system in the pollination generalist Erysimum mediohispanicum (Brassicaceae).
Pollinator assemblages were surveyed from 2001 to 2010 in 48 geo-referenced populations covering the entire geographic distribution of E. mediohispanicum. Bipartite modularity, a complex network tool, was used to find the pollination niche of each population. Evolution of the pollination niches and the correlated evolution of floral traits and pollination niches were explored using within-species comparative analyses.
Key Results
Despite being generalists, the E. mediohispanicum populations studied can be classified into five pollination niches. The boundaries between niches were not sharp, the niches differing among them in the relative frequencies of the floral visitor functional groups. The absence of spatial autocorrelation and phylogenetic signal indicates that the niches were distributed in a phylogeographic mosaic. The ancestral E. mediohispanicum populations presumably belonged to the niche defined by a high number of beetle and ant visits. A correlated evolution was found between pollination niches and some floral traits, suggesting the existence of generalist pollination ecotypes.
It is conjectured that the geographic variation in pollination niches has contributed to the observed floral divergence in E. mediohispanicum. The process mediating this floral divergence presumably has been adaptive wandering, but the adaptation to the local pollinator faunas has been not universal. The outcome is a landscape where a few populations locally adapted to their pollination environment (generalist pollination ecotypes) coexist with many populations where this local adaptation has failed and where the plant phenotype is not primarily shaped by pollinators.
Adaptive wandering; generalist pollination ecotype; pollination niches; floral divergence; Erysimum mediohispanicum; Brassicaceae; speciation
Related Articles
Do specialized flowers promote reproductive isolation? Realized pollination accuracy of three sympatric Pedicularis species
Armbruster, W. Scott
Shi, Xiao-Qing
Huang, Shuang-Quan
Annals of Botany
Background and Aims
Interest in pollinator-mediated evolutionary divergence of flower phenotype and speciation in plants has been at the core of plant evolutionary studies since Darwin. Specialized pollination is predicted to lead to reproductive isolation and promote speciation among sympatric species by promoting partitioning of (1) the species of pollinators used, (2) when pollinators are used, or (3) the sites of pollen placement. Here this last mechanism is investigated by observing the pollination accuracy of sympatric Pedicularis species (Orobanchacae).
Pollinator behaviour was observed on three species of Pedicularis (P. densispica, P. tricolor and P. dichotoma) in the Hengduan Mountains, south-west China. Using fluorescent powder and dyed pollen, the accuracy was assessed of stigma contact with, and pollen deposition on, pollinating bumble-bees, respectively.
Key Results
All three species of Pedicularis were pollinated by bumble-bees. It was found that the adaptive accuracy of female function was much higher than that of male function in all three flower species. Although peak pollen deposition corresponded to the optimal location on the pollinator (i.e. the site of stigma contact) for each species, substantial amounts of pollen were scattered over much of the bees' bodies.
The Pedicularis species studied in the eastern Himalayan region did not conform with Grant's 'Pedicularis Model' of mechanical reproductive isolation. The specialized flowers of this diverse group of plants seem unlikely to have increased the potential for reproductive isolation or influenced rates of speciation. It is suggested instead that the extreme species richness of the Pedicularis clade was generated in other ways and that specialized flowers and substantial pollination accuracy evolved as a response to selection generated by the diversity of co-occurring congeners.
Adaptive accuracy; Bombus; evolution; floral precision; Pedicularis densispica; P. tricolor; P. dichotoma; pollination; reproductive isolation; specialization; speciation
Related Articles
Floral polymorphism and the fitness implications of attracting pollinating and florivorous insects
de Jager, Marinus L.
Ellis, Allan G.
Annals of Botany
Background and Aims
Floral polymorphism is frequently attributed to pollinator-mediated selection. Multiple studies, however, have revealed the importance of non-pollinating visitors in floral evolution. Using the polymorphic annual daisy Ursinia calenduliflora, this study investigated the importance of different insect visitors, and their effects on fitness, in the maintenance of floral polymorphism.
The spatial structure of a discrete floral polymorphism was characterized based on the presence/absence of anthocyanin floret spots in U. calenduliflora. A 3-year observational study was then conducted in polymorphic populations to investigate differences in visitation rates of dominant visitors to floral morphs. Experiments were performed to explore the floral preference of male and female Megapalpus capensis (the dominant insect visitor) and their effectiveness as pollinators. Next, floral damage by antagonistic florivores and the reproductive success of the two floral morphs were surveyed in multiple populations and years.
Key Results
Floral polymorphism in U. calenduliflora was structured spatially, as were insect visitation patterns. Megapalpus capensis males were the dominant visitors and exhibited strong preference for the spotted morph in natural and experimental observations. While this may indicate potential fitness benefits for the spotted morph, female fitness did not differ between floral morphs. However, as M. capensis males are very efficient at exporting U. calenduliflora pollen, their preference may likely increase the reproductive fitness of the spotted morph through male fitness components. The spotted morph, however, also suffered significantly greater costs due to ovule predation by florivores than the spotless morph.
The results suggest that pollinators and florivores may potentially exert antagonistic selection that could contribute to the maintenance of floral polymorphism across the range of U. calenduliflora. The relative strength of selection imposed by each agent is potentially determined by insect community composition and abundance at each site, highlighting the importance of community context in the evolution of floral phenotypes.
Antagonistic selection; bee flies; community context; floral polymorphism; florivory; monkey beetles; ovule predation; pollen export; pollinator-mediated selection; Ursinia calenduliflora; Megapalpus capensis
Related Articles
Do pollinator distributions underlie the evolution of pollination ecotypes in the Cape shrub Erica plukenetii?
Van der Niet, Timotheüs
Pirie, Michael D.
Shuttleworth, Adam
Johnson, Steven D.
Midgley, Jeremy J.
Annals of Botany
Background and Aims
According to the Grant–Stebbins model of pollinator-driven divergence, plants that disperse beyond the range of their specialized pollinator may adapt to a new pollination system. Although this model provides a compelling explanation for pollination ecotype formation, few studies have directly tested its validity in nature. Here we investigate the distribution and pollination biology of several subspecies of the shrub Erica plukenetii from the Cape Floristic Region in South Africa. We analyse these data in a phylogenetic context and combine these results with information on pollinator ranges to test whether the evolution of pollination ecotypes is consistent with the Grant–Stebbins model.
Methods and Key Results
Pollinator observations showed that the most common form of E. plukenetii with intermediate corolla length is pollinated by short-billed Orange-breasted sunbirds. Populations at the northern fringe of the distribution are characterized by long corollas, and are mainly pollinated by long-billed Malachite sunbirds. A population with short corollas in the centre of the range was mainly pollinated by insects, particularly short-tongued noctuid moths. Bird exclusion in this population did not have an effect on fruit set, while insect exclusion reduced fruit set. An analysis of floral scent across the range, using coupled gas chromatography–mass spectrometry, showed that the scent bouquets of flowers from moth-pollinated populations are characterized by a larger number of scent compounds and higher emission rates than those in bird-pollinated populations. This was also reflected in clear separation of moth- and bird-pollinated populations in a two-dimensional phenotype space based on non-metric multidimensional scaling analysis of scent data. Phylogenetic analyses of chloroplast and nuclear DNA sequences strongly supported monophyly of E. plukenetii, but not of all the subspecies. Reconstruction of ancestral character states suggests two shifts from traits associated with short-billed Orange-breasted sunbird pollination: one towards traits associated with moth pollination, and one towards traits associated with pollination by long-billed Malachite sunbirds. The latter shift coincided with the colonization of Namaqualand in which Orange-breasted sunbirds are absent.
Conclusions Erica plukenetii
is characterized by three pollination ecotypes, but only the evolutionary transition from short- to long-billed sunbird pollination can be clearly explained by the Grant–Stebbins model. Corolla length is a key character for both ecotype transitions, while floral scent emission was important for the transition from bird to moth pollination.
Helicoverpa armigera; speciation; benzene propanoids; phylogeny; niche; floral scent; bird pollination; floral trait; ancestral character state; Erica plukenetii; pollination ecotype; Cape flora
Related Articles
Floral odour chemistry defines species boundaries and underpins strong reproductive isolation in sexually deceptive orchids
Peakall, Rod
Whitehead, Michael R.
Annals of Botany
Background and Aims
The events leading to speciation are best investigated in systems where speciation is ongoing or incomplete, such as incipient species. By examining reproductive barriers among incipient sister taxa and their congeners we can gain valuable insights into the relative timing and importance of the various barriers involved in the speciation process. The aim of this study was to identify the reproductive barriers among sexually deceptive orchid taxa in the genus Chiloglottis.
The study targeted four closely related taxa with varying degrees of geographic overlap. Chemical, morphological and genetic evidence was combined to explore the basis of reproductive isolation. Of primary interest was the degree of genetic differentiation among taxa at both nuclear and chloroplast DNA markers. To objectively test whether or not species boundaries are defined by the chemistry that controls pollinator specificity, genetic analysis was restricted to samples of known odour chemistry.
Key Results
Floral odour chemical analysis was performed for 600+ flowers. The three sympatric taxa were defined by their specific chiloglottones, the semiochemicals responsible for pollinator attraction, and were found to be fully cross-compatible. Multivariate morphometric analysis could not reliably distinguish among the four taxa. Although varying from very low to moderate, significant levels of genetic differentiation were detected among all pairwise combinations of taxa at both nuclear and chloroplast loci. However, the levels of genetic differentiation were lower than expected for mature species. Critically, a lack of chloroplast DNA haplotype sharing among the morphologically indistinguishable and most closely related taxon pair confirmed that chemistry alone can define taxon boundaries.
The results confirmed that pollinator isolation, mediated by specific pollinator attraction, underpins strong reproductive isolation in these taxa. A combination of large effective population sizes, initial neutral mutations in the genes controlling floral scent, and a pool of available pollinators likely drives diversity in this system.
Chiloglottis; orchid; Orchidaceae; sexual deception; floral odour; pollination; 2,5-dialkylcyclohexane-1,3-diones; pollinator-driven speciation; population genetic analysis; microsatellites; chloroplast DNA; cpSSRs
Related Articles
Matching floral and pollinator traits through guild convergence and pollinator ecotype formation
Newman, Ethan
Manning, John
Anderson, Bruce
Annals of Botany
Background and Aims
Pollinator landscapes, as determined by pollinator morphology/behaviour, can vary inter- or intraspecifically, imposing divergent selective pressures and leading to geographically divergent floral ecotypes. Assemblages of plants pollinated by the same pollinator (pollinator guilds) should exhibit convergence of floral traits because they are exposed to similar selective pressures. Both convergence and the formation of pollination ecotypes should lead to matching of traits among plants and their pollinators.
We examined 17 floral guild members pollinated in all or part of their range by Prosoeca longipennis, a long-proboscid fly with geographic variation in tongue length. Attractive floral traits such as colour, and nectar properties were recorded in populations across the range of each species. The length of floral reproductive parts, a mechanical fit trait, was recorded in each population to assess possible correlation with the mouthparts of the local pollinator. A multiple regression analysis was used to determine whether pollinators or abiotic factors provided the best explanation for variation in floral traits, and pollinator shifts were recorded in extralimital guild member populations.
Key Results
Nine of the 17 species were visited by alternative pollinator species in other parts of their ranges, and these displayed differences in mechanical fit and attractive traits, suggesting putative pollination ecotypes. Plants pollinated by P. longipennis were similar in colour throughout the pollinator range. Tube length of floral guild members co-varied with the proboscis length of P. longipennis.
Pollinator shifts have resulted in geographically divergent pollinator ecotypes across the ranges of several guild members. However, within sites, unrelated plants pollinated by P. longipennis are similar in the length of their floral parts, most probably as a result of convergent evolution in response to pollinator morphology. Both of these lines of evidence suggest that pollinators play an important role in selecting for certain floral traits.
Coevolution; ecotype; floral guild; geographic variation; pollination; proboscis length; Prosoeca longipennis; specialization; speciation; trait matching; tube length
Related Articles
A pollinator shift explains floral divergence in an orchid species complex in South Africa
Peter, Craig I.
Johnson, Steven D.
Annals of Botany
Background and Aims
Floral diversification driven by shifts between pollinators has been one of the key explanations for the radiation of angiosperms. According to the Grant–Stebbins model of pollinator-driven speciation, these shifts result in morphologically distinct 'ecotypes' which may eventually become recognizable as species. The current circumscription of the food-deceptive southern African orchid Eulophia parviflora encompasses a highly variable monophyletic species complex. In this study, two forms were identified within this complex that differ in distribution, floral morphology, scent chemistry and phenology, and a test was made of whether these differences represent adaptations for different pollinators.
Methods and Results
Multivariate analysis of floral and vegetative traits revealed that there are at least two discrete morphological forms in the species complex. Field observations revealed that each form is pollinated by a different insect species, and thus represent distinct ecotypes. The early-flowering coastal form which has long spurs and floral scent dominated by sesquiterpene compounds is pollinated exclusively by the long-tongued bee Amegilla fallax (Apidae, Anthophorinae), while the late-flowering inland form with short spurs and floral scent dominated by benzenoid compounds is pollinated exclusively by the beetle Cyrtothyrea marginalis (Cetoniinae; Scarabaeidae). Choice experiments in a Y-maze olfactometer showed that beetles are preferentially attracted to the scent of the short-spurred form. A spur-shortening experiment showed that long spurs are required for effective pollination of the bee-pollinated form. Although it was initially thought likely that divergence occurred across a geographical pollinator gradient, plants of the long-spurred form were effectively pollinated when transplanted to an inland locality outside the natural coastal range of this form. Thus, the underlying geographical basis for the evolution of ecotypes in the E. parviflora complex remains uncertain, although early flowering in the long-spurred form to exploit the emergence of naïve bees may restrict this form to coastal areas where there is no frost that would damage flower buds. Later flowering of the short-spurred form coincides closely with the emergence of the pollinating beetles following winter frosts.
This study identifies a shift between bee and beetle pollination as the main driver of floral divergence in an orchid species complex. Floral scent and spur length appear to be key traits in mediating this evolutionary transition.
Grant–Stebbins model; pollinator-driven speciation; pollination ecotypes; scent; Eulophia; Orchidaceae; phenology; beetle pollination; Cetoniinae; bee pollination; Y-maze olfactometer; Amegilla
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BY TODD HUNT New month, new blog location. Welcome to my first Scene Now NEMS360.com blog effort. I wish I could tell you that it will be the best thing you've ever read, but that would be a stretch. Here we go… On tap for this weekend is the annual Winter Jam concert on Sunday. Last year we turned people away at the door as we were filled to capacity. If you plan on attending this year, I suggest arriving early to ensure a seat in the venue. If weather permits feel free to tailgate in the parking lots all afternoon. Don't be surprised if I stop by with an empty plate, though! Other upcoming events include the Harlem Globetrotters on March 16, the Broadway musical Cats on April 2, and Alan Jackson with Jimmy Wayne on April 16. In honor of our new blog location I have decided to add a new feature: the song of the week. Sometimes it might be related to events we have in the building; other times it will just be whatever's stuck in my head while I type. The song for this week is "When The Levee Breaks" by Led Zeppelin. Why that song? I can't get the drum beat out of my head. Of course it's been stuck there for about thirty years so I don't think it will be leaving anytime soon… Until next time, Todd
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