Friday, March 26, 2010

New Bird Fossil Hints at More Undiscovered Chinese Treasures

  

Life reconstruction of Longicrusavis houi in what was probably its favored habitat, shallow lake waters. A reconstruction of the fossil specimen itself is reflected in the water. (Credit: Illustration by Stephanie Abramowicz, Dinosaur Institute, Natural History Museum of Los Angeles County.)

New Bird Fossil Hints at More Undiscovered Chinese Treasures

ScienceDaily (Mar. 25, 2010) — The study of Mesozoic birds and the dinosaur-bird transition is one of the most exciting and vigorous fields in vertebrate paleontology today. A newly described bird from the Jehol Biota of northeast China suggests that scientists have only tapped a small proportion of the birds and dinosaurs that were living at that time, and that the rocks still have many secrets to reveal.


"The study of Mesozoic birds is currently one of the most exciting fields; new discoveries continue to drastically change how we view them," said Jingmai O'Connor, lead author of the study. The article appeared in the March issue of the Journal of Vertebrate Paleontology.

The new bird, named "Longicrusavis houi," belongs to a group of birds known as ornithuromorphs (Ornithuromorpha), which are rare in rocks of this age. Ornithuromorphs are more closely related to modern birds than are most of the other birds from the Jehol Biota.

"Longicrusavis adds to the magnificent diversity of ancient birds, many of them sporting teeth, wing claws, and long bony tails, that recently have been unearthed from northeastern China," said Luis Chiappe, a co-author of the study.

Along with a bird described five years ago, Longicrusavis provides evidence for a new, specialized group of small birds that diversified during the Early Cretaceous between about 130 and 120 million years ago.
"The new discovery adds information not only on the diversity these birds, but also on the possible lakeshore environment in which this bird lived," said co-author Gao Ke-Qin.

The legs of this new species are unusually long, suggesting that it spent much of its time wading in the shallows of ancient lakes. The name "Longicrusavis" means "long-shin bird," highlighting this important aspect of the new specimen. The presence of ancient birds in this habitat suggests that modern birds might have originated from an ancestor that was adapted for life near rivers and lakes.

Previously undescribed feather impressions from a closely related species suggest that both it and Longicrusavis had a long, fan-shaped tail. These are the oldest species to have such a tail, which likely increased flying performance.

The rocks of the Yixian Formation of northeast China have produced a spectacular array of fossils in recent years including fishes, birds, mammals, invertebrates, and dinosaurs. These fossils are collectively are known as the Jehol Biota and they are remarkable because, in many instances, they preserve soft tissues such as feathers or hair in addition to teeth and bones. "The Jehol Biota never fails to stop giving, and the research to be done on these fossils is virtually endless!" said O'Connor.

Story Source:
Adapted from materials provided by Society of Vertebrate Paleontology.

Journal Reference:
  1. O'Connor, J. K., K-Q Gao, and L. M. Chiappe. A New Ornithuromorph (Aves: Ornithothoraces) Bird from the Jehol Group Indicative of Higher-Level Diversity. Journal of Vertebrate Paleontology, 2010; 30 (2): 311-321 DOI: 10.1080/02724631003617498
Society of Vertebrate Paleontology. "New Bird Fossil Hints at More Undiscovered Chinese Treasures." ScienceDaily 25 March 2010. 26 March 2010 <http://www.sciencedaily.com­ /releases/2010/03/100324233003.htm>.

Thursday, March 11, 2010

Suit Filed to Save Penguins at Risk From Global Warming and Fisheries





For Immediate Release, March 9, 2010

Contact:  Catherine Kilduff, Center for Biological Diversity, (415) 644-8580
Todd Steiner/Teri Shore, Turtle Island Restoration Network, (415) 663- 8590 x 103/104 
  

Suit Filed to Save Penguins at Risk From Global Warming and Fisheries

SAN FRANCISCO— The Center for Biological Diversity and Turtle Island Restoration Network (TIRN) today sued the Obama administration for illegally delaying protection of penguins under the Endangered Species Act. The Interior Department failed to meet its December 19, 2009 deadline to list seven penguin species at risk of extinction due to climate change and commercial fisheries. These penguins will not receive desperately needed Endangered Species Act protections until Interior finalizes the listings.

“While sea ice melts and oceans warm, the Obama administration is stuck like a deer in the headlights. Instead of saving penguins from the leviathan of global warming while it still can,” said Catherine Kilduff, a Center attorney, “our government is dragging its feet.”

“Penguins should be marching toward recovery, not extinction. These amazing species face a double whammy from the threats brought by climate change and industrial fisheries that deplete the penguins’ food supply and entangle and drown the penguins in longlines and other destructive fishing gear. They deserve protection under the Endangered Species Act,” said Todd Steiner, biologist and executive director of TIRN.

In 2006 the Center filed a petition to list 12 penguin species under the U.S. Endangered Species Act. In December 2008, the Interior Department proposed listing seven of those species as threatened or endangered – African, Humboldt, yellow-eyed, white-flippered, Fiordland crested, and erect-crested penguins as well as a few populations of the southern rockhopper – while denying listing to emperor and northern rockhopper penguins despite scientific evidence that they also are threatened by climate change.
Today’s lawsuit challenges the Interior Department’s illegal delay in finalizing the listing of the seven proposed penguin species; the Center and TIRN also intend to file suit against Interior for denying protections to emperor and rockhopper penguins. Warming oceans, melting sea ice, and fishery harvests have wreaked havoc on penguins’ food supply: krill, an essential nutrient for penguins, whales, and seals, has declined by up to 80 percent since the 1970s over large areas of the Southern Ocean. Reduced food supply has diminished populations of species ranging from southern rockhoppers and Humboldt penguins of South American islands to the African penguin in southern Africa.

Endangered Species Act listing would protect penguins from multiple threats, raise awareness of their plight, and increase research funding. Federal approval of fishing permits for U.S.-flagged vessels on the high seas, for example, would require analysis and minimization of impacts on penguins. The Act also has a key role in managing greenhouse gas pollution by compelling federal agencies to look at the impact of the emissions generated by their activities on listed species and reduce those impacts.

For more information on penguins, please see: http://www.biologicaldiversity.org/species/birds/penguins/index.html.

Sunday, March 7, 2010

Jellyfish to replace penguins thanks to global warming

Penguins in Antarctica to be replaced by jellyfish due to global warming

Rising temperatures in the oceans around Antarctica could lead to the continent's penguins being replaced by jellyfish, scientists have warned.

 

A Gentoo penguin feeding her young krill: A Gentoo penguin feeding her young krill
A Gentoo penguin feeding her young krill Photo: ALEX BENWELL
  
The results of the largest ever survey of Antarctic marine life reveal melting sea ice is decimating krill populations, which form an integral part of penguins' diets. The six-inch-long invertebrates, also eaten by other higher Southern Ocean predators such as whales and seals, are being replaced by smaller crustaceans known as copepods.
These miniscule copepods, measuring just half a millimetre long, are too small for penguins but ideal for jellyfish and other similarly tentacled predators. Huw Griffiths, a marine biologist, said the shifting food web, coupled with shrinking ice sheet breeding grounds, could seriously affect the world's favourite Antarctic animal. Mr Griffiths, of British Antarctic Survey (BAS), said: ''Marine animals spent millions of years adapting to the freezing, stable conditions of the Antarctic waters and they are highly sensitive to change.

''The polar oceans are rich in biodiversity. But if species are unable to move or adapt to new conditions they could ultimately die out. Copepods are 120 times smaller than krill, which is inevitably going to affect all the things that feed in that area. Penguins, sea birds, whales are all used to catching large items of prey. But creatures with tentacles - like jellyfish are going to have more food value out of smaller prey.This kind of predator will do better in this warmer environment. We already have huge numbers of amazing looking jellyfish. They are not quite invading but numbers will go up to the point where they become the dominant group. And if the waters continue to warm there will not only be a shift between species that are already there, but new species will be able to come into the area.''

Mr Griffiths said species of small invertebrates, fish and crabs that cannot currently tolerate the -2C temperatures in the Antarctica waters might start soon start to appear. Any decrease in sea ice will inevitably affect the delicate balance of the Antarctic marine food chain. For creatures such as penguins who lives on the melting sea ice, a rise in temperatures will also shrink the size of their breeding grounds.

Mr Griffith's research is based ON the Census of Antarctic Marine Life (CAML) and he presented his findings at the American Association for the Advancement of Science (AAAS) in San Diego on Thursday.
The census began in 2005 and will provide the benchmark for future studies on how the diverse sea-floor creatures living in Antarctica's waters will respond to predicted climate change.

More than 6,000 different species living on the sea-floor have been identified so far and more than half of these can only be found on the icy continent. Mr Griffith's work also describes certain creatures such as sea spiders flourish in the Antarctic waters because of the unique environment. The stunning sea spiders in Antarctica are roughly the size of dinner plates, whereas their delicate cousins around the UK coast are no bigger than a little fingernail.

Mr Griffiths added: ''This is a group that has done really well in the cold. Around 20 per cent of the world's population of sea spiders are from Antarctica. ''They are bigger than anywhere else in the world and this is probably because the environment happens to be ideal for them. It makes you realise if the waters warm and other species or predators move in these unique animals will come under competition.''


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