Thursday, February 24, 2011

S. Rockhopper Gains Protection from Salazar

Southern rockhopper penguins
Photo: mbz1 GNU Free lic.
  • February 23rd, 2011 8:58 pm ET
  • Jean Williams
  • Environmental Policy Examiner
As a result of pressure from the environmental organizations, Center for Biological Diversity and Turtle Island Restoration Network, the Interior Department announced on Tuesday that New Zealand-Australia populations of southern rockhopper penguin would finally get listed as a “threatened” species for protection under the Endangered Species Act. The listing followed a legal settlement with the two organizations. Although it is not an “endangered” listing, it will increase funding for research and conservation and additional oversight to federal activities that could result in harm to the existing rockhopper population.
“These hardy penguins survive on remote, stormy, sub-Antarctic islands in the Southern Ocean, practically at the edge of the world, and yet they may not survive climate change,” said Catherine Kilduff, an attorney at the Center, which first petitioned to protect the rockhoppers and 11 other penguin species in 2006. “Endangered Species Act protections can begin to address this threat.”
According to the Center for Biological Diversity press release, Rockhopper penguins, named for the way they hop from boulder to boulder, are widespread — breeding on islands off South America, Africa, Australia and New Zealand — but the penguins listed today have declined by more than 90 percent since the early 1940s. Changes to the marine environment, such as increases in sea-surface temperatures and reduced prey availability, are the primary threat to these colonies.
“These penguins have adapted to an inhospitable environment over hundreds of years, but the combination of ocean warming and commercial fishing may prove to be too much,” said Todd Steiner, biologist and executive director of TIRN. “Through this listing, the government is acknowledging that our oceans are sick and taking a first step to protect penguins and their watery world.”
The Center predicts that by mid-century, if greenhouse gas emissions remain on their current trajectory, climate change will commit one-third of the world’s animal and plant species to extinction. The threatened southern rockhopper penguin joins six other recently protected penguins: the African penguin, the Humboldt penguin of Chile and Peru and four other New Zealand penguins (the yellow-eyed, white-flippered, Fiordland crested and erect-crested). Interior Department Secretary Ken Salazar has a dismal record on listing species for ESA protection and rarely does so, without pressure from conservation groups. More information on the plight of the penguins

Wednesday, February 23, 2011

Southern Rockhopper Penguins Listed as Threatened Species; Climate Change Protections Needed




For Immediate Release, February 22, 2011

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

Southern Rockhopper Penguins Listed as Threatened Species; Climate Change Protections Needed

Rockhopper penguin
Southern rockhopper penguin photo © Larry Master/ MasterImages.org. More images are available here.
SAN FRANCISCO— The Interior Department announced today that the New Zealand-Australia populations of the southern rockhopper penguin, among the world’s smallest penguins, will be listed as threatened under the U.S. Endangered Species Act. The listing will raise awareness of the rockhoppers’ plight, increase research and conservation funds, and offer added oversight of U.S.-government-approved activities that could hurt the birds. It follows a legal settlement with the Center for Biological Diversity and Turtle Island Restoration Network (TIRN) over delays in protecting the penguin.

“These hardy penguins survive on remote, stormy, sub-Antarctic islands in the Southern Ocean, practically at the edge of the world, and yet they may not survive climate change,” said Catherine Kilduff, an attorney at the Center, which first petitioned to protect the rockhoppers and 11 other penguin species in 2006. “Endangered Species Act protections can begin to address this threat.”

“These penguins have adapted to an inhospitable environment over hundreds of years, but the combination of ocean warming and commercial fishing may prove to be too much,” said Todd Steiner, biologist and executive director of TIRN. “Through this listing, the government is acknowledging that our oceans are sick and taking a first step to protect penguins and their watery world.”

By mid-century, if greenhouse gas emissions remain on their current trajectory, climate change will commit one-third of the world’s animal and plant species to extinction. The threatened southern rockhopper penguin joins six other recently protected penguins: the African penguin, the Humboldt penguin of Chile and Peru and four other New Zealand penguins (the yellow-eyed, white-flippered, Fiordland crested and erect-crested).
Rockhopper penguins, named for the way they hop from boulder to boulder, are widespread — breeding on islands off South America, Africa, Australia and New Zealand — but the penguins listed today have declined by more than 90 percent since the early 1940s. Changes to the marine environment, such as increases in sea-surface temperatures and reduced prey availability, are the primary threat to these colonies.

The threatened penguins breed on Macquarie, Campbell, Auckland and Antipodes islands, which are ecologically and geographically unique as well as historically high-quality habitat. The Campbell Island southern rockhopper population was once one of the largest in the world, but has experienced the most severe declines.

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

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 320,000 members and online activists dedicated to the protection of endangered species and wild places.
Turtle Island Restoration Network (TIRN) is an environmental organization working to protect and restore endangered marine species and the marine environment on which we all depend. Headquartered in California, with offices in Texas and Costa Rica, TIRN is dedicated to swift and decisive action to protect and restore marine species and their habitats and to inspire people in communities all over the world to join us as active and vocal marine species advocates. For more information, visit www.SeaTurtles.org and www.TIRN.net.

Penguins: The luckiest birds alive

Penguins' extraordinary ability to survive in the Antarctic is down to an accident of evolution - the heating system in their wings. Roger Dobson explains

Wednesday, 23 February 2011
A heat retaining adaptation in the birds' wings has ensured their
survival
REX FEATURES
A heat retaining adaptation in the birds' wings has ensured their survival


Penguins may owe their survival in the coldest and most inhospitable place on earth to evolutionary chance during a period of global warming millions of years ago. Far from adapting to the cold in Antarctica, where temperatures can plunge below minus 60C and wind speeds reach in excess of 200mph, they have been able to thrive because of a form of central heating of the wings they evolved when the climate on Earth was hot.
New research shows that when the earth warmed up nearly 50 millions years ago, penguins evolved a wing heating system, a highly efficient heat exchanger. 

The mechanism, which is so effective that the birds have to cool down after vigorous swimming in sub-zero waters, evolved to help the birds keep warm while foraging in ever deeper, ever cooler waters. "Penguins had a lucky break with the evolution of heat retention 49 million years ago, as it allowed them to survive the coming cold," says Dr Daniel Thomas of the University of Otago, New Zealand, who led the study. "The fossil evidence reveals that it evolved during a Greenhouse Earth interval. 

"Its evolution is therefore unrelated to global cooling or development of polar ice sheets, but probably represents an adaptation to foraging beneath the surface in waters at temperate latitudes. As global climate cooled, the heat exchanger was key to the invasion of the much more demanding environments associated with Antarctic ice sheets. The climate has never been so hot as it was back then, nor has it been so cold as in recent millennia, and penguins have weathered it all. We are seeing a dramatic shift in climate, however, and it will be a true test for the thermal tolerances of penguins." 

Penguins probably evolved from flying birds between 50 and 60 million years ago. Exactly why they lost the ability to fly is not known, but the dominant theory is that it was the survival trade-off for perfecting flight beneath the surface of the sea. It became more important to be able to dive and swim for food than to fly, so over time the birds lost the ability to fly, and wings became flippers. 

The first penguins came some time after the Cretaceous-Tertiary or KT mass extinction event, around 65 million years ago when almost all the large vertebrates on Earth – dinosaurs, plesiosaurs, mosasaurs, and pterosaurs – suddenly became extinct for reasons that are still hotly debated. 

After KT, climates warmed with temperatures peaking in the Eocene epoch, around 49 million years ago. Geochemical signals, telltale signs of how the earth once was, suggest that it was much warmer. Sea temperatures were around 25C, and the area around what is now Seymour Island in Antarctica, a major penguin habitat, was a balmy 15C, while parts of the now ice-covered region were subtropical. It has long been believed that penguins gradually adapted to increasingly cold conditions after the area became glaciated about 34 million years ago. 

But the new research, by scientists from New Zealand, America and South Africa, based on analysis of modern penguins and of fossils dating back more than 60 million years, shows that the key anatomical change that was to become pivotal to survival in the extreme cold many years later occurred when global warming reached its peak, 49 millions years ago. In the study, the researchers examined the remains of several types of modern penguins, including the little penguin, yellow-eyed penguin, king penguin, and Humboldt penguin, all of which had died naturally. 

Dissection of the birds showed that each had a major adaptation that allows penguins to forage in cold water, the humeral arterial plexus, a counter current vascular heat exchanger, or CCHE, that limits heat loss through the wing. The core body temperature of a penguin is around 38C. Although blubber and feathers offer some protection to the body, the large wings, with tightly attached skin and little insulation, have a huge surface area. Without protection, heat in the wing or flipper would be rapidly lost to the surrounding colder water or air with the threat of hypothermia and death. Heat is lost 20-30 times faster in water than in air. 

The CCHE is an ingenious web of arteries and veins that stops this happening. Blood is pumped to the wings of birds through a single major artery, but in penguins there are up to five arteries, each of which runs alongside two or more veins. Blood in the arteries being pumped into the wing from the heart is much warmer than that in the veins which is returning from the wing extremities exposed to the cold. Heat from the arterial blood is given to the venous blood, and redirected back to the body instead of being lost to the ocean. It is so effective that penguins emerging from the sea often stick their wings out to the sides in order to cool them down.

But when did it evolve? The results of the dissections show that the presence of this heat exchanger mechanism requires grooves in the bones of the wings to carry the arteries, which should be detectable in fossils. The researchers looked at penguin fossils dating from 62 million years ago for signs of these grooves. In the early period birds there were none, but from around 49 million years ago they are present. At around the same time, other changes and adaptations were taking place that improved buoyancy in the water and reduced drag. Body size increased too, and a hydrofoil wing evolved.

But while all of these changes improved the penguins' abilities for long distance swimming and deep diving, there was a snag. While much of the land was now tropical or subtropical, temperatures in the sea had not increased as much and it was still very cold, and significantly cooler than penguin body temperature.
According to the researchers, it was these longer feeding excursions far from the shore, and spending long periods of time in cold waters, that led to the evolution of the heat exchanger. 

Once equipped with the CCHE, the now flightless penguins were able to travel vast distances, and colonise new areas. And millions of years later, when the earth began to cool, the onboard heat exchanger meant the penguin was uniquely equipped for a successful invasion of icy Antarctic, an environment where it has walked, or waddled tall, ever since.

Ironically, there have been warnings that the penguin is at risk from the effects of global warming, including rising temperatures and a loss of sea ice, with a consequent reduction in nesting and breeding grounds, as well as a drop in food availability. "This is very interesting research and it suggests the heat exchanger is an adaptation to allow longer to be spent in the water," says Dr Jonathan Green, lecturer in marine biology at the University of Liverpool. "It is an adaptation which developed to promote foraging in warmer water and by coincidence proved to be helpful in cold waters and air temperatures. The same mechanism is employed in other parts of the penguin body, including the feet, which stops them freezing when they are in contact with ice. 

"Our own research has shown that global warming is a threat. Only two of the 17 species of penguin breed on the Antarctic continent. The others live in the sub-Antarctic and temperature regions in South America, South Africa and Australasia. Our research in Australia has shown that temperature rises can cause problems for the penguins. A danger from global warming is that this overheating may lead them to abandoning breeding attempts, resulting in declining population numbers." 

Huddling: The emperor's other way of warming up
Penguins keep warm on land by huddling.
 
Scientists have found that it is highly effective for keeping warm on land and can generate a tropical environment in one of the coldest environments on earth. 

The emperor penguin breeds during the severe Antarctic winter, and the males have the job of incubation, which involves them being deprived of food for around 65 days. 
 
But successful breeding requires a temperature of around 35C, and so to keep warm, the males huddle.
Researchers from the Scott Institute of Polar Research, who investigated what exactly happens inside huddles for the first time, showed that the birds spend an average of 38 per cent of breeding time huddling, with huddles lasting around 90 minutes. The birds moved around in the huddle so they all had access to the inner warmth. 
 
Temperatures during tight huddling increased from 20C to 37.5C in less than two hours. "This complex social behaviour enables all breeders to get a regular and equal access to an environment which allows them to save energy and successfully incubate their eggs. Huddling behaviour of emperor penguins is a far more complex behaviour than previously described," say the researchers. 

Sunday, February 13, 2011

How Dinosaurs Handed Down Their Fingers to Birds

Wynne Parry  LiveScience Senior Writer

Birds are believed to be descended from dinosaurs, but some significant changes must have happened as they evolved from their ancestors. A new study involving baby chicks may help clear up a mystery of how one of those changes occurred -- how birds got their wing "fingers."
All four-limbed creatures, including dinosaurs, evolved from an ancestor that had five digits at the end of its limbs. These became flippers, wings, hands or paws, and some or all of the digits disappeared altogether in some cases.
Scientists think birds evolved from a group of meat-eating dinosaurs called maniraptors some 150 million years ago, during the Jurassic period. Modern birds have three digits in each of their wings, which means two digits in the forelimbs of these dinosaurs would have had to be lost during evolution.

A question of numbering

But which three digits survived? Paleontologists and developmental biologists have disagreed heartily on this. A proposal made in 1999, called the “frame shift” hypothesis, explained a discrepancy in the evidence, but not everyone accepted it.
The new study, conducted by researchers who transplanted cells from one part of a chick’s body to another, adds to the support for the hypothesis. The results of their study appear today (Feb. 10) in the journal Science.
If you number the digits so that digit 1 corresponds with our thumbs, digit 2 with our index fingers and so on, the fossil record shows that birds' wings evolved using digits 1, 2 and 3 of the dinosaur’s forelimbs.
However, in a bird embryo, the digits arise from the places on the limb bud associated with digits 2, 3 and 4. This conflict supported those who challenged whether birds were directly descended from dinosaurs.
In 1999, Günter Wagner and Jacques Gauthier of Yale University bridged the two factions by proposing that during development, digit 1 actually arose from the second position (where digit 2 should have arisen), and so on -- a frame shift.
"The great thing about the frame shift theory is it makes both things correct," said Ann Burke, an evolutionary morphologist at Wesleyan University in Connecticut, who was not involved in the current study. "Birds are dinosaurs, but developmentally the digits are 2, 3 and 4."

The new evidence

In the new study, Japanese researchers led by Koji Tamura of Tohoku University transplanted certain cells from the feet to the wings and vice versa of developing chicks. These cells are implicated in the growth of digit 4. The researchers found evidence that the last digit of the wing does not correspond to the last digit of the foot. This supports the theory that the wing, unlike the foot, does not have a digit 4, they said.Then the team mapped out digit development using cell-labeling techniques (enabling them to know where a certain cell ended up once it matured). They found that by 3.5 days of embryonic development, a shift occurs, causing cells in the progenitor region for digit 4 to move forward and grow into digit 3. The same shift occurs for the digits that become 1 and 2.
"I cannot tell you ‘why’ we have five digits and chickens have three digits, although I will be able to correctly tell you ‘how’ they have three digits whereas we have five digits," Tamura told LiveScience in an e-mail.
The findings accomplish two things, according to Tim Rowe, a professor of paleontology at the University of Texas at Austin who was not involved in the study.
First, "it pertains directly to this seeming conflict between paleontological records and developmental records. It shows in fact there is no inconsistency," said Rowe.
And second, it provides an excellent example of a shift in which one body part is transformed into another during embryonic development, he said.
"We are discovering part of the Holy Grail, which is the evolution of development, how the development of the limb changed during evolution of birds from their theropod ancestor," Rowe said.
This is not the first research to support the frame shift hypothesis, according to Wagner . "I think there is now enough data that shows that the frame shift actually happened," Wagner told LiveScience. "This is going a step further; it shows us the developmental mechanism."


Persistent skepticism
 
To determine the identity of the last digit in the chicks' "hands," the study used the development of the last digits in a five-digit mouse limb as a guiding model. This leaves Alan Feduccia, an evolutionary biologist at the University of North Carolina at Chapel Hill, skeptical of the results.
Feduccia, who wasn't involved in the study, is an opponent of the predominant scientific view that birds are descended from theropod dinosaurs (which include maniraptors). Rather, he believes birds and theropod dinosaurs share a common, earlier ancestor. This new study gives him no reason to change his mind.
"The experimental results seem to be very equivocal," Feduccia said, "because the bird hand is so highly modified that we don't know that same genetic mechanisms apply to digit identity."
The shift in digits just doesn't make sense, he said. "There is no imaginable selective advantage for such a shift -- in other words, why would it occur?"
But he is in the minority.
Wesleyan’s Burke has another issue with the frame shift theory; she believes renumbering the digits of the growing chicks is potentially misleading.
"The dinosaur ancestry of birds is absolutely sound and so well-supported that nobody disagrees with that, so just trying to change the digit numbers in living birds to conform to fossilized ancestry is unnecessary and eclipses important evolutionary change," she said.

Source

Wednesday, February 9, 2011

Little Blue Penguin Shows Its Colors


>Little blue penguins are the world's smallest penguins, and are found on Australia and New Zealand. While they are not considered endangered, they are losing some habitat due to urban encroachment. Credit: Dreamstime.

Dapper Blue Penguin: Tux Is a Feathery First

By Jennifer Welsh, LiveScience Staff Writer
08 February 2011
If these penguins look blue to you, it's not because they are down in the dumps. They have a special protein structure in their feathers that generates the blue color by reflecting light in a way that has never been seen in feathers before.

Lead author Matthew Shawkey of the University of Akron was surprised to find the new structures, which "shatter current dogma," Shawkey told LiveScience. "We found a previously undescribed way that birds make a non-iridescent blue color in feathers."

Shawkey found the structure in feathers of the blue penguin, a bird commonly found in Australia and New Zealand and also called the little, or fairy, penguin, awkwardly stands about a foot tall (30 cm) and weighs a little more than 2 pounds (about 1 kg). They have the traditional tuxedo look of penguins, though their feathers are a non-iridescent dark blue.

For the last 30 years only two ways of making a non-iridescent blue feathers were known, both which depend on holes in a spongy-like matrix of a protein called beta-keratin. The pores in the matrix trap and reflect light in the blue color range. "When I first looked at them [the feathers] I expected them to be one of these other two mechanisms," Shawkey said to LiveScience.

In the blue penguin feathers, the beta-keratin is aligned into parallel fibers, like a row of hairs. The alignment and size of the fibers scatters the light and reflects those in the blue pigment range. This is the first time this organizational structure has been seen to produce color in feathers.

"The mechanisms that produce structural coloration in animals is so little studied that I am not surprised at all that a new mechanism was found in penguins," Geoffrey Hill at Auburn University in Auburn, Ala., who was not involved in the study. "Shawkey and Prum are like the first Europeans who came ashore in North America and had a vast uncharted realm to explore."

Ancient pigments

The discovery was not only a surprise in itself but an unexpected find to Shawkey, who stumbled upon the odd structure during the course of another project. After some recent work reconstructing the color of ancient dinosaur feathers, Shawkey moved on to analyzing the color of some 35 million-year-old penguin feathers, which required his team to analyze the color-producing pigments and proteins in living penguins.

When his team took a look at what made the blue penguin's feathers blue, he was shocked. "These fibers were unexpected, they look totally different than anything we ever seen before," he told LiveScience.

The team looked at how these filaments scattered light and X-rays to determine what the structures look like and figure out how they were producing the blue color. They saw that the structure was highly organized; It looked a lot different than the spongy, disordered keratin structures that have been observed to create colors in feathers before.

The 160-nanometer keratin filaments lined up in an array that Shawkey describes as "a handful of uncooked spaghetti." They also saw that how the filaments were lined up would create a blue color reflection. Hundreds of the fibers line up side by side in the cells that make up the feather's barbs — the silky fibers that branch off of the quill.

"The significance lies in the realization that there are many ways to use nanostructures to produce blue color," Hill told LiveScience in an e-mail. "The research underscores that we should keep investigating structural coloration in diverse animals to see what other ingenious mechanisms natural selection has produced."

Evolving technologies

Beta-keratin is known to self-assemble fibers and Shawkey said that this parallel arrangement might have evolved from that ability of beta-keratin. If the structure does assemble itself, instead of needing a cellular scaffold, it could be easily manufactured. "There might be some interest in mimicking these for applications from things like cosmetics to fiber-optic cables," Shawkey told LiveScience. "If they are self- assembled it would be interesting because it would be cheap to manufacture them."

Shawkey also wonders if this organization somehow gives the penguin feathers special benefits, like additional strength or rigidity to withstand flying through the water, which is 1,000 times more viscous than the air birds normally fly through.

While this is the first time this sort of structural formation of blue color has been seen in feathers, a similar method of color production has been seen in blue skin of birds, though in that case the fibers are made up of collagen.

"Both beta-keratin and collagen have an innate tendency to self-assemble into fibers, so it makes sense that you would find these nanofibers made from both beta-keratin and collagen." The two structures seem to be an example of convergent evolution, when two structures evolve separately but use the same mechanism, he said.

Source

Tuesday, February 1, 2011

Paleontologist after more evidence that relatives of modern birds co-existed with dinosaurs

A woman works on a rock.
Photo Credit: N. Adam Smith
Julia Clarke exposes a wing feature on a fossilized penguin specimen recovered from Peru. She and colleagues found evidence from fossils collected in Antarctica in the 1990s that at least one species related to modern birds lived at the same time as dinosaurs. She and a science team are headed to the Antarctic Peninsula in February 2011 in hopes of finding more fossils.

Winging it

The theory that close relatives of modern birds once co-existed with non-avian dinosaurs before a mass extinction 65 million years ago had trouble flying with many paleontologists until about five years ago.

That was when a team of scientists announced that new data from fossils discovered in Antarctica in the 1990s by Argentine researchers offered evidence that at least one species related to modern birds shared the same space and time with dinosaurs. [See previous article: Antarctic bird nest?]

Julia Clarke External Non-U.S. government site was the lead author of that Nature paper, with the bold title “First definitive fossil evidence for the extant avian radiation in the Cretaceous.” Now Clarke, an associate professor of paleontology at the Jackson School of Geosciences at the University of Texas in Austin External Non-U.S. government site, hopes to get her hands on additional material from Antarctica that will fill in more of the story about the early spread of all living birds.

Toward that purpose she’ll join a team of paleontologists headed to a group of islands off the Antarctic Peninsula early next year led by Ross MacPhee External Non-U.S. government site, with the American Museum of Natural History in New York External Non-U.S. government site. [See related article: Reverse course.]

The fossil hunters include dinosaur and mammal experts. “It’s a group of vertebrate paleontologists that want to ask questions that only Antarctic fossils can answer,” Clarke said.

It will be Clarke’s first trip to the Antarctic, though her fieldwork has often taken her to the Southern Hemisphere and locations from Argentina to Peru to New Zealand. Her work in South America, in particular, has shed new light on penguin evolution. [See related article: Penguins of a feather.]

But it’s in Antarctica where she believes more evidence is waiting to be found to show that the ancestors of modern birds lived more than 65 million years ago. Most scientists believe an asteroid hit the Earth and caused a cataclysmic extinction. Non-avian dinosaurs disappeared, along with an estimated three-quarters of all species.

“For parts of and close relatives of the crown clade — relatives of living bird lineages — Antarctica is the place to go. And Vega, specifically, is the place to go — globally,” Clarke said.

Vega Island, a small island off the Antarctic Peninsula, has proven to be relatively rich with fossils from the Late Cretaceous, about 80 million to 65 million years ago. The asteroid impact, which marks the so-called K-T Boundary, is estimated to have occurred around 64 million years ago.

It was on Vega where the Argentine scientists found the specimen that Clarke and colleagues would later call Vegavis iaai, which falls within the order Anseriformes, which includes ducks, geese and swans.

Bird bones stuck in a rock.
Photo Courtesy: Julia Clarke

Vegavis iaai concretion, left, and the CT scan of the rock and bird fossils.
The rock specimen from Vega contained avian vertebrae and pelvic bones among other bits of skeleton. Clarke used a high-resolution X-ray CT scanner to see the fossils without breaking the rock and possibly damaging the material.
In spite of the Vega evidence, there is still contention among paleontologists of what lineages are present in the Cretaceous prior to the K-T boundary, according to Clarke.

In 2008, she and co-principal investigator Judd Case at Eastern Washington University External Non-U.S. government site received a Small Grant for Exploratory Research (SGER) from the National Science Foundation (NSF) External U.S. government site to pull together data and experts on Antarctic fossils from the last 20 years to see if more evidence existed to support the theory of a robust modern radiation from Antarctica.

It’s a good start, Clarke said, but added, “What we really need are new specimens because some of the important material that Case and the Argentine teams collected during their field seasons can just hint at the bird species present.

“It is just the tantalizing beginning of what we need to know; we need to get better specimens. … There’s arguably no better material in the world than what’s come out of Vega so far. There’s a lot more work that can be done there.”

Hence the expedition to the islands of the Antarctic Peninsula, which requires a trip aboard a research vessel toward the end of the Southern Hemisphere summer in February. The scientists will make day trips to the islands from small inflatable boats, as well as work out of field camps on the islands for days at a time.
The researchers can expect long hours in cold conditions, sifting through rocks and dirt for the small fragments that might offer further clues about the ancient history of birds, mammals and dinosaurs.

For her part, Clarke is hesitant to state that Antarctica was ground zero for modern bird evolution — but she also doesn’t dismiss the possibility. “If we can increase our sampling globally, we can get a better sense of what role Antarctica played in the diversification of birds. We don’t know that it’s the area of origin,” she said.

“Finding bird fossils is always a rare occurrence, but based on what we specimens have been collected from Antarctica to date, work in this region has a high probability of success. In terms of spinning a roulette wheel of fossil discovery, if you will, I think it’s weighted in our favor in this case. I think we’re going to find more complete material if we can spend the time at the sites.”

NSF-funded research in this story: Julia Clarke, University of Texas at Austin, Award Nos. 0927341, 0408308, 0731404 External U.S. government site (with Judd Case, Eastern Washington University). 


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