Warming, not Instability, Caused Ice Sheet Collapse

In 2002, when the massive Larsen-B Ice Shelf in Antarctica splintered and collapsed, it was because of warming from above rather than from instability in the ice below, a new study reports. This finding will surprise scientists who thought that the shelf’s disintegration occurred primarily due to the thinning of the ice shelf and the loss of support by the seafloor beneath it. Rebesco and colleagues revealed that the modern ice sheet grounding line under the Larsen-B Ice Shelf was established 12,000 years ago and has since remained unchanged; it did not retreat significantly in 2002. If the Larsen-B Ice Shelf did not collapse due to grounding line instability, then collapse must have been caused by warming from above, the researchers say. Understanding the role warming temperatures played in the collapse of this ice shelf may help scientists to better project future sea level rise from glaciers elsewhere in Antarctica, the researchers say.

Read more about this research from the 12 September issue of Science here.

[Image courtesy of Michele Rebesco. Please click here for further information.]

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

Warming, not Instability, Caused Ice Sheet Collapse

In 2002, when the massive Larsen-B Ice Shelf in Antarctica splintered and collapsed, it was because of warming from above rather than from instability in the ice below, a new study reports. This finding will surprise scientists who thought that the shelf’s disintegration occurred primarily due to the thinning of the ice shelf and the loss of support by the seafloor beneath it. Rebesco and colleagues revealed that the modern ice sheet grounding line under the Larsen-B Ice Shelf was established 12,000 years ago and has since remained unchanged; it did not retreat significantly in 2002. If the Larsen-B Ice Shelf did not collapse due to grounding line instability, then collapse must have been caused by warming from above, the researchers say. Understanding the role warming temperatures played in the collapse of this ice shelf may help scientists to better project future sea level rise from glaciers elsewhere in Antarctica, the researchers say.

Read more about this research from the 12 September issue of Science here.

[Image courtesy of Michele Rebesco. Please click here for further information.]

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

Recently Evolved Species Cope Better with Changing Land Use

A 12-year field study of birds in Costa Rica shows that older lineages, or species with the longest evolutionary histories, are more likely to go extinct in agricultural landscapes than newer lineages. This finding demonstrates how habitat conversion can actually restructure the tree of life by favoring certain branches over others, and it may inform conservation efforts in the future. Luke Frishkoff and colleagues studied 44 plots of land that represented three different types of land use: forest reserves, which are undisturbed by humans; diversified agricultures, which host different kinds of crops; and intensive monocultures, which host only one kind of crop. They performed surveys of birds, documenting 118,127 sightings of 487 different species, and designed a model to estimate when and where such species disappeared from those landscapes. 

Read more about this research from the 12 September issue of Science here.

[Photo courtesy of Daniel Karp. Please click here for further information.]

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

Recently Evolved Species Cope Better with Changing Land Use

A 12-year field study of birds in Costa Rica shows that older lineages, or species with the longest evolutionary histories, are more likely to go extinct in agricultural landscapes than newer lineages. This finding demonstrates how habitat conversion can actually restructure the tree of life by favoring certain branches over others, and it may inform conservation efforts in the future. Luke Frishkoff and colleagues studied 44 plots of land that represented three different types of land use: forest reserves, which are undisturbed by humans; diversified agricultures, which host different kinds of crops; and intensive monocultures, which host only one kind of crop. They performed surveys of birds, documenting 118,127 sightings of 487 different species, and designed a model to estimate when and where such species disappeared from those landscapes.

Read more about this research from the 12 September issue of Science here.

[Photo courtesy of Daniel Karp. Please click here for further information.]

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

New Fossils Reveal Dino’s Aquatic Adaptations

Spinosaurus aegyptiacus — a meat-eating dinosaur bigger than Tyrannosaurus rex — was a fantastic swimmer, a new fossil study reports. This is a first for dinosaurs, long thought to be terrestrial beasts. Ever since the first fossils of S. aegyptiacus were examined over a century ago, much of our understanding of its morphology and ecology was left to speculation because the first fossils were destroyed during World War II. Now, a much more complete set of fossils suggests that the carnivore was semi-aquatic. Nizar Ibrahim and colleagues describe these new fossils, which include portions of a skull, axial column, pelvic girdle and limbs, from the Kem Kem beds of eastern Morocco. 

Read more about this research from the 11 September issue of Science  here and here.

[Artwork by Davide Bonadonna, Ibrahim et al., Science/AAAS. Click here for further information.]

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

New Fossils Reveal Dino’s Aquatic Adaptations

Spinosaurus aegyptiacus — a meat-eating dinosaur bigger than Tyrannosaurus rex — was a fantastic swimmer, a new fossil study reports. This is a first for dinosaurs, long thought to be terrestrial beasts. Ever since the first fossils of S. aegyptiacus were examined over a century ago, much of our understanding of its morphology and ecology was left to speculation because the first fossils were destroyed during World War II. Now, a much more complete set of fossils suggests that the carnivore was semi-aquatic. Nizar Ibrahim and colleagues describe these new fossils, which include portions of a skull, axial column, pelvic girdle and limbs, from the Kem Kem beds of eastern Morocco.

Read more about this research from the 11 September issue of Science here and here.

[Artwork by Davide Bonadonna, Ibrahim et al., Science/AAAS. Click here for further information.]

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

A woman cares for her 5-year-old grandson, who has malaria, in a hospital in northwestern Zambia. An upsurge in funding for global health over the past 15 years has brought dramatic declines in deaths and illness from malaria and other diseases of the poor. Countries like Zambia are now trying to preserve those gains while tackling new challenges. See page 1256.

[Photo © John Stanmeyer/VII/Corbis] 

Anyone wishing to use the cover of Science must contact AAAS to request permission to do so.

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

A woman cares for her 5-year-old grandson, who has malaria, in a hospital in northwestern Zambia. An upsurge in funding for global health over the past 15 years has brought dramatic declines in deaths and illness from malaria and other diseases of the poor. Countries like Zambia are now trying to preserve those gains while tackling new challenges. See page 1256.

[Photo © John Stanmeyer/VII/Corbis]

Anyone wishing to use the cover of Science must contact AAAS to request permission to do so.

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

Infant Diet Has Lasting Effects on Immune System

Understanding the effects of early diet on immunity may help researchers explain why some people respond differently to vaccines or are more vulnerable to infection or autoimmune disease. Dennis Hartigan-O’Connor, along with Amir Ardeshir and colleagues examined the effects of both breastfeeding and formula feeding on immune function during the first six months of life in infant monkeys. The results hint that commensal gut bacteria — which are shaped by early diet —- leave a lasting imprint on the immune system that may affect how a person responds to infection later in life. 

Read more about this research from the 3 September issue of Science Translational Medicine here.

[Image courtesy of David A. Mills. Please click here for more information.]

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

Infant Diet Has Lasting Effects on Immune System

Understanding the effects of early diet on immunity may help researchers explain why some people respond differently to vaccines or are more vulnerable to infection or autoimmune disease. Dennis Hartigan-O’Connor, along with Amir Ardeshir and colleagues examined the effects of both breastfeeding and formula feeding on immune function during the first six months of life in infant monkeys. The results hint that commensal gut bacteria — which are shaped by early diet —- leave a lasting imprint on the immune system that may affect how a person responds to infection later in life.

Read more about this research from the 3 September issue of Science Translational Medicine here.

[Image courtesy of David A. Mills. Please click here for more information.]

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

How Ocean Microbes Respond to Limited Nutrients

Two new studies advance our understanding of how nutrient availability influences protein production by marine microbes. Mak Saito and colleagues show, for the first time, that they can precisely measure the amounts of specific proteins from individual ocean microbe species at various ocean locations. They collected water samples along a 2,500-mile stretch of Pacific Ocean and their efforts spanned regions with widely different nutrient concentrations. They show how multiple scarce nutrients can together influence ocean microbial communities. In a second study, Shee Yong and colleagues provide new insights about the trace metals that marine plankton require to extract phosphorous from low-phosphorous ocean environments. Together, the studies reveal how ocean microbes respond to limited nutrients. 

Read more about this research from the 5 September issue of Science here.

[Image courtesy of Brian Dimento, University of Connecticut. Please click here for more information.]

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

How Ocean Microbes Respond to Limited Nutrients

Two new studies advance our understanding of how nutrient availability influences protein production by marine microbes. Mak Saito and colleagues show, for the first time, that they can precisely measure the amounts of specific proteins from individual ocean microbe species at various ocean locations. They collected water samples along a 2,500-mile stretch of Pacific Ocean and their efforts spanned regions with widely different nutrient concentrations. They show how multiple scarce nutrients can together influence ocean microbial communities. In a second study, Shee Yong and colleagues provide new insights about the trace metals that marine plankton require to extract phosphorous from low-phosphorous ocean environments. Together, the studies reveal how ocean microbes respond to limited nutrients.

Read more about this research from the 5 September issue of Science here.

[Image courtesy of Brian Dimento, University of Connecticut. Please click here for more information.]

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

Soft, Shape-Shifting Materials

By placing liquid crystals on the surface of a soft, deformable fluid pocket, or vesicle, researchers have designed a new, tunable kind of shape-changing material that mimics some of the remarkable complexity of a living organism. Felix Keber and his colleagues demonstrate how topological constraints can be used to control the non-equilibrium dynamics of active matter, like liquid crystals.

Read more about this research from the 5 September issue of Science here.

[Image courtesy of Christoph Hohmann, Nano Initiative Munich. Please click here for more information.]

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

Soft, Shape-Shifting Materials

By placing liquid crystals on the surface of a soft, deformable fluid pocket, or vesicle, researchers have designed a new, tunable kind of shape-changing material that mimics some of the remarkable complexity of a living organism. Felix Keber and his colleagues demonstrate how topological constraints can be used to control the non-equilibrium dynamics of active matter, like liquid crystals.

Read more about this research from the 5 September issue of Science here.

[Image courtesy of Christoph Hohmann, Nano Initiative Munich. Please click here for more information.]

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

Greenland Ice Cores Reveal Long-Sought Temperature Data

A new study suggests Greenland started warming about 19,000 years ago, along with the rest of the Northern Hemisphere, despite studies that had suggested Greenland warmed much later. The researchers also suggest that temperatures changed more in central Greenland than in the northwest and that such abrupt climate change is heavily dependent upon the seasons — largely a winter phenomenon. 

Read more about this research from the 5 September issue of Science here.

[Image courtesy of Helle Kjaer. Please click here for more information.]

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

Greenland Ice Cores Reveal Long-Sought Temperature Data

A new study suggests Greenland started warming about 19,000 years ago, along with the rest of the Northern Hemisphere, despite studies that had suggested Greenland warmed much later. The researchers also suggest that temperatures changed more in central Greenland than in the northwest and that such abrupt climate change is heavily dependent upon the seasons — largely a winter phenomenon.

Read more about this research from the 5 September issue of Science here.

[Image courtesy of Helle Kjaer. Please click here for more information.]

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

Secret to Regrowing Cartilage Might Be Found in the Nose

Cells from the nose are especially good at regrowing cartilage in other parts of the body, new research shows. Aside from repairing cartilage in joints after traumatic injuries like sports accidents, these nose cartilage cells could potentially be useful in other fields of regenerative medicine, like plastic/reconstructive surgery, as well as for degenerative diseases like osteoarthritis.

Read more about this research from the 27 August issue of Science Translational Medicine here.

[Video © AAAS/Carla Schaffer. Please click here for more information.]

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

Your Microbial Fingerprint on the Move

Researchers studying the microbial communities that colonize people, places and pets have determined that such microbiota differ greatly from household to household. By characterizing the bacteria in our unique environments, they are starting to map out how interactions between people and the bacteria that surround them might affect human health. When people pack up their belongings and move houses, they also move their unique microbiological “auras”, Simon Lax and colleagues report in this study.

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

[Video © Argonne National Laboratory. 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.