Friday, January 25, 2013

New Dinosaur Fossil Challenges Bird Evolution Theory

Reconstruction of Eosinopteryx. (Credit: Royal Belgian Institute of Natural Sciences) 

Jan. 24, 2013 — The discovery of a new bird-like dinosaur from the Jurassic period challenges widely accepted theories on the origin of flight.

Co-authored by Dr Gareth Dyke, Senior Lecturer in Vertebrate Palaeontology at the University of Southampton, the paper describes a new feathered dinosaur about 30 cm in length which pre-dates bird-like dinosaurs that birds were long thought to have evolved from.
Over many years, it has become accepted among palaeontologists that birds evolved from a group of dinosaurs called theropods from the Early Cretaceous period of Earth's history, around 120-130 million years ago. Recent discoveries of feathered dinosaurs from the older Middle-Late Jurassic period have reinforced this theory.
The new 'bird-dinosaur' Eosinopteryx described in Nature Communications this week provides additional evidence to this effect.
"This discovery sheds further doubt on the theory that the famous fossil Archaeopteryx -- or "first bird" as it is sometimes referred to -- was pivotal in the evolution of modern birds," says Dr Dyke, who is based at the National Oceanography Centre, Southampton.

"Our findings suggest that the origin of flight was much more complex than previously thought."
The fossilised remains found in north-eastern China indicate that, while feathered, this was a flightless dinosaur, because of its small wingspan and a bone structure that would have restricted its ability to flap its wings.

The dinosaur also had toes suited to walking along the ground and fewer feathers on its tail and lower legs, which would have made it easier to run.
Dr Gareth Dyke is also Programme Leader for a new one-year MRes in Vertebrate Palaeontology, which offers potential students the chance to study the evolution and anatomy of vertebrates, in order to inform and increase our understanding of the workings of modern day creatures.

Dr Dyke's co-authors are Pascal Godefroit of the Royal Belgian Institute of Natural Sciences, Helena Demuynck of Earth System Science Vrije Universiteit Brussel, Dongyu Hu of Paleontological Institute Shenyang Normal University China and Key Laboratory of Vegetation Ecology Northeast Normal University China, François Escuillié of Eldonia France and Philippe Claeys of Jilin University Geological Museum China.

Story Source:
The above story is reprinted from materials provided by University of Southampton.
Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Journal Reference:
  1. Pascal Godefroit, Helena Demuynck, Gareth Dyke, Dongyu Hu, François Escuillié, Philippe Claeys. Reduced plumage and flight ability of a new Jurassic paravian theropod from China. Nature Communications, 2013; 4: 1394 DOI: 10.1038/ncomms2389

University of Southampton (2013, January 24). New dinosaur fossil challenges bird evolution theory. ScienceDaily. Retrieved January 25, 2013, from

Wednesday, January 23, 2013

Sex of Early Birds Suggests Dinosaur Reproductive Style: New Way to Identify Gender of Ancient Avian Species

 Reconstruction of Confuciusornis sanctus. (Credit: Stephanie Abramowicz, NHM Dinosaur Institute)

Jan. 22, 2013 — In a paper published in Nature Communications on January 22, 2013, a team of paleontologists including Dr. Luis Chiappe, Director of the Natural History Museum of Los Angeles County's (NHM) Dinosaur Institute, has discovered a way to determine the sex of a prehistoric bird species.

Confuciusornis sanctus, a 125-million-year-old Mesozoic bird, had remarkable differences in plumage -- some had long, almost body length ornamental tail feathers, others had none -- features that have been interpreted as the earliest example of avian courtship. However, the idea that male Confuciusornis birds had ornamental plumage, and females did not, has not been proven until now. Chiappe and the team studied hundreds of Confuciusornis fossils unearthed from rocks deposited at the bottom of ancient lakes in what is today northeastern China and found undisputed evidence of the gender difference: medullary bone. 
Chiappe conducted the study with Anusuya Chinsamy of the Department of Biological Sciences, University of Cape Town, South Africa; Jesús Marugán-Lobón of Madrid's Universidad Autonóma, Cantoblanco; Gao Chunling and Zhang Fengjiao of the Dalian Natural History Museum in China.
"Our discovery provides the first case of sex identification in an ancient bird, an animal closely related to dinosaurs, such as the famous Velociraptor," said Chiappe. "When people visit dinosaur exhibits, they often want to know if the skeletons are male or female. We have nicknames like Thomas and Sue, but of all the thousands of skeletons of dinosaurs or early birds found around the world, only the sex of a few has been determined."

According to Chinsamy, the bone histologist on the team, "Just like modern hens, female Confuciusornis birds that lived 125 million years ago deposited this special bone inside their long bones, and then used it to make the calcium-rich eggshells." Finding such tissue -- present during a short period of time in reproductively active females -- in a specimen that lacked long feathers proved that those birds without ornamental plumage are females.

"This now permits us to assess gender differences in growth and development of this Mesozoic bird," she said.

But while this discovery offers evidence that both early and modern female avian species were essentially using the same physiological strategy to reproduce, it also spotlights an important difference in when they sexually matured.

"In human terms, knowing the sex of these specimens sheds light on when these early birds begin puberty," said Chiappe, "Now we know that early birds began reproducing way before they were full grown, a pattern that contrasts with what we know of living birds, which typically begin reproducing after they reach full body size." In that way, ancient birds produced offspring like dinosaurs, which also began to reproduce before they were fully grown.

The specimens, housed at the Dalian Natural History Museum in northeastern China, had been excavated from rocks formed at the bottom of ancient lakes in a forested environment surrounded by volcanoes. Ancient catastrophes, presumably related to volcanic eruptions, killed large numbers of birds and other animals, whose bodies were buried deep in the lake mud that helped minimize decay and preserving the organs, skeletons, and plumage. "This discovery is part of the big picture of understanding the early evolution of birds,'' Chiappe said, "and how living birds became what they are."

Story Source:
The above story is reprinted from materials provided by Natural History Museum of Los Angeles County, via EurekAlert!, a service of AAAS.
Note: Materials may be edited for content and length. For further information, please contact the source cited above.

Journal Reference:
  1. Anusuya Chinsamy, Luis M. Chiappe, Jesús Marugán-Lobón, Gao Chunling, Zhang Fengjiao. Gender identification of the Mesozoic bird Confuciusornis sanctus. Nature Communications, 2013; 4: 1381 DOI: 10.1038/ncomms2377

Natural History Museum of Los Angeles County (2013, January 22). Sex of early birds suggests dinosaur reproductive style: New way to identify gender of ancient avian species. ScienceDaily. Retrieved January 23, 2013, from­ /releases/2013/01/130122111654.htm

Tuesday, January 22, 2013

'Critter Cam' Reveals Secrets of Penguin Hunts

Date: 21 January 2013

                           "A colony of Adélie penguins on the West Antarctic Peninsula.
                                                              CREDIT: Sue & Wayne Trivelpiece 


A new "critter cam" has captured the speedy dives of Antarctic penguins as they hunt for prey.

The videos, captured by cameras attached to the birds, reveal that when going for fish, penguins use shallow dives, but may plunge deep into the frigid Antarctic waters to capture their favorite food, tiny shrimplike crustaceans called krill.

While studies of penguins' stomach contents have revealed fish and krill, exactly how the best-dressed animals capture them has remained a mystery.

Yuuki Watanabe and Akinori Takahashi of the National Institute of Polar Research in Tokyo wanted to understand exactly how penguins hunt. To do so, they attached critter cams to 11 Adélie penguins that live in Lützow-Holm Bay, Antarctica. The critter cams recorded about 85 minutes of activity from each animal as they held their breath and dived for prey. The findings were published today (Jan. 21) in the journal Proceedings of the National Academy of Sciences.

 The team found that the penguins stuck to shallower waters to hunt a small, silvery fish called Pagothenia borchgrevinki, but made both shallow and deep dives for krill. That makes sense because "krill form swarms in the water column and appear in a highly variable density," the authors wrote in the paper.

While dives for fish produced a steady supply of food, dives for krill were more unreliable. "This difference indicates that the success of penguins feeding on krill during a foraging trip depends on a small number of very successful dives, rather than a number of typical dives."

All in all, the penguins were impressive hunters, with no divers coming up empty-beaked. During about 88 minutes of diving (many individual dives), the Antarctic birds devoured 244 krill and 33 Arctic fish. The cameras also revealed that the penguins turned their heads quickly to engulf prey.
"Our movies showed that the foraging behavior of Adélie penguins is remarkably fast and efficient," the researchers wrote.

The findings could help explain why the population of a penguin colony of Adélies doesn't seem to change with the amount of time the birds hunt.


Wednesday, January 9, 2013

Study charts DNA mutations



CURIOUS SUBJECT: An Adelie penguin in the Ross Sea area in Antarctica.
A scientist who used to study crime scenes for a living is now using ancient penguin DNA from Antarctica to uncover the past and make predictions for the future.

The three-year project is an extension of a previous study published by former forensic scientist and senior lecturer at the University of Auckland Dr Craig Millar and his collaborators about a decade ago.

The previous study used DNA from different time periods to measure the rate of evolutionary change in Adelie penguins, and discovered that it was five to seven times faster than previously thought.
Dr Millar said it measured a small but important genome section that was used extensively in forensics, but genome-sequencing technology had improved significantly since then.

The process was now much faster and radically cheaper, allowing his research team to sequence entire genomes found in well-preserved Adelie penguin bones as well as living birds. "The technology has just revolutionised the sequencing process. The cost of it is plummeting," Dr Millar said.

The new technology would enable the research team to examine what evolutionary changes had occurred in Adelie penguins since the peak of the last glacial period, between 18,000 and 25,000 years ago.

Antarctica had warmed about 10 to 12 degrees Celsius since deglaciation started about 12,000 years ago, and the team wanted to discover what, if any, evolutionary response that had prompted. "It allows us to look at the past, but it also allows us to look forward and predict what might happen in the future. We are probably going to face another temperature change. It would be genetically very interesting to see how genes respond."

The sequencing will be done this year, with the final stages completed in China, but the scientists' data collection starts well before that - on their hands and knees in Antarctica.

Dr Millar and his team are in the Ross Sea region this month, surveying various sites for signs of ancient or relict Adelie penguin colonies, with logistical support from Antarctica New Zealand.
When they see something that looks promising, from a helicopter or while on the ground, they stop and start their "treasure hunting" or "penguin archaeology."

They find pebbles from old nests, guano, eggshells, feathers, bones and sometimes whole chicks, well preserved in the coldest and driest place on Earth.

Yvette Wharton, also of the University of Auckland, said it was "exactly like an archeological dig - you do it layer by layer. It's like uncovering treasure."

The Kiwi scientists' colleagues include Italian geomorphologists Dr Carlo Baroni and his partner, Dr Maria Cristina Salvatore, of the University of Pisa.

Dr Baroni is collecting ancient penguin samples from relict colonies and using dating techniques to reconstruct the glaciation history of different regions, as Adelie penguins nest only in ice-free areas during summer.

Ms Wharton said Adelie penguins were interesting to study when it came to climate change. Although many species responded to temperature increases by migrating, Adelie penguins had "nowhere to go."


First Contact: Emperor penguin colony receives first ever human visitors

January 8, 2013
First Contact: Emperor penguin colony receives first ever human visitors

Credit: International Polar Foundation
(—Three team members from Belgium's Princess Elisabeth Antarctica polar research station are the first humans to have ever visited and photographed a newly-discovered 9,000-strong colony of emperor penguins on Antarctica's Princess Ragnhild Coast.
Researchers from the and the US National Environment Research Council first discovered the colony of 1m-tall emperor using satellite imagery, and published the location in a 2009 paper "Penguins from space: faecal reveal the location of colonies". However, the colony's existence was unconfirmed until expedition leader Alain Hubert and station, chief mechanic Kristof Soete from Belgium and Swiss mountain guide Raphael Richard travelled to the colony in early December 2012.

"Since we started operating along Princess Ragnhild Coast we have encountered so many emperors penguins that I was convinced that a colony must be installed somewhere in the east", said Hubert.
"I knew from last year's satellite study that there could potentially be an emperor colony east of Derwael rise. Because we were operating not far from this the satellite location, I decided to force the way and try to access to this remote and unknown place. The surprise was even more than all I could have expected or dreamed about: I realised while counting the penguins that this was a very populated colony. "

"It was almost midnight when we succeeded in finding a way down to the ice through crevasses and approached the first of five groups of more than a thousand individuals, three quarters of which were chicks. This was unforgettable moment!"

Hubert and Soete were part of a team supporting scientific research on the Derwael Ice Rise, some 50km from the , and 250km from Princess Elisabeth Antarctica. The projects carried out at the site included IceCon, which aims to gain a better understanding of the rate of the loss of ice – now and in the past - from the in the Dronning Maud Land area. The Be:Wise project aims to improve understanding of ice-shelf flow dynamics by focusing on the buttressing role of ice rises and pinning points – small offshore mountains which support Antarctic ice shelves from underneath.

Princess Elisabeth Antarctica is the world's first zero emission polar research station, and is operated by the International Polar Foundation, in partnership with the Belgian Polar Secretariat. Princess Elisabeth Antarctica's design and construction seamlessly integrates passive building technologies, renewable wind and solar energy, water treatment facilities, continuously monitored power demand and a smart grid for maximising energy efficiency. Located in East Antarctica's Sør Rondane Mountains, Princess Elisabeth Antarctica welcomes scientists from around the world to conduct research in this little-studied and pristine environment.

More information: The coordinates for the Ragnhild Coast colony are 27.24713, −69.96615
Paper: Penguins from space: faecal stains reveal the location of emperor penguin colonies - Peter T. Fretwell and Philip N. Trathan


Monday, January 7, 2013

Weird! This Odd, Ancient Bird Had Sharp Teeth

Date: 07 January  2013
toothed-bird illustration
A fossil skeleton of a toothed bird has been unearthed in China. The Cretaceous Era bird had specialized teeth for cracking open hard foods such as insects or snails.
CREDIT: Stephanie Abramowicz

The fossil skeleton of a bird with strange teeth that lived 125 million years ago has been discovered in China. The bird had bizarre ridges on its teeth that may have enabled it to crack open hard-shelled insects and snails, the researchers said.

The unusual fossil, described in the January issue of the Journal of Vertebrate Paleontology, was so well preserved that some of its stomach contents were still present. The new find sheds light on the range of foods Earth's earliest birds ate during the dinosaur era.

"The teeth are weird and there are some stomach contents, which is unusual," said paleontologist Gareth Dyke, of the University of South Hampton in the U.K., who was not involved in the study. "It's more evidence for the uniqueness and range of ecological specialization that are seen in these particular Mesozoic birds."

Teeming with life

The new species' specimen was unearthed in the Liaoning province in China, where many fossils from the Cretaceous Period (the period from 145 million to 65 million years ago that was the end of the Mesozoic Era) have been found over the last 15 years, said study author Luis Chiappe, director of the Dinosaur Institute at the Natural History Museum of Los Angeles. The primeval forest was teeming with ancient life, from pterodactyls and dinosaurs such as the microraptor to primitive lizards and various trees. The skies were also filled with birds, he said.

The well preserved Sulcavis geeorum teeth still had enamel on them.
CREDIT: Stephanie Abramowicz

"This was clearly a hotspot of ancient bird biodiversity," Chiappe told LiveScience.
Toothy bird

The newly discovered bird, a robin-size creature called Sulcavis geeorum, lived between 121 million and 125 million years ago. Sulcavis geeorum belonged to a class of extinct toothed birds called Enantiornithines, which were the most numerous birds during the age of dinosaurs. The diminutive creature looked somewhat similar to modern-day songbirds, with a key difference: the bird had some very strange teeth.

The teeth of this tiny flier had sharp, pointy crowns. In addition, the fossil found by Chiappe's team had preserved tooth enamel that formed serrated ridges. Those serrated ridges probably enabled the birds to crack open the hard exoskeletons of insects, crabs or snails, Chiappe said.

fossil-bird skeleton
The fossil was so well-preserved that some of the stomach contents were still present
CREDIT: Stephanie Abramowicz

The strange teeth may shed light on a prehistoric mystery of sorts: No one knows exactly why early birds had teeth. It's also unclear why they have lost their teeth at least four times since they first emerged in the fossil record. In fact, modern-day birds still have genes for teeth, but the genes are turned off, Chiappe said.

"The traditional view is that teeth are heavy, and the birds evolved beaks as a way of making their bodies lighter. These teeth are pretty small and it's hard to imagine that they had such a huge impact on the weight of the animal," he said.


Penguins' Private Lives Recorded in Antarctica

Date: 06 January 2013
Adélie penguins
A colony of Adélie penguins on the West Antarctic Peninsula.
CREDIT: Sue & Wayne Trivelpiece

— Suppose someone monitors your whole life, from the moment you were born through childhood, puberty, adolescence and your midlife crisis, all the way to your ultimate death — recording what you eat, where you go, who you make love to, when you raise children and how your body ages. Pretty scary, right?
But that's exactly what biologist David Ainley is doing. Not with humans, but with Adélie penguins in Antarctica. If he could put TV cameras in the birds' master bedrooms, he wouldn't hesitate.

No detail too private

For 17 years now, Ainley has studied three penguin colonies in and around McMurdo Sound, located at the southern extent of the Ross Sea. "It's rare in science to collect data throughout the whole age structure of a population," Ainley told LiveScience, noting Adélie penguins live, on average, about 20 years. Some of the sedate, elderly colony members were just "screaming" newborn chicks when he first arrived here in 1996.

Don't ask these guys to tap dance. Adelie penguins in Antarctica.
CREDIT: Dr. Robert Ricker, NOAA/NOS/ORR

Back then, the three colonies were growing rapidly, at a rate of about 10 percent per year. "My original goal was to find out what caused this increase, and why the smaller colonies grew even faster than the larger ones," said Ainley, who is a biologist at H.T. Harvey & Associates, an ecological consultancy in San Jose, Calif.

Surprisingly, the baby boom turned out to be a side effect of the Antarctic ozone hole (an opening in the protective atmospheric layer), which reached huge dimensions in the 1990s. "A larger ozone hole means a cooler stratosphere, a more powerful polar vortex and, as a result of stronger winds, more open water in the immediate neighborhood of the colonies," he said. The penguins need the open water for finding their favorite foods — krill and fish.

With funding from the U.S. Antarctic Program, through the National Science Foundation, Ainley has discovered a lack of competition for scarce food resources is what drives the smaller colonies to grow faster than larger ones. Also, predator leopard seals, which aren't very efficient hunters, are more interested in the bigger colonies, where they have a better chance to catch their nourishing penguin snack.

Along the way, penguin privacy has gone out the window: To keep track of a representative selection of individual penguins, Ainley has banded them on one of their flippers, making it easy to identify each from afar through binoculars. [Image Gallery: Private Sex Lives of Penguins]

Moreover, at the exit of the colonies, Ainley has mounted electronic weigh bridges, over which the penguins have to pass when they go foraging in the open sea, and again when they return to feed their newborn chicks from their own stomachs. Radio-frequency chips identify the penguins, and the automatic measurements provide a detailed record of their foraging and feeding behaviors during the austral summer season.

An icy obstacle

All was going well with Ainley's research. But in March 2000, catastrophe struck. A huge part of the Ross Ice Shelf broke loose. The iceberg, nearly the size of the state of Connecticut, blocked access to the open waters of the Ross Sea, effectively cutting off the penguins' preferred route to their winter habitat, farther away from the pole. To reach these slightly warmer and less gloomy regions with their fish and krill in tow, the poor birds now had to take a 50-mile (80 kilometers) detour. Eventually, the iceberg would remain stuck for a period of five years, and the penguin colonies diminished markedly. [Album: Stunning Photos of Antarctic Ice]

"At first, I was very disappointed," said Ainley, as it looked as if the iceberg had wrecked his research program. "But then it turned out that there was a lot of new information to gain from the whole episode." In particular, Ainley discovered many penguins from the small colony at Cape Royds did not return home at all in the summer season, but started a new life at one of the other two Adélie colonies at Ross Island — at Cape Crozier and Cape Bird.

This was completely unexpected, said Ainley. "The scientific gospel was that penguins live in the same colony for their entire life, and that they never migrate elsewhere. But the gospel was written by people who had never witnessed an iceberg event like this one."

Contemplating the universe

By now, everything is pretty much back to normal again. Together with his colleague Jean Pennycook, Ainley started his 17th field expedition in early December. Every other day at Cape Royds, he walks through the penguin colony, armed with a pair of binoculars, keeping track of what the birds are doing. "There's not very much to do, really,” he said. “Actually, I spend most of my time at my laptop." Research results, as well as daily pictures from breeding nests, are published at a special website,, partly for educational reasons.

The small colony at Cape Royds has a population of about 2,000 penguin pairs, as opposed to Cape Bird, with some 50,000 pairs, and Cape Crozier, the biggest colony in the world, with a staggering 280,000 pairs. "At the other colonies, there's more than enough work to keep two people busy for seven days a week," he said.

But despite the cold, Ainley doesn't seem to mind the relative lack of work. Pointing at the male penguins that are solemnly breeding two fresh-laid eggs each, he notes: "They're just sitting there, contemplating the universe."

To many researchers in Antarctica, the combination of utter remoteness and overwhelming natural beauty is the main atttraction of the frozen continent. In fact, Ainley admits he choose penguin research for his doctoral work just to get a chance to go to Antarctica. "I just had to go there," he said. "I could've chosen geology instead, since I also majored in that discipline."

Then again, monitoring the full life cycle of a mountain or a glacier, from birth to death, is a bit beyond human scope. In the case of the Adélie penguins, Ainley almost accomplished this feat. "I'll return two more times on my current grant," he said. "If I'm creative enough to come up with a new research project, I may receive another five-year grant."

The penguins aren't likely to mind. Who knows, they might start to miss their human friend if he weren't to show up anymore.

Dutch freelance science writer Govert Schilling visited McMurdo Station and the Amundsen-Scott South Pole Station in early December as a selected member of the National Science Foundation's Antarctic media visit program.


Saturday, January 5, 2013

Dinosaurs Shook Tail Feathers To Lure Mates, Oviraptor Fossils Suggest


New research suggests male oviraptor dinosaurs would shake their tail feathers to woo potential female mates (reconstruction of such dino-wooing shown here). Oviraptor (here, “Ingenia” yanshini) courtship display. Credit: Sydney Mohr, University of Alberta
By: Charles Choi, LiveScience Contributor
Published: 01/04/2013  on LiveScience

Feathered dinosaurs might have used muscular tails to shake tail feathers and lure the opposite sex, researchers say.

Scientists analyzed 75-million-year-old fossils of feathered, two-legged dinosaurs known as oviraptors retrieved during expeditions to the Gobi Desert in Mongolia. Although oviraptors were members of the meat-eating theropods, making them relatives of such fearsome predators as T. rex and Velociraptor, most oviraptors had beaks that lacked teeth.
Digital models of the tailbones and musculature of an oviraptor. 

"There are good reasons to think they had gone vegetarian," researcher Scott Persons, a vertebrate paleontologist at the University of Alberta in Canada, told LiveScience. "They were odd ducks, strange dinosaurs," said Persons, who presented the study results at the Society for Vertebrate Paleontology's annual meeting in November, but only this week were they published in a scientific journal.

Past research had revealed oviraptors often had eye-catching bone crests on their heads. "Now we know there was something funny going on at the other end, too," Persons said.

Oviraptor tails were short, but were made of many tailbones, with many points between these vertebrae where they could flex. Persons and his colleagues found oviraptor tailbones also had many projections onto which muscles could attach. Computer models estimating the size of these muscles based on oviraptor skeletons suggest these muscles were quite large. [Paleo-Art: Stunning Illustrations of Dinosaurs]

"Their tails were not only very, very flexible, but quite muscular," Persons said. "They could not only move them sinuously to strike a pose, but also hold it to do a muscular dance with the tail."
A series of five fused bones at the end of the tail of the oviraptor Nomingia.

Unusually, at the very end of the tail, "in some oviraptors, the last few vertebrae were actually fused together to become one solid, ridged, bladelike structure," Persons said. "The only other kind of animal where you see that are modern-day birds, where it's called a pygostyle, which serves as an anchor point for a big fan of tail feathers."

Modern-day birds use pygostyles to help them fly, "but oviraptors were not flying animals — they had feathers, but they didn't have big broad wings," Persons said. "What else are pygostyles used for? Peacocks and turkeys use their tail feathers for courtship displays."

Past research has suggested that dinosaurs may have first evolved feathers for show, not flight. Persons and his colleagues found that at least four known oviraptor species separated by 45 million years had pygostyles.

"I think like peacocks, oviraptors were strutting their stuff by shaking their tail feathers to show off," Persons said. "Between the crested head and feathered-tail shaking, oviraptors had a propensity for visual exhibitionism."

Although feathers on dinosaur forearms might have served as stabilizers that helped them steer, that may not have been the case for any tail plumes. "Flightless birds such as ostriches and emus don't have big tail-feather fans, and birds that do have big tail-feather fans such as peacocks and turkeys don't try to use them to run at all, but just keep them tucked in except when fanned out for display."
In the future, Persons and his colleagues want to see if such tails were typically found in one sex or the other. "Maybe they were larger in males, as we see in modern-day birds," Persons said. "The problem there is that the tip of the tail is one of the rarest parts of a fossil skeleton to find, so it might be hard to discover evidence of these sexual differences."

Persons and colleagues Philip Currie and Mark Norell detailed their findings in the Jan. 4 issue of the journal Acta Palaeontologica Polonica.



Tuesday, January 1, 2013

Penguins Punctuate 2012 Papers for PLOS ONE

Today is the last day of 2012. As you put on your formal wear and get ready to ring in the new year, why not reflect on the animal that’s always in style: the penguin! This year, PLOS ONE published an exciting array of penguin research. Here is a snippet of those penguin papers that attracted media attention and some that flew (or swam) under the radar.

Affectionately dubbed the “penguins from space” paper (after the Scientific American article of the same name), “An Emperor Penguin Population Estimate: The First Global, Synoptic Survey of a Species from Space” made the headlines in 2012. In the study, researchers used satellite imagery to count the number of emperor penguin colonies on the coasts of Antarctica. They developed techniques for differentiating between shadows in the snow, penguin guano, and the penguins themselves. In total, about 238,000 breeding pairs were identified. According to lead author Peter Fretwell, about 595,000 individual emperor penguins were counted in this first-ever satellite survey. Read more about this study at the BBC and National Geographic.

Have you ever wondered just what penguins do with their time? Our next study, entitled “Activity Time Budget during Foraging Trips of Emperor Penguins”, may help to shed some light on a day in the life of a penguin. As the title suggests, researchers tracked and observed penguins on foraging trips in the water and on sea ice. They noted that penguins spent about 70% of their time in the water, diving to depths of over 5 meters. When outside of the water, penguins spent a majority of the time resting. The researchers suggest that resting on sea ice may provide shelter from predators such as leopard seals. For more on this study, check out this video from the supporting information, or visit NBC and The Telegraph.

We now travel from Antarctica to Argentina in search of Magellanic penguins. In “How Much is Too Much? Assessment of Prey Consumption by Magellanic Penguins in Patagonian Colonies”, researchers calculated rates of prey consumption by analyzing the number of wiggles penguins made while diving. Why count wiggles? According to researchers, Magellanic penguins wiggle – that is, undulate up and down – in pursuit of prey. When penguins wiggle during their dive, it is very likely that they have caught their prey.

This evening as you gather with your loved ones to watch the fireworks, you may wonder how to keep warm in the December chill. Do what penguins do and huddle! In the aptly named “Modeling Huddling Penguins”, researchers developed a mathematical model to study the shape and movement of huddling penguins in extreme cold. The researchers simulated a group of huddling penguins and determined wind flow (refer to the image on the left, which is Fig. 1 from the study). They then identified which penguin would be the coldest and moved that penguin downwind; the scenario was repeated under different wind patterns. The researchers found that even if individual penguins work to conserve individual body heat the group as a whole can distribute an even heat loss.
Have a happy new year! We will see you all in 2013.

Fretwell PT, LaRue MA, Morin P, Kooyman GL, Wienecke B, et al. (2012) An Emperor Penguin Population Estimate: The First Global, Synoptic Survey of a Species from Space. PLoS ONE 7(4): e33751. doi:10.1371/journal.pone.0033751
Watanabe S, Sato K, Ponganis PJ (2012) Activity Time Budget during Foraging Trips of Emperor Penguins. PLoS ONE 7(11): e50357. doi:10.1371/journal.pone.0050357
Sala JE, Wilson RP, Quintana F (2012) How Much Is Too Much? Assessment of Prey Consumption by Magellanic Penguins in Patagonian Colonies. PLoS ONE 7(12): e51487. doi:10.1371/journal.pone.0051487
Waters A, Blanchette F, Kim AD (2012) Modeling Huddling Penguins. PLoS ONE 7(11): e50277. doi:10.1371/journal.pone.0050277

Image: Emperor penguins by lin_padgham