Sequenced Ebola Strains Inform Aspects of Current Epidemic

Researchers have sequenced 99 Ebola virus genomes from patients in West Africa, the site of the largest Ebola outbreak ever recorded. Their results provide insights into how and when Ebola virus (EBOV) entered human populations in the 2014 outbreak and may guide approaches for managing Ebola’s spread and understanding therapeutic targets. While previous outbreaks of Ebola were confined to Middle Africa, the 2014 outbreak began in the West African nation of Guinea, then spreading to Sierra Leone, Liberia and Nigeria. As in all other EBOV outbreaks, the viral strains involved carry distinctive genetic variations. Gire et al. determined that this year’s outbreak likely spread from Middle Africa within the last decade. Although there are not immediate treatment implications from knowing these viral sequences, this information is critical to scientists working to understand the disease.

Read more about this research from the 28 August issue of Science Express here and the related News story.

[Image courtesy of Stephen Gire. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

Sequenced Ebola Strains Inform Aspects of Current Epidemic

Researchers have sequenced 99 Ebola virus genomes from patients in West Africa, the site of the largest Ebola outbreak ever recorded. Their results provide insights into how and when Ebola virus (EBOV) entered human populations in the 2014 outbreak and may guide approaches for managing Ebola’s spread and understanding therapeutic targets. While previous outbreaks of Ebola were confined to Middle Africa, the 2014 outbreak began in the West African nation of Guinea, then spreading to Sierra Leone, Liberia and Nigeria. As in all other EBOV outbreaks, the viral strains involved carry distinctive genetic variations. Gire et al. determined that this year’s outbreak likely spread from Middle Africa within the last decade. Although there are not immediate treatment implications from knowing these viral sequences, this information is critical to scientists working to understand the disease.

Read more about this research from the 28 August issue of Science Express here and the related News story.

[Image courtesy of Stephen Gire. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

Early Peopling of the North American Arctic

[Image courtesy of Claus Andreasen. Please click here for more information.]

View image slideshow, with captions and credits, here.

Using a combination of data from ancient and modern individuals, researchers have provided one of the clearest pictures yet of the population history of the North American Arctic. They believe the first inhabitants may have arrived 6,000 years ago, having crossed the Bering Strait from Siberia. The Arctic residents represent two distinct migrations, the Paleo-Eskimos, who showed up first and exhibited varied archaeological cultures, and the Neo-Eskimos, who appeared almost 4,000 years later. The researchers collected preserved bone, teeth, and hair samples of more than 150 ancient humans from Arctic Siberia, Alaska, Canada and Greenland, and analyzed their mitochondrial DNA. To draw comparisons between these ancient peoples and modern groups, the researchers sequenced the genomes of seven living individuals from the region. 

Read more about this research from the 29 August issue of Sciencehere.

© 2014 American Association for the Advancement of Science. All Rights Reserved.

Early Peopling of the North American Arctic

[Image courtesy of Claus Andreasen. Please click here for more information.]

View image slideshow, with captions and credits, here.

Using a combination of data from ancient and modern individuals, researchers have provided one of the clearest pictures yet of the population history of the North American Arctic. They believe the first inhabitants may have arrived 6,000 years ago, having crossed the Bering Strait from Siberia. The Arctic residents represent two distinct migrations, the Paleo-Eskimos, who showed up first and exhibited varied archaeological cultures, and the Neo-Eskimos, who appeared almost 4,000 years later. The researchers collected preserved bone, teeth, and hair samples of more than 150 ancient humans from Arctic Siberia, Alaska, Canada and Greenland, and analyzed their mitochondrial DNA. To draw comparisons between these ancient peoples and modern groups, the researchers sequenced the genomes of seven living individuals from the region.

Read more about this research from the 29 August issue of Science
here.

© 2014 American Association for the Advancement of Science. All Rights Reserved.

Corals and Reef Fish Follow Their Noses

Efforts to restore degraded coral reefs that have been overrun by seaweed could be complicated by some new findings. Danielle Dixson and colleagues studied coral larvae and young reef fish from the coastal waters of Fiji and found that both of these aquatic drifters were attracted to chemical signals released by healthy corals and repulsed by similar cues coming from seaweed. The researchers compared water from protected areas, where fishing had been outlawed, to water from non-protected areas, where few fish—but lots of seaweed—lived. Time and time again, the researchers found that their young corals and fish chose to explore the water from protected areas while avoiding as best they could the water from non-protected areas. 

Read more about this research from the 22 August issue of Science here.

[Image courtesy of Danielle Dixson. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

Corals and Reef Fish Follow Their Noses

Efforts to restore degraded coral reefs that have been overrun by seaweed could be complicated by some new findings. Danielle Dixson and colleagues studied coral larvae and young reef fish from the coastal waters of Fiji and found that both of these aquatic drifters were attracted to chemical signals released by healthy corals and repulsed by similar cues coming from seaweed. The researchers compared water from protected areas, where fishing had been outlawed, to water from non-protected areas, where few fish—but lots of seaweed—lived. Time and time again, the researchers found that their young corals and fish chose to explore the water from protected areas while avoiding as best they could the water from non-protected areas.

Read more about this research from the 22 August issue of Science here.

[Image courtesy of Danielle Dixson. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

A Signature of One of the Universe’s First Stars?

Researchers may have finally found a star that chemically recorded the supernova of a population III star — one of the first stars in the universe. Wako Aoki and colleagues say that a very metal-poor star known as SDSS J0018-0939 was likely enriched by such a supernova and thereby imprinted with the signature of a population III star. The researchers used the Sloan Digital Sky Survey in the United States and the Subaru Telescope in Japan to find that SDSS J0018-0939 had peculiar patterns of elemental abundances that don’t conform to any particular model of supernova. Their analysis suggests that the progenitor of SDSS J0019-0930 would have had a mass approximately 140 times the mass of the Sun. 

Read more about this research from the 22 August issue of Science here.

[Courtesy of National Astronomical Observatory of Japan. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

A Signature of One of the Universe’s First Stars?

Researchers may have finally found a star that chemically recorded the supernova of a population III star — one of the first stars in the universe. Wako Aoki and colleagues say that a very metal-poor star known as SDSS J0018-0939 was likely enriched by such a supernova and thereby imprinted with the signature of a population III star. The researchers used the Sloan Digital Sky Survey in the United States and the Subaru Telescope in Japan to find that SDSS J0018-0939 had peculiar patterns of elemental abundances that don’t conform to any particular model of supernova. Their analysis suggests that the progenitor of SDSS J0019-0930 would have had a mass approximately 140 times the mass of the Sun.

Read more about this research from the 22 August issue of Science here.

[Courtesy of National Astronomical Observatory of Japan. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

The Genome of the Canola Oil Plant

Scientists have sequenced the genome of the plant that gives us canola oil, Brassica napus, and their work reveals insights into the evolution of such plants (which have chromosomes derived from multiple species), as well as the role their evolution plays in agriculture. B. napus was cultivated over 7,000 years ago for oil, food and fodder.  It is adapted to many different climate zones, and it also produces high seed oil content and low amounts of undesirable chemicals called glucosinolates that cause toxins to build in animal feed. To explore how allopolyploid evolution of this plant contributed to its value in agriculture, Boulos Chaloub and colleagues assembled a draft sequence of B. napus. They observed that the B. rapa and B. oleracea  sub-components continuously exchange corresponding genetic material. Some of these gene conversion events appear to have been selected by humans as part of crop improvement, the researchers say. 

Read more about this research from the 22 August issue of Science here.

[Image © Jean Weber, INRA. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

The Genome of the Canola Oil Plant

Scientists have sequenced the genome of the plant that gives us canola oil, Brassica napus, and their work reveals insights into the evolution of such plants (which have chromosomes derived from multiple species), as well as the role their evolution plays in agriculture. B. napus was cultivated over 7,000 years ago for oil, food and fodder. It is adapted to many different climate zones, and it also produces high seed oil content and low amounts of undesirable chemicals called glucosinolates that cause toxins to build in animal feed. To explore how allopolyploid evolution of this plant contributed to its value in agriculture, Boulos Chaloub and colleagues assembled a draft sequence of B. napus. They observed that the B. rapa and B. oleracea sub-components continuously exchange corresponding genetic material. Some of these gene conversion events appear to have been selected by humans as part of crop improvement, the researchers say.

Read more about this research from the 22 August issue of Science here.

[Image © Jean Weber, INRA. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

How Hummingbirds Regained a Sweet Tooth

Hummingbirds detect sugars using a transformed taste receptor — one that detects the savory umami taste in all other vertebrates, new research reports. This modification helped hummingbirds to sense nectar, a change that allowed them to exploit a distinct environmental niche compared to other birds. To explain the basis of this behavior, Maude Baldwin and colleagues scanned whole-genome sequences of ten bird species, including hummingbirds, looking for genes encoding the non-sweet and sweet taste receptor components, respectively. As expected, they only found the former. The researchers propose the hummingbird adapted to regain the sweet taste perception lost in other birds. This allowed hummingbirds to feed on a resource not used by other avian species, the authors say. 

Read more about this research from the 22 August issue of Science here.

[Image courtesy of Maude W. Baldwin. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

How Hummingbirds Regained a Sweet Tooth

Hummingbirds detect sugars using a transformed taste receptor — one that detects the savory umami taste in all other vertebrates, new research reports. This modification helped hummingbirds to sense nectar, a change that allowed them to exploit a distinct environmental niche compared to other birds. To explain the basis of this behavior, Maude Baldwin and colleagues scanned whole-genome sequences of ten bird species, including hummingbirds, looking for genes encoding the non-sweet and sweet taste receptor components, respectively. As expected, they only found the former. The researchers propose the hummingbird adapted to regain the sweet taste perception lost in other birds. This allowed hummingbirds to feed on a resource not used by other avian species, the authors say.

Read more about this research from the 22 August issue of Science here.

[Image courtesy of Maude W. Baldwin. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

For Polio, Two Vaccines Are Better than One

Using both polio vaccines could help speed the global eradication of polio, a new study reports. The study, done in Indian children already given the live polio vaccine (OPV), shows that a single dose of the inactivated vaccine (IPV) boosts immunity more effectively than an additional live vaccine dose. The results could help resolve controversy over vaccine choice as researchers work to hasten elimination of final poliovirus reservoirs. In certain parts of the globe, like Syria and Iraq, polio is proving difficult to eradicate. The work of Jafari and colleagues is guiding the development of strategies to accelerate the eradication of the poliovirus.

Read more about this research from the 22 August issue of Science here.

[Video © Science/AAAS]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

GPS: A New Way to Monitor Drought

GPS measurements of tiny uplifts in the Earth’s crust have helped scientists estimate groundwater depletion in the western United States, where drought has been severe since 2013. This novel approach to drought monitoring captures a component of the water cycle — variations in underground water levels — that scientists haven’t known much about. Although they can measure precipitation and surface water levels with relative ease, measuring groundwater levels, including those in aquifers, is more challenging. This is largely because terrestrial water storage, or TWS, is monitored at a limited number of locations. At these stations, GPS devices attached to solid rock or anchored a few meters below the soil measure displacement in the Earth’s crust caused by water loss. Adrian Borsa et al. took advantage of these GPS stations to better understand the extent of groundwater depletion from the Rockies to the Pacific Coast. They analyzed the past 11 years of daily crustal uplift estimated from regional GPS stations and used this data to map the impact of drought on local aquifers. The deficit so far in the western U.S. is 240 gigatons of water — the equivalent of a 10 centimeter layer of water across the entire region. Certain areas of California fare much worse, the researchers found, having local depletions up to five times the regional average. 

Read more about this research from the 22 August 2014 issue of Science here.

[Image courtesy of Andre Basset, UNAVCO. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

GPS: A New Way to Monitor Drought

GPS measurements of tiny uplifts in the Earth’s crust have helped scientists estimate groundwater depletion in the western United States, where drought has been severe since 2013. This novel approach to drought monitoring captures a component of the water cycle — variations in underground water levels — that scientists haven’t known much about. Although they can measure precipitation and surface water levels with relative ease, measuring groundwater levels, including those in aquifers, is more challenging. This is largely because terrestrial water storage, or TWS, is monitored at a limited number of locations. At these stations, GPS devices attached to solid rock or anchored a few meters below the soil measure displacement in the Earth’s crust caused by water loss. Adrian Borsa et al. took advantage of these GPS stations to better understand the extent of groundwater depletion from the Rockies to the Pacific Coast. They analyzed the past 11 years of daily crustal uplift estimated from regional GPS stations and used this data to map the impact of drought on local aquifers. The deficit so far in the western U.S. is 240 gigatons of water — the equivalent of a 10 centimeter layer of water across the entire region. Certain areas of California fare much worse, the researchers found, having local depletions up to five times the regional average.

Read more about this research from the 22 August 2014 issue of Science here.

[Image courtesy of Andre Basset, UNAVCO. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

Particles captured by the Stardust Spacecraft

A preliminary examination of particles captured by the Stardust spacecraft — a probe that was launched by NASA in 1999 to sample the dust in a comet’s wake and in the interstellar medium — suggests that seven of the particles recently returned by the probe have their origins outside the solar system. If confirmed, these seven dust particles will represent the first specks of interstellar dust to be brought back to Earth. Andrew Westphal and colleagues — along with citizen scientists around the world — studied the microscopic impacts that particles made on aerogel tiles and pieces of aluminum foil that were exposed to the interstellar medium for 195 days as the Stardust spacecraft made its homeward journey. 

Read more about this research from the 15 August issue of Science  here.

[Image courtesy of Zack Gainsforth. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

Particles captured by the Stardust Spacecraft

A preliminary examination of particles captured by the Stardust spacecraft — a probe that was launched by NASA in 1999 to sample the dust in a comet’s wake and in the interstellar medium — suggests that seven of the particles recently returned by the probe have their origins outside the solar system. If confirmed, these seven dust particles will represent the first specks of interstellar dust to be brought back to Earth. Andrew Westphal and colleagues — along with citizen scientists around the world — studied the microscopic impacts that particles made on aerogel tiles and pieces of aluminum foil that were exposed to the interstellar medium for 195 days as the Stardust spacecraft made its homeward journey.

Read more about this research from the 15 August issue of Science here.

[Image courtesy of Zack Gainsforth. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

A swarm of a thousand robots

Inspired by swarming insects, like ants or bees, researchers have created a swarm of 1,024 small robots that can communicate with each other and organize themselves into shapes, like stars or letters of the alphabet, without any help from humans. Robotic swarms like this have normally been limited to just dozens or hundreds of robots. But, Michael Rubenstein and colleagues have set a new record with their tiny machines, called Kilobots. 

Read more about this research from the 15 August issue of Science here.

[Image courtesy of Michael Rubenstein,Harvard University. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

A swarm of a thousand robots

Inspired by swarming insects, like ants or bees, researchers have created a swarm of 1,024 small robots that can communicate with each other and organize themselves into shapes, like stars or letters of the alphabet, without any help from humans. Robotic swarms like this have normally been limited to just dozens or hundreds of robots. But, Michael Rubenstein and colleagues have set a new record with their tiny machines, called Kilobots.

Read more about this research from the 15 August issue of Science here.

[Image courtesy of Michael Rubenstein,Harvard University. Please click here for more information.]

© 2014 American Association for the Advancement of Science. All Rights Reserved.

© 2014 American Association for the Advancement of Science. All Rights Reserved.