15-year study: When it comes to creating wetlands, Mother Nature is in charge

Fifteen years of studying two experimental wetlands has convinced Bill Mitsch that turning the reins over to Mother Nature makes the most sense when it comes to this area of ecological restoration.

Mitsch, an environment and natural resources professor at Ohio State University, has led the effort to compare the behavior of two experimental marshes on campus – one that was planted in 1994 with wetland vegetation and another that was left to colonize plant and animal life on its own.

Australian tyrannosaur fossil found

Dr Tom H. Rich with the Australian tyrannosauroid fossil. | Image: Jon Augier | Source: Museum VictoriaFossils discovered by Australian scientists have provided the first ever evidence of tyrannosaur dinosaurs in the southern continents. A hip bone found at Dinosaur Cove in Victoria has been identified as belonging to a relative of the infamous Tyrannosaurus rex.

The discovery of the fossil sheds new light on the evolutionary history of this group of dinosaurs and raises the crucial question of why it was only in the northern hemisphere that tyrannosaurs evolved into giant predators like Tyrannosaurus rex. The specimen suggests there may well be more tyrannosaurs on the southern continents.

Global warming threatens plant diversity

Senecio inaequidens, a plant native to the mountains of South Africa, has been spreading rapidly along the roads and railway embankments in Germany since the 1950s.In the coming decades, climate change is set to produce worldwide changes in the living conditions for plants, whereby major regional differences may be expected to occur. Thus today´s cool, moist regions could in future provide habitats for additional species, and in arid and hot regions the climatic prerequisites for a high degree of plant diversity will deteriorate. This is the conclusion reached in a new study by scientists at the Universities of Bonn, Göttingen and Yale, and published in the Proceedings of the Royal Society London. The study was funded by the Academy of Sciences and Literature Mainz and the German Federal Ministry for Education and Research (BMBF).

Marine species get raw deal at CITES

A United Nations meeting on endangered species trade adjourned today after two weeks of negotiations marked by the repeated rejection of proposals to better protect marine species, such as the Atlantic bluefin tuna, corals and several shark species.

Trade issues on marine species failed to attract the necessary support at the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), which meets once every three years.

Time for closer collaboration on wildlife trade

It’s time for joint action and for regulatory bodies to work together to ensure the continued survival of species threatened by wildlife trade, says IUCN at the end of the 15th Meeting of the Conference of the Parties (CoP15) to the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), in Doha, Qatar.

“CITES CoP15 has highlighted the challenges facing this convention as one of the many existing agreements for managing commercially important species sustainably,” says Sue Mainka, Head of IUCN’s delegation to CITES. “However, the decisions taken at CoP15 should stimulate further evolution of CITES including development of tools and mechanisms needed to support efforts to achieve sustainable management of natural resources. Those resources are fundamental elements of our economy and people’s livelihoods.”

Reindeer stop the clock to cope with polar days and nights

Reindeer have 'switched off' their body clocks in order to survive the extreme Arctic seasons of polar day, when the sun stays up all day, and polar night, when the sun does not rise above the horizon at all, scientists have discovered.

The body clock, or circadian clock, is the internal mechanism that drives hormone rhythms - and thus a host other functions - in a rhythmic 24-hour fashion. Light-dark cycles drive hormone rhythms via a circuit that involves the eye and nervous system affecting hormone production, in particular melatonin. In most mammals, this wiring circuit also involves the circadian clock, which is able to drive the hormone rhythms even when there is no light dark cycle.

Genetic analysis gives hope that extinct tortoise species may live again

Thanks to genetic data gleaned from the bones found in a several museum collections, an international team of researchers led by scientists from Yale believes it may be possible to resurrect a tortoise species hunted to extinction by whalers visiting the Galapagos Islands during the early 19th century, before Charles Darwin made his famous visit.

A genetic analysis of 156 tortoises living in captivity and the DNA taken from remains of specimens of the now-extinct Chelonoidis elephantopus revealed that nine are descendants of the vanished species, which once made its home on Floreana Island in the Galapagos. Over a few generations, a selective breeding program among these tortoises should be able to revive the C. elephantopus species, said Adalgisa Caccone, senior research scientist in the department of ecology and evolutionary biology at Yale and senior author of the piece published this week in the online journal PLoS ONE.

New theory on the origin of primates

A new model for primate origins is presented in Zoologica Scripta, published by the Norwegian Academy of Science and Letters and The Royal Swedish Academy of Sciences. The paper argues that the distributions of the major primate groups are correlated with Mesozoic tectonic features and that their respective ranges are congruent with each evolving locally from a widespread ancestor on the supercontinent of Pangea about 185 million years ago.

Michael Heads, a Research Associate of the Buffalo Museum of Science, arrived at these conclusions by incorporating, for the first time, spatial patterns of primate diversity and distribution as historical evidence for primate evolution. Models had previously been limited to interpretations of the fossil record and molecular clocks.

African leaf-eating primates are ‘likely to be wiped out’ by climate change

Monkey species will become ‘increasingly at risk of extinction’ because of global warming, according to new research, published this week. It reveals that populations of monkeys and apes in Africa that depend largely on a diet of leaves may be wiped out by a rise in annual temperatures of two degrees Celsius. The study by researchers from Bournemouth, Roehampton and Oxford Universities suggests that the species most at risk are the already endangered gorillas and colobine monkeys.

The paper, published online by Animal Behaviour, pinpoints which species are most threatened by climate change in a series of new global maps. They show current and predicted distribution patterns of primates, comparing the populations according to their diet and the amount of enforced rest they are predicted to need.

Wild chimps have near human understanding of fire

Jill Pruetz, an ISU associate professor of anthropology, has been studying savanna chimpanzees at her Fongoli research site in Senegal since 2001. Her new study documents how the chimps understand the fire they encounter in the region. Photo by Bob Elbert, ISU News ServiceThe use and control of fire are behavioral characteristics that distinguish humans from other animals. Now, a new study by Iowa State University anthropologist Jill Pruetz reports that savanna chimpanzees in Senegal have a near human understanding of wildfires and change their behavior in anticipation of the fire's movement.

An ISU associate professor of anthropology, Pruetz and Thomas LaDuke, an associate professor of biological sciences at East Stroudsburg (Pa.) University, co-authored the paper, which will be posted online Friday by the American Journal of Physical Anthropology. It will be published in a 2010 edition of the journal.

Australian fossil unlocks secrets to the origin of whales

Mammalodon skull, oblique side view.
Image: Rodney Start
Source: Museum VictoriaDr Fitzgerald’s study, which is published in the Zoological Journal of the Linnean Society, is centred on Mammalodon colliveri, a primitive toothed baleen whale, one of a group of whales that includes the largest animal ever to have lived, the blue whale. Although Mammalodon was discovered in 1932 and named in 1939, it has remained relatively unknown until now.

“Through study of Mammalodon, I hypothesise that it was a bottom-feeding mud-sucker that may have used its tongue and short, blunt snout to suck small prey from sand and mud on the seafloor. This indicates early and varied experimentation in the evolution of baleen whales”, explained Dr Fitzgerald.

Marine scientists discover deepest undersea erupting volcano

An explosion at the West Mata Volcano throws ash and rock, with molten lava glowing below. Photo: NSF/NOAAScientists funded by the National Science Foundation (NSF) and NOAA have recorded the deepest erupting volcano yet discovered – West Mata Volcano – describing high-definition video of the undersea eruption as "spectacular."

"For the first time we have been able to examine, up close, the way ocean islands and submarine volcanoes are born," said Barbara Ransom, program director in NSF's Division of Ocean Sciences. "The unusual primitive compositions of the West Mata eruption lavas have much to tell us."

NASA tech zooms in on water and land

Photo:Dwight Barry/Peninsula CollegeIn a pilot project that could help better manage the planet's strained natural resources, space-age technologies are helping a Washington state community monitor its water availability. NASA satellites and sensors are providing the information needed to make more accurate river flow predictions on a daily basis.

"World leaders are struggling to protect natural resources for future generations," said Jeff Ward, a senior research scientist at the Department of Energy's Pacific Northwest National Laboratory, which is managed by Battelle. "These tools help us sustainably use natural resources while balancing environmental, cultural and economic concerns."

Irrigation decreases, urbanisation increases monsoon rains

Photo:Jaxer/WikimediaA Purdue University scientist has shown man-made changes to the landscape have affected Indian monsoon rains, suggesting that land-use decisions play an important role in climate change.

Monsoon rainfall has decreased over the last 50 years in rural areas where irrigation has been used to increase agriculture in northern India, said Dev Niyogi, an associate professor of agronomy and earth and atmospheric sciences. At the same time, heavily urban areas are seeing an increase in heavy rainfall.

Climate Change – Turn the tide, turn to nature

It's now the time for governments to make robust commitments and a timeline towards achieving a post-2012 deal on climate change.

IUCN, the world's oldest and largest conservation network, urges leaders meeting at UNFCCC COP15 in Copenhagen on 7-18 December to include nature's solutions to reduce emissions and cope with impacts of climate change in a post-2012 deal."Managing nature will play a key role in our ability to cope with the changing climate and reduce emissions," says Julia Marton-Lefèvre, Director General of IUCN.

Tigers, Polar Bears and Blue Fin Tuna Among the Most Threatened Species in 2010

World Wildlife Fund (WWF)has released its annual list of some of the most threatened species around the world, saying that the long-term survival of many animals is increasingly in doubt due to a host of threats, including climate change, and calling for a step up in efforts to save some of the world’s most threatened animals.

WWF’s list of “10 to Watch in 2010” includes such well-known and beloved species as tigers, polar bears, pandas, and rhinos, as well as lesser-known species such as bluefin tuna and mountain gorillas.  WWF scientists say these, and many other species, are at greater risk than ever before because of habitat loss, poaching, and climate change-related threats. This year’s watch list includes five species directly impacted by climate change, as well as the monarch butterfly, the species at the center of an endangered biological phenomenon.  Tigers are at the forefront of this year’s list, with the official Year of the Tiger slated to begin in February 2010.

Ironing out a longstanding geological puzzle

Yifeng Wang holds a piece of banded iron during a visit to an aquarium. Wang and colleagues have proposed an explanation – published recently in Nature Geoscience – for the precipitation of banded iron deposits in the planet's oceans billions of years ago. (Photo by Randy Montoya)Why huge bands of iron formed billions of years ago on Earth’s surface

No one knows why massive formations of banded iron – some ultimately hundreds of kilometers long, like a sleeping giant’s suspenders – mysteriously began precipitating on Earth’s surface about 3.5 billion years ago. Or why, almost 2 billion years later, the precipitation ceased.

Because these deposits carry information about early Earth’s surface conditions and climate changes, as well as provide much of modern industry’s iron resources, interested researchers have cast a wide net in trying to explain why and how these bands formed. But attempts to explain their existence based on seasonal variations, surface temperature changes and episodic seawater mixing all have foundered on assumptions requiring the unexplained oscillations of external forces.

After mastodons and mammoths, a transformed landscape

Roughly 15,000 years ago, at the end of the last ice age, North America's vast assemblage of large animals – including such iconic creatures as mammoths, mastodons, camels, horses, ground sloths and giant beavers – began their precipitous slide to extinction.

And when their populations crashed, emptying a land whose diversity of large animals equalled or surpassed Africa's wildlife-rich Serengeti plains then or now, an entirely novel ecosystem emerged as broadleaved trees once kept in check by huge numbers of big herbivores claimed the landscape. Soon after, the accumulation of woody debris sparked a dramatic increase in the prevalence of wildfire, another key shaper of landscapes.

Mysteriously warm times in Antarctica

A new study of Antarctica's past climate reveals that temperatures during the warm periods between ice ages may have been higher than previously thought.

A new study of Antarctica's past climate reveals that temperatures during the warm periods between ice ages (interglacials) may have been higher than previously thought. The latest analysis of ice core records suggests that Antarctic temperatures may have been up to 6°C warmer than the present day.

Are the Alps growing or shrinking?

Correlation between mountain growth and climate

The Alps are growing just as quickly in height, as they are shrinking. This paradoxical result could be proven by a group of German and Swiss geoscientists. Due to glaciers and rivers about exactly the same amount of material is eroded from the Alp slopes as is regenerated from the deep Earth's crust. The climatic cycles of the glacial period in Europe over the past 2.5 million years have accelerated this erosion process. In the latest volume of the science magazine Tectonophysics ( No. 474, S.236-249) the scientists prove that today's uplifting of the Alps is driven by these strong climatic variations.

The formation of the Alps through the collision of the two continents Africa and Europe began about approximately 55 million years ago. This led to the upthrusting of the highest European mountains, which probably already achieved its greatest height some millions of years ago. At present, however, the Swiss Alps are no longer growing as a result of this tectonic process.

Swiss geodesists, who have already been measuring the Alps with highest accuracy for decades, have observed, however, that the Alp summits, as compared to low land, rise up to one millimetre per year. Over millions of years a considerable height would have to result. But why then are the Alps not as high as the Himalayas? Researchers from the GFZ German Research Centre for Geosciences were able to calculate that mountains eroded concurrently at almost exactly the same speed.

"This mountain erosion cannot even be determined using the highly precise methods of modern geodesy" explains Professor Friedhelm v. Blanckenburg from the GFZ. "We use the rare isotope Beryllium-10, which develops in the land surface via cosmic radiation. The quicker a surface erodes, the fewer isotopes of this type are present therein". Therefore, von Blanckenburg, and the GFZ geoscientist, Dr. Hella Wittmann, have analysed this "cosmogenic" isotope in the sand of the Swiss Alps rivers and, thus, in the direct products of erosion.

How does it come about now that the Alps erode at the same speed that they rise? "Here pure upthrusting forces are at work. It is similar to an iceberg in the sea. If the top melts, the iceberg surfaces out of the water by almost the same share" explains von Blanckenburg. Thus this paradoxical situation with the Alps that through wind, water, glaciers and rock fall, they are being constantly finely eroded from the top but on the other hand, regenerated from the Earth's mantle. This phenomenon, even if already postulated theoretically has now been proven for a complete mountain range for the first time.

Thus, the Alps are constantly rising, although they have been deemed "dead" in a tectonic sense. Instead of plate forces it is the strong climatic variations since the beginning of the so-called quaternary glacial before approximately 2.5 million years, to which mountain slopes in particular have been reacting so sensitively. This holds the Alps in motion.