Did All Dinosaurs Have Feathers?

Posted by Robalini on May 10, 2012
http://www.disinfo.com/2012/05/did-all-dinosaurs-have-feathers

I remember reading long ago an article about how man's own psychological and sociological biases can shape how they view scientific phenomenon.   (Sadly, as this was in the pre-Internet days, I can't locate it anywhere on the Web, so forgive me if the details are vague or off a bit.)  Perhaps the best example: when the biological process of impregnation is usually presented, the model is a valiant army of noble sperm battling waves of defenders to the egg as it lays helpless from the attack without the surrounding protections.

This image evokes the idealized fantasies of the Age of Chivalry, turning the act of conception into a battle between knights and warriors over a chaste and passive queen.  (Talk about a Holy Grail.)  It also squares with the gender roles that dominate society, that of the male aggressor and the female as his prey.

It is also, biologically speaking, completely wrong.  Or at least that is what many biologists argue after looking at the evidence.  The conclusion of these biologists: the more accurate model is of an egg, eager to become fertilized, utilizing all its energies to attract and capture the sperm, which would otherwise wander cluelessly and aimlessly to their pointless self-destruction.  And even then, with the millions of sperm released in each ejaculation, the egg is lucky to acquire even one lucky duck in the batch of losers.  Suddenly, conception looks less like a Camelot romance and more like a Judd Apatow comedy.

I don't pretend to be an expert in biology, so I don't have a side in this debate if in fact any debate still exists.  What I do understand is human psychology, and thus I do understand that our own biases can create a paradigm that frames our vision of reality, a paradigm that can trump the evidence itself

With this as a backdrop, it becomes quite quite understandable that when dinosaur bones were first discovered, it would immediately evoke images of lizards.  The creatures revealed by the remains were quite large and thus intimidating, and lizards are quite intimidating as well.  (That the dinosaur could evoke mythological visions of dragons certainly didn't hurt either.)  It is quite understandable looking at their skeletons to immediately equate them with giant reptiles, covered with scaly hides.

Slowly, however, a dissenting view of the dinosaur has developed and evolved, a scientific argument based on observation.  The dinosaur, these intellectual renegades have argued, have less in common biologically with reptiles and more in common with birds, which are direct descendants of the dinosaur.  Given that lineage, it would be more likely that dinosaurs would be covered with feathers.

As evidence has slowly been uncovered of dinosaurs that did indeed have feathers, what was once dismissed without comment has been included in the officially sanctioned view of reality.  Yes, some dinosaurs did have feathers, at least the smaller ones.  Still, as the creatures got larger, the lower the percentage of the creatures that would have feathers.  Thus, the establishment view of prehistoric reality could continue with only minor modifications.

This vision has taken a major blow recently with the discovery of Yutyrannus huali, a name that translates into "beautiful feathered tyrant."  As MSNBC reports: "A team of Chinese and Canadian scientists analyzed three well-preserved fossil skeletons — an adult and two juveniles — recovered from a quarry in China's Liaoning Province by a private fossil dealer. Most striking were remains of downlike feathers on the neck and arm. Though coverage was patchy, scientists suspected the species had feathers over much of its body."

Granted, Yuty-hu wasn't quite as big as T. rex, but it was big enough in its own right, 30 feet long and weighing over a ton.  So the obvious question that MSNBC asks: "If a T. rex relative had feathers, why not T. rex?"  As Luis Chiappe, director of the Dinosaur Institute at the Natural History Museum of Los Angeles County summarized: "People need to start changing their image of T. rex."

But perhaps this is merely the tip of the iceberg.  Rather than ask if T. rex had feathers, shouldn't it be asked if ALL dinosaurs had feathers?  Granted, perhaps this is an assertion that is absurdly false, and one that is almost impossible to prove to boot.  But somehow I suspect that just by asking this absurd little question, one may get a closer view of prehistoric reality than what has dominated our belief system.

To read more:

Scientists find the king of the feathered dinosaurs
http://www.msnbc.msn.com/id/46954385/ns/technology_and_science-science

Asteroid Framed for Murdering Dinosaurs

From Space.com:

The source of the asteroid that killed off the dinosaurs 65 million years ago remains a mystery, a new study finds.

Some researchers had thought the deadly asteroid was a piece of a larger space rock called Baptistina. Baptistina broke apart after a massive in-space collision about 160 million years ago, the theory went, spawning a swarm of mountain-size chunks of rock. One of those eventually slammed into Earth, killing off the dinosaurs and many other species.

Scientists are confident that a 6-mile-wide (10-kilometer asteroid) is indeed what wiped out the dinosaurs. But new observations from NASA's Wide-field Infrared Survey Explorer (WISE) space telescope suggest the space rock didn't come from Baptistina.

The timing just isn't right, according to the new study....

Origin of Dinosaur-Killing Asteroid Is Still a Mystery
20 September 2011
http://www.space.com/13008-dinosaur-killing-asteroid-mystery-nasa.html

The Big Burp

From Yahoo News:
The mass extinction that opened the door for the rise of the dinosaurs about 201 million years ago may have been caused by a spike in carbon pumped into the atmosphere — most likely by methane released from the seafloor, a new study indicates.

This spike appears to have accelerated the climate change already under way, ultimately leading to the end-Triassic extinction, the researchers say.

Scientists already suspected that rapid warming and changes to ocean chemistry at the time killed off the dinosaurs' competitors, allowing their era to begin. And they knew that, at the time, eruptions of lava through fissures in the Earth's crust pumped carbon dioxide into the atmosphere.

But this new study indicates that something more than the 600,000 years of eruptions, more massive than anything in human history, pushed about half of species to extinction...

Earth's Methane Burp Cleared Way for Dinos
Wynne Parry
7-21-11
http://news.yahoo.com/earths-methane-burp-cleared-way-dinos-183007059.html

Scientists: Humans Are Fucked

From LiveScience.com:

Are humans causing a mass extinction on the magnitude of the one that killed the dinosaurs?

The answer is yes, according to a new analysis - but we still have some time to stop it.

Mass extinctions include events in which 75 percent of the species on Earth disappear within a geologically short time period, usually on the order of a few hundred thousand to a couple million years. It's happened only five times before in the past 540 million years of multicellular life on Earth. (The last great extinction occurred 65 million years ago, when the dinosaurs were wiped out.) At current rates of extinction, the study found, Earth will enter its sixth mass extinction within the next 300 to 2,000 years.

"It's bittersweet, because we're showing that we have this crisis," study co-author Elizabeth Ferrer, a graduate student in biology at the University of California, Berkeley, told LiveScience. "But we still have time to fix this."

Others aren't so optimistic that humans will actually do anything to stop the looming disaster, saying that politics is successfully working against saving species and the planet.

Species go extinct all the time, said Anthony Barnosky, the curator of the Museum of Paleontology at UC Berkeley and another co-author of the paper, which appears in today’s (March 2) issue of the journal Nature. But new species also evolve constantly, meaning that biodiversity usually stays constant. Mass extinctions happen when that balance goes out of whack. Suddenly, extinctions far outpace the genesis of new species, and the old rules for species survival go out the window...

The culprits for the biodiversity loss include climate change, habitat loss, pollution and overfishing, the researchers wrote.

"Most of the mechanisms that are occurring today, most of them are caused by us," Ferrer said.

So can we fix it? Yes, there's time to cut dependence on fossil fuels, alleviate climate change and commit to conservation of habitat, the study scientists say. The more pressing question is, will we?

Barnosky and Ferrer both say they're optimistic that people will pull together to solve the problem once they understand the magnitude of the looming disaster. Jablonski puts himself into the "guardedly optimistic category."

"I think a lot of the problems probably have a lot more to do with politics than with science," Jablonski said.

That's where Paul Ehrlich, the president of the Center for Conservation Biology at Stanford University and author of "The Population Bomb" (Sierra Club-Ballantine, 1968), sees little hope.

"Everything we're doing in Washington [D.C.] today is working in the wrong direction," Ehrlich, who was not involved in the research, told LiveScience. "There isn't a single powerful person in the world who is really talking about what the situation is … It's hard to be cheery when you don't see the slightest sign of any real attention being paid."

Other researchers take an upbeat view...

Humans on Verge of Causing 6th Great Mass Extinction
Stephanie Pappas
02 March 2011
http://www.livescience.com/13038-humans-causing-sixth-mass-extinction.html

Most dinosaurs were vegetarian, research suggests

http://www.telegraph.co.uk/science/dinosaurs/8214257/Most-dinosaurs-were-vegetarian-research-suggests.html

Most dinosaurs were vegetarian, research suggests
Most dinosaurs were vegetarian rather than meat-eating beasts, research suggests.
Andy Bloxham
21 Dec 2010

While Tyrannosaurus Rex sums up the image of a dinosaur wreaking terror by ripping flesh with powerful jaws, many of its closest relatives were more content nibbling leaves.

A new study of the diet of 90 species of theropod dinosaurs challenged the conventional view that nearly all theropods hunted prey, especially those closest to the ancestors of birds.

Rather it showed that among the most bird-like dinosaurs known as coelurosaurs plant eating was a common way of life.

Their diet may have also helped them survive and exploit new environments becoming the most successful group of dinosaurs throughout the Cretaceous Period, 145-65 million years ago.

Dr Lindsay Zanno of the Chicago Field Museum said: "Most theropods are clearly adapted to a predatory lifestyle, but somewhere on the line to birds, predatory dinosaurs went soft."

Theropods are a group of bipedal dinosaurs colloquially known as "predatory" dinosaurs and include the iconic hunters Tyrannosaurus and Velociraptor.

Among theropod dinosaurs, all modern birds and several groups of their closest extinct relatives belong to a subgroup known as Coelurosauria.

Most were feathered and most intelligent dinosaurs and those with the smallest body sizes also belong to this group.

However researchers have been only left with fossilized bones and teeth to work with and so had to deduce their diets.

For example the bone-crunching teeth and jaws of Tyrannosaurus rex were the tools of a megapredator or that the tooth batteries of Triceratops were used for shearing plant material.

However many coelurosaurian dinosaurs have more ambiguous adaptations such as peg-like teeth at the front of the mouth or no teeth at all so determining their diet has been a challenge.

Dr Zanno added: "These oddball dinosaurs have been the subject of much speculation but until now, we have not had a reliable way to choose between competing theories as to what they ate."

But a small number of fossilized dinosaur dung, stomach contents, tooth marks, the presence of stones within the stomach that serve as a gastric mill for digesting vegetation have been found along with a number of species.

And two dinosaur species preserved locked in the throes of combat have been found to cast light on the mystery of what dinosaurs ate.

The researchers found almost two dozen anatomical features statistically linked to direct evidence of herbivory including a toothless beak.

"Once we linked certain adaptations with direct evidence of diet, we looked to see which other theropod species had the same traits. Then we could say who was likely a plant eater and who was not."

Applying their data on diet, the researchers found that 44 theropod species distributed across six major lineages were eating plants and that the ancestor to most feathered dinosaurs and modern birds had probably already lost its appetite for flesh alone.

Because plant eating was found to be so widespread in Coelurosauria, the hypercarnivorous habits of T. rex and other meat eating coelurosaurs like Velociraptor should be viewed "more as the exception than the rule."

Besides identifying diet, the researchers analyzed whether different groups of coelurosaurs followed the same evolutionary pathways toward an herbivorous diet.

They found that over time, species lost their flesh-rending teeth, developing strange tooth types such as peg, wedge, and leaf-shaped teeth, and ultimately, some lost most or all of their teeth altogether and replaced them with a bird-like beak.

The beaks then continued to evolve into a myriad of forms and help support a high degree of dietary diversity in modern birds.

One theory why they were so successful was that the break up of continents and origin of new habitat opened up new dietary niches for coelurosaurs to explore.

Dr Zanno said: "The ability to eat plant materials may have played a pivotal role in allowing coelurosaurian dinosaurs to achieve such remarkable species diversity.

"But more study is needed to understand what role dietary shifts may play in evolutionary processes."

Because ceolurosaurian dinosaurs include the closest extinct relatives of birds, understanding their biology is also extremely important to understanding how, why, and under what conditions birds evolved and first took flight.

"We don't know what drove the ancestors to birds to take flight," she says, "seeking food in the trees is just one of many possibilities."

Using statistical analysis to find correlations between physical traits and diet could offer a new window as to how evolution works.

"Being able to establish diet in extinct animals with confidence will allow us to start tackling even broader questions, such as whether animals tend to increase in body and diversity when they evolve herbivory."

The findings are published in the journal Proceedings of the National Academy of Sciences.

Do Dinosaurs Still Exist?

http://www.livescience.com/strangenews/090604-lost-world-dinosaurs.html

Do Dinosaurs Still Exist?
Benjamin Radford
LiveScience's Bad Science Columnist
Thu Jun 4, 2009

The idea of still-living dinosaurs has captured the public imagination for well over a century.

Arthur Conan Doyle, creator of Sherlock Holmes, published a 1912 novel called "The Lost World," set in the remote Venezuelan jungle where dinosaurs still survive in modern times. Films such as "Jurassic Park" and "Land of the Lost," which opens Friday, were inspired by Conan Doyle's vision - in fact the sequel to "Jurassic Park" was titled "The Lost World."

The animated film "Up" (currently No. 1 at the box office) also takes place in this lost world, the plot involving the discovery of an unknown, multicolored dinosaur.

For most of us, fiction is good enough. Yet some believe that giant dinosaurs still exist today, just beyond the reach of scientific proof.

Lake monsters

There are hundreds of lakes harboring reputed monsters around the world, from Scotland's Loch Ness to Canada's Lake Okanagan, America's Lake Champlain to Argentina's Lake Nahuel.

The explanations for such monsters include dinosaurs and dinosaur-like animals. Believers and researchers ask what else could be so big, and account for the sightings.

Many believe that lake and sea monster reports can be "explained" as animals like the plesiosaur (a long-necked aquatic reptile that reached 40 feet in length) or the ichthyosaur (shonisaurus sikanniensis), which were as big as a submarine.

Mokele-Mbembe

In the remote jungles of central Africa, native stories tell of a dinosaur-like creature said to be up to 35 feet long, with brownish-gray skin and a long, flexible neck. Many believe that it lives in caves it digs in riverbanks, and feeds on elephants, hippos, and crocodiles.

Roy Mackal, a retired University of Chicago biologist who conducted two expeditions in search of the Mokele-Mbembe, believes that the descriptions of the creature suggest "a small sauropod dinosaur."

Despite more than two dozen searches for the "living dinosaur" as recently as last year, evidence is elusive. There are no photographs or films of the creature, no bones or teeth, no evidence beyond stories and anecdote.

The surprising truth

Of course the fatal flaw in the idea that giant dinosaurs still lurk in remote jungles or cold, deep lakes is that all the evidence suggests they died out about 65 million years ago. Many of the lakes said to hide dinosaurs were created only about 10,000 years ago.

If dinosaurs had existed up until much more recently - say, the Nixon administration or even Shakespeare's time - the likelihood of a few remaining, lonely huge dinosaurs might be plausible. But 65 million years is a long time for giant dinosaurs to live and die without leaving any recent fossils.

Yet scientifically speaking, not all dinosaurs died out. Most of us see dinosaurs every day, and some people even have them in their homes. Birds are the modern version of dinosaurs, though seeing Will Ferrell or Jeff Goldblum running terrified from an approaching pigeon just isn't very dramatic.

Benjamin Radford is managing editor of the Skeptical Inquirer science magazine. His books, films, and other projects can be found on his website. His Bad Science column appears regularly on LiveScience.

Giant Titanoboa snake ruled the earth

http://www.timesonline.co.uk/tol/news/uk/science/article5662915.ece

February 5, 2009
Giant Titanoboa snake ruled the earth after the dinosaurs
The Titanoboa grew to 45ft or more
Lewis Smith, Environment Reporter

A titanic snake that snacked on crocodiles and was longer than a London bus has been identified as the top predator to walk, or at least slither, the land when the dinosaurs disappeared.

It weighed 1.25 tonnes and with a length of 45 feet or more it would have been able to take on and eat pretty much any other animal it came across.

The newly discovered type of snake, named Titanoboa in honour of its immense size, was for 10 million years the largest land predator on earth.

At least 28 individual specimens have been uncovered in Colombia and, with all of them being around 40 feet long, researchers said it is likely the species could have reached much further than 45 feet.

Fossils recovered from the site over the last five years have given researchers the most detailed picture yet of life in tropical South America in the years following the disappearance of the dinosaurs.

Alongside the enormous snakes, which were so wide it would have been a squeeze for them to get through a doorway, were fossils of turtles and giant crocodile-like dyrosaurs.

Other fossil finds, including fish, gastropods and plants such as palms, are providing researchers with their first glimpses of the tropical ecosystem that laid the foundations for the Amazon forest.

Jonathan Bloch, of the University of Florida, was one of the researchers who analysed the remains of the snake, the biggest that ever lived.

He said: “It was not only the biggest predator in the region, as far as we know, but it was the largest terrestrial vertebrate known on the face of the planet for at least 10 million years.

“It could have eaten pretty much anything that came its way. If we had to guess, it probably ate a lot of fish and crocodyliforms.

“It is possible that the extinction of the dinosaurs 65 million years opened up the opportunity for the evolution of another top-predator such as Titanoboa.”

He added: “Truly enormous snakes really spark people's imagination, but reality has exceeded the fantasies of Hollywood. The snake that tried to eat Jennifer Lopez in the movie Anaconda is not as big as the one we found.”

Carlos Jaramillo, of the Smithsonian Institution in Panama, said the specimens uncovered from the mine are likely to have been merely average in size, meaning that some individuals would have been much bigger.

The reticulated python, from South East Asia, is the longest living species recorded, according to Guinness World Records, with one individual reaching almost 33 feet long but the average length for the species is only 20 feet.

The size of the cold-blooded Titanoboa indicated to researchers that the tropical coastal river system it occupied would have been warmer than the tropics today. Using the snake’s proportions they worked out that the tropics 60 million years ago would have been about 32C, some 4C warmer than now.

Jason Head, of the University of Toronto in Canada and the Smithsonian Institution, said as the findings were published in the journal Nature: “The discovery of Titanoboa challenges our understanding of past climates and environments, as well as the biological limitations on the evolution of giant snakes.”

New Nahuelito Mystery Photo

http://www.cryptomundo.com/cryptozoo-news/nahuelito-pic09/

New Nahuelito Mystery Photo
Loren Coleman
January 17th, 2009

A new image of the head and neck of an alleged Lake Monster of Argentina is worthy of a viewing here. What could it be?

A Spanish language (Infobae) item on the Nahuelito image was published late last year, accompanying the above photograph. My translation of the text, more or less, via robot and common sense, reads:

It is “Nahuelito”?

A man sent this photograph to a newspaper of Bariloche and planted a new seed of doubt about the existence of this mythical animal. This time, the image was captured in Mascardi Lake.

The image published in the Matutinal Rionegrino the Cordillerano shows an animal similar to a serpent that shows itself on the surface of the water.

“I thought that they were huillines [river otters], when I saw it diving under the water, but when she showed [again] I was surprised. It looked little like any other animal that I had seen before, and I was scared by its presence when it appeared,” related the reader who sent the photography to the newspaper.

For the aware, this could be a test of the existence of the “Nahuelito.”

But for the skeptical ones, it is only a trunk floating in the water.

The history of “Nahuelito”:

It is an unknown aquatic creature, who, according to the popular belief, lives in Nahuel Huapi Lake in Argentina.

The legend goes back to indigenous stories and the first registered sighting dates back to 1910, when George Garret recorded he saw “about 400 meters distance away a creature whose visible part measured between 5 and 7 meters in length and excelled about two meters out of the water.”

In 1897, the credible Dr. Onelli, director of the Zoological Park of Buenos Aires, began to receive sporadic information about a strange creature that inhabited the Lagos patagónicos and organized an expedition in search of it. The search did not obtain any positive results.

More recently, in 1960, the Argentina Navy encountered in the lake an unidentified submarine object for 18 days, without being able to identify it.

The most popular hypothesis is that the prehistoric monster, “Nahuelito,” is a survivor of the time of the dinosaurs, probably a “plesiosaur.”

Please see my and Patrick Huyghe’s lake monster field guide, on pages 119-121 and 294-295, for more on the history of the sightings of Nahuelito.

The question remains, what does the above photograph show? A turtle does not have teeth, right? Is it a swimming lizard? An otter? Yes, an otter? A log with painted eyes and teeth? Some other kind of fake? What could it be?

The two photographs of Nahuelito, allegedly taken on April 15, 2006, are below:

Tip of the hat to Above Top Secret for bringing this 2008 image to our attention.

Biggest Dinosaurs Grew Huge by Not Chewing

http://news.nationalgeographic.com/news/2008/10/081009-dinosaur-big.html

Biggest Dinosaurs Grew Huge by Not Chewing Their Food
Kate Ravilious
for National Geographic News
October 9, 2008

Dinosaurs known as sauropods—the largest land animals that ever lived—grew huge and were an evolutionary success in part because they didn't bother to chew their food, new research suggests.

Sauropods weighed up to 88 tons (80 metric tons)—ten times more than an African elephant—and measured as high as 23 feet (7 meters).

The group of dinosaurs, which included the brachiosaurus and diplodocus, loomed over the animal kingdom for more than 140 million years until the late Cretaceous period, 65 million years ago. (See a brachiosaurus herd.)

Scientists think the animals evolved to be so large to discourage big predators, like Tyrannosaurus rex, from eating them. But how they maintained such massive body sizes has remained mysterious.

The herbivores, or plant-eaters, had hardly any teeth and are thought to have swallowed their food whole—an entire bush in one gulp, for example. They browsed large areas, barely moving and consuming vast quantities in short periods of time.

So they needed long necks to reach food high in trees and a huge gut to process and break down their unchewed meals, said Martin Sander, a palaeontologist at the University of Bonn in Germany and co-author of the study, published tomorrow in the journal Science.

"You can only have this long neck if you don't chew your food, otherwise your head would be full of teeth and too heavy to support," he said.

Paul Upchurch, an expert on sauropods from University College London, said that "most palaeontologists agree that feeding is the key to understanding sauropod gigantism."

Survival Strategies

To outgrow their predators, sauropods didn't just need lots of food. They also needed to develop fast, so they could attain their full size before being eaten, experts said.

Sauropod bones show that they did indeed grow swiftly. A 22-pound (10-kilogram) hatchling could become a 220,000-pound (100,000-kilogram) grown-up in about 20 to 30 years—quick by dinosaur time.

"This tells us that they must have been warm-blooded and had a high metabolic rate compared to cold-blooded creatures," said the University of Bonn's Sander.

Like all dinosaurs, sauropods laid nestfuls of eggs. By producing so many young at a time, "a population could recover quickly, even after a big catastrophe," Sander said.

Large modern mammals, such as elephants, give birth to far fewer offspring, raising their chances of extinction should a disaster occur.

So why don't we see gigantic elephants and crocodiles roaming around today?

Experts think that reptiles, such as crocodiles, still maintain the egg-laying advantage, but their cold blood prevents them from growing fast enough to reach a great size.

Mammals have warm blood, but can't grow as big as sauropods due to their slow reproductive strategy and the need to chew their food.

Huge Flying Reptiles Ate Dinosaurs

http://www.livescience.com/animals/080527-giant-reptile.html

Huge Flying Reptiles Ate Dinosaurs
By Jeanna Bryner, Senior Writer
27 May 2008

A group of flying reptiles called Quetzalcoatlus may have strolled along a fern prairie eating baby dinosaurs for lunch.

With a name like T. rex, you'd expect to be safe from even the fiercest paleo-bullies. Turns out, ancient, flying reptiles could have snacked on Tyrannosaurus Rex babies and other landlubbing runts of the dinosaur world.

A new study reveals a group of flying reptiles that lived during the Age of Dinosaurs some 230 million to 65 million years ago did not catch prey in flight, but rather stalked them on land.

Until now, paleontologists pictured the so-called "winged lizards" or pterosaurs as skim-feeders. In this vision, the creatures would have flown over lakes and oceans grabbing fish from the water's surface, much as gulls do today.

The new findings, detailed this week online in the journal PLoS ONE, don't ground the animals totally.

"In our hypothesis, flight is primarily a locomotive method," said co-researcher Mark Witton of the University of Portsmouth in England. "They're just using it to get from point A to point B. We think the majority of their lives, when they're feeding and reproducing, that's all being done on the ground rather than in the air."

To uncover these feeding habits, Witton and Portsmouth colleague Darren Naish analyzed fossils of a group of toothless pterosaurs called azhdarchids, which are much larger on average than other pterosaurs. For example, one of the largest azhdarchids, Quetzalcoatlus, weighed about 550 pounds (250 kilograms) with a wingspan of more than 30 feet (10 meters) and a height comparable to a giraffe.

Witton and Naish learned that more than 50 percent of the azhdarchid fossils had been found inland. Other skeletal features, including long hind limbs and a stiff neck, also didn't fit with a mud-prober or skim-feeder.

"All the details of their anatomy, and the environment their fossils are found in, show that they made their living by walking around, reaching down to grab and pick up animals and other prey," Naish said.

A skim-feeder, such as a gull, trawls its lower jaw through the water, eventually smacking into a fish or shrimp and pulling it from the water. "Regardless of what they hit, the impact force drives the head and neck underneath the body and into the water, thus requiring a hugely flexible neck," Witton said.

This is the case with gulls and pelicans (which are considered plunge divers), but azhdarchid's neck, despite potentially reaching nearly 10 feet (3 meters) in length, was super stiff. "Whatever these animals were doing, it had to involve minimal neck action," Witton said.

Their tiny feet also ruled out wading in the water or probing the soft mud for food. "Some of these animals are absolutely enormous," Witton told LiveScience. "If you go wading out into this soft mud, and you weigh a quarter of a ton, and you've got these dinky little feet, you're going to just sink in."

The reptile's head also was pretty lengthy, up to 10 feet (3 meters). So Witton said an azhdarchid would only have to dip its head part way to the ground, enough for the tip of its jaws to touch down, to hunt and feed on terrestrial prey. Back before they went extinct 65 million years ago during the event that also killed off non-avian dinosaurs, these pterosaurs could lunch on animals ranging from small bird-like Velicoraptors to T. rex babies to amphibians.

Did mozzies, not a meteor, do for the dinosaurs?

http://www.dailymail.co.uk/pages/live/articles/technology/technology.html?in_article_id=506440&in_page_id=1965

Did mozzies, not a meteor, do for the dinosaurs?
6th January 2008

Disease-carrying mosquitoes could have killed off dinosaurs instead of a cataclysmic comet
The theory goes that dinosaurs were wiped out after an asteroid smashed into the Earth 65million years ago.

But now it has been suggested they were sent into eternity by an equally catastrophic but somewhat smaller threat - biting insects.

Disease spread by mosquitoes, mites and ticks was probably the major factor that finished off the reptiles, say scientists.

The insects could have also made it harder for dinosaurs to survive by changing the nature of plant life.

Bees and other pollinators helped promote the rapid spread of flowering plants, leading to the loss of vegetarian dinosaurs' traditional food sources. As the planteating dinosaurs declined, so would their predators.

The theory helps explain why dinosaurs took so long to die off, say husband-and - wife team George and Roberta Poinar.

According to the most widely accepted explanation, the dinosaurs vanished after an asteroid or comet hit the Earth between the Cretaceous and Tertiary periods.

Another theory is that they were driven to extinction by massive volcanic eruptions in India, which led to extreme climate change.

But George Poinar, a courtesy professor of zoology at Oregon State University, points out that they did not disappear immediately.

Their extinction was drawn out over hundreds of thousands or even millions of years.

An asteroid impact should have led to an abrupt extinction, and climate change would probably also have wiped them out in a relatively short time, he said.

But emerging diseases spread by biting insects, combined with the spread of flowering plants, and competition with insects for plant resources, was "perfectly compatible" with a lengthy process of extinction.

The Poinars outline their theory in What Bugged The Dinosaurs? Insects, Disease And Death In The Cretaceous, published by Princeton University Press.

The professor said examination of insects preserved in amber found organisms which can cause malaria, dysentery "and other abdominal disturbances".

The infections the insects carried would have caused repeated epidemics that slowly wore down dinosaur populations, which had little or no immunity.

Professor Poinar added: "Other geologic and catastrophic events certainly played a role.

"But by themselves, such events do not explain a process that in reality took a very, very long time, perhaps millions of years. Insects and diseases do provide that explanation."

Disease threatens mass extinction of frogs

http://www.telegraph.co.uk/earth/main.jhtml;jsessionid=E2SJBPKLBRWD5QFIQMGSFGGAVCBQWIV0?xml=/earth/2008/01/01/eafrog101.xml

Disease threatens mass extinction of frogs
By Paul Eccleston
01/01/2008

An international campaign has been launched to help save the world’s amphibians from extinction.

Scientists fear the largest mass extinction since the disappearance of the dinosaurs because of a deadly disease which is sweeping through populations of frogs, toads, newts, salamanders and caecilians across the globe.

Amphibians are under threat

Amphibians have thrived for hundreds of millions of years but as many as half of all species could perish unless a solution is found. The spread of the parasitic fungus amphibian chytrid, which has proved deadly for hundreds of amphibian species, may have been made worse by the effects of global warming. The disease has so far proved unstoppable in the wild and can kill 80 per cent of native amphibians within months once it has taken hold.

Amphibians are important as an 'indicator species’ - similar to canaries in a coal mine - who serve as a warning when there is something wrong with the environment. Now 2008 has been designated Year of the Frog by conservationists to raise awareness of the plight of amphibians and to raise the funds needed for a concerted worldwide effort to save them.

The Amphibian Conservation Action Plan (ACAP) aims to protect the habitat of the amphibians while at the same time finding answers to the environmental problems they face.

The biggest initiative will be an amphibian version of Noah’s Ark costing an estimated £30m where the most vulnerable species will be moved into protected areas in zoos, aquariums and other institutions around the world so their future survival can be guaranteed.

advertisementThe ambitious rescue plan is being organised by the IUCN/SSC Conservation Breeding Specialist Group, the IUCN/SSC Amphibian Specialist Group, and the World Association of Zoos and Aquariums (WAZA).

“Widespread extinction of amphibians would be catastrophic,” said Jeffrey P. Bonner, chairman of Amphibian Ark and president and CEO of the St. Louis Zoo.

“In addition to their intrinsic value, they offer many benefits and are a critical part of a healthy world. They play an important role in the food web as both predator and prey, eating insects which benefits agriculture and minimizes disease spread. Their skin also has substances that protect them from some microbes and viruses, offering promising medical cures for a variety of human diseases.

The conservation groups hope the captive management plan will buy time for the most endangered species which will eventually be reintroduced back into the wild once the threats they face have been removed.

It is hoped the Year of the Frog campaign will raise awareness of the crisis among media, educators, corporations, philanthropists and governments and will generate the funding needed to make the campaign a success.

Sir David Attenborough, who is patron of the campaign, said, “The global zoo and aquarium community has taken on this challenge with enthusiasm and is providing appropriate facilities and breeding grounds within their institutions. But implementation calls for financial and political support from all parts of the world. Without an immediate and sustained conservation effort to support captive management, hundreds of species of these wonderful creatures could become extinct in our own lifetime.”

Amphibians are severely affected by habitat loss, climate change, pollution and pesticides, introduced species, and over-collection for food and pets.

Jörg Junhold, Ph.D., chair of the Amphibian Ark Year of the Frog campaign and director of Zoo Leipzig, said: “It is of utmost importance to raise awareness among national governments, world media, school educators, corporations, philanthropists, and the general public about the fragility of amphibians and the enormous responsibility that each of us has in trying to rescue the amphibians in danger.”

“The outcome of the Amphibian Ark project will be that we will have saved hundreds if not thousands of species from extinction. We also will have developed a capacity both within our institutions and globally to continue to provide amphibian species with care and protection when needed, formed a true partnership between offsite and onsite components of conservation, and demonstrated to the world that zoos and aquariums are essential conservation organizations.”

Distant space collision meant doom for dinosaurs

http://news.yahoo.com/s/nm/20070905/sc_nm/asteroid_dinosaurs_dc_1

Distant space collision meant doom for dinosaurs
By Will Dunham
Wed Sep 5, 2007

A collision 160 million years ago of two asteroids orbiting between Mars and Jupiter sent many big rock chunks hurtling toward Earth, including the one that zapped the dinosaurs, scientists said on Wednesday.

Their research offered an explanation for the cause of one of the most momentous events in the history of life on Earth -- a six-mile-wide (10-km-wide) meteorite striking Mexico's Yucatan peninsula 65 million years ago.

That catastrophe eliminated the dinosaurs, which had flourished for about 165 million years, and many other life forms, and paved the way for mammals to dominate the Earth and the eventual rise of humankind, many scientists believe.

The impact is thought to have triggered a worldwide environmental cataclysm, expelling vast quantities of rock and dust into the sky, unleashing giant tsunamis, sparking global wildfires and leaving Earth shrouded in darkness for years.

U.S. and Czech researchers used computer simulations to calculate that there was a 90 percent probability that the collision of two asteroids -- one about 105 miles wide and one about 40 miles wide -- was the event that precipitated the Earthly disaster.

The collision occurred in the asteroid belt, a collection of big and small rocks orbiting the sun about 100 million miles from Earth, the researchers report in this week's issue of the journal Nature.

The asteroid Baptistina and rubble associated with it are thought to be leftovers, the scientists said.

Some of the debris from the collision escaped the asteroid belt, tumbled toward the inner solar system and whacked Earth and our moon, along with probably Mars and Venus, said William Bottke of the Southwest Research Institute in Boulder, Colorado, one of the researchers.

DEADLY COLLISION

The collision is believed to have doubled for a while the number of impacts occurring in this part of the solar system.

In fact, while the bombardment of this region of the solar system due to this shower of debris peaked about 100 million years ago, the scientists said the tail end of the shower continues to this day. Bottke said many existing near-Earth asteroids can be traced back to this collision.

"Imagine breaking up a big, big boulder on top of a hill and all the fragments rolling down the hill. And somewhere at the bottom is a village called Earth," Bottke said in a telephone interview.

The dinosaur-destroying meteorite, thought to have measured 6 miles across, plunged into Mexico's Yucatan Peninsula and blasted out the Chicxulub (pronounced CHIK-shu-loob) crater measuring about 110 miles wide. The researchers looked at evidence on the composition of this meteorite and found it consistent with the stony Baptistina.

The researchers estimated that there also was about a 70 percent probability that the prominent Tycho crater on the Moon, formed 108 million years ago and measuring about 55 miles

across, also was carved out by a remnant of the earlier asteroid collision.

Philippe Claeys of Vrije Universiteit Brussel in Belgium, who was not involved in the research, said by e-mail the findings were "clear evidence that the solar system is a violent environment and that collisions taking place in the asteroid belt can have major repercussions for the evolution of life on Earth."

Bottke emphasized that point. "Dinosaurs were around for a very long time. So the likelihood is they would still be around if that event had never taken place," Bottke said.

"Was humanity inevitable? Or is humanity just something that happened to arise because of this sequence of events that took place at just the right time. It's hard to say."