Mary Anning
Courtesy Public domain via WikipediaToday marks the 163rd anniversary of the death of Mary Anning, early British fossilist who discovered the first complete remains of the marine reptiles ichthysaurus and plesiosaurus. Mary sold fossils she collected around Lyme Regis, England, to support her severely impoverished family after her father had died. She had no formal education, other than what her parents had taught her about collecting, but her fossils and knowledge of them were sought out by many of the top geologists of her time. Local folks viewed her activities with suspicion and apprehension since the biblical view of creation was still widely held, and the very idea that the fossils she collected were of creatures that went extinct was disturbing to many. Anning was made an honorary member of the Geological Society of England just prior to her death in 1847. Her portrait and some of the fossils she found are displayed in the British Museum in London.
SOURCES
Mary Anning bio
Wikipedia article
Tags : Asteroid found guilty of killing dinosaurs!!
in Earth and Space Science, Life Science, and Biological Populations Change Over Time
What sent the dinosaurs packing?: The number one suspect, a gigantic asteroid, has finally been convicted of the crime.
Courtesy Mark RyanAfter studying all available evidence and listening to alternative theories (and despite no eyewitnesses), a panel of 45 international scientists has decided it was a huge asteroid that killed all the non-avian dinosaurs some 65 million years ago.
The asteroid, described as a 7 mile-in-diameter chunk of space rock, has been the prime suspect in the ruling reptile’s demise ever since scientists Luis Alvarez and his son Walter first identified a one-inch layer of iridium in Late Cretaceous-age rock exposures throughout the world. The layer was located exactly at the point in the rock record where the Cretaceous period ended, and the Tertiary period began (K-T boundary). 
Smoking gun for dinosaurs' demise: K-T Boundary with 1-inch iridium layer (arrow) exposed 10 miles west of Trinidad, Colorado. The element iridium is very rare on Earth but concentrated in meteors and comets. The same iridium layer is found in several exposures around the world, and corresponds in age with the Chicxulub meteor crater in Mexico's Yucatan Peninsula. The layer marks the end of the Cretaceous era, and no non-avian dinosaur remains have ever been found above the boundary. The coal layers above and below the iridium suggests a swampy environment when the layer was laid down in this area of Colorado.
Courtesy Mark RyanThey predicted a meteor impact crater of the same age would be found as the source of the iridium since the element is rare on Earth but common in outer space. Then in 1990 their predictions were verified when the Chicxulub impact crater was discovered in Mexico.
Although the impact site was mostly submerged off the north coast of the Yucatan Peninsula, samples taken from it dated to the end of the Cretaceous period. This and other corroborating evidence helped bolster the killer asteroid hypothesis as the primary theory for the extinction event that wiped out 70-75 percent of life on Earth including non-avian dinosaurs, and other large reptiles. The asteroid is estimated to have slammed into Earth traveling 10 times faster than a rifle bullet, and released the energy of a billion atomic bombs. The impact instantly vaporized a large area of terrain, and sent an explosion of dust and rocky debris up into space, much of which fell back into the atmosphere in a fiery rain. It left a crater 110 miles across, and a cloud of dust circling the planet for weeks. The diminished sunlight would have disrupted the environment severely, including the food chain. Mammals and other smaller creatures were able to survive across the boundary and flourish in later periods.
But not everyone was convinced by the evidence. Other causes for the mass extinction, such as extreme volcanism in India, falling sea levels, disease epidemics, and even fungal infection were all tossed around as possible culprits.
But in the end it seems the evidence implicating the asteroid in the K-T* extinction event was just too strong, and after much deliberation, the impact has been determined as the official cause of death. The panel published its decision in the latest issue of Science.
*“K-T” stands for Cretaceous-Tertiary, however, use of the term Tertiary is being discouraged now, and the time span it occupied has been replaced with the Paleogene and Neogene periods. So a more proper, up-to-date term would be Cretaceous-Paleogene or K-Pg extinction event.
LINKS AND SOURCES
More about dinosaur extinction
BBC story
Impact theory counterview
Frozen in time: Unique fossil shows snake coiled among nest of dinosaur eggs and titanosaur hatchling.
Courtesy PLoS Biology
Diagram of fossil
Courtesy PLoS BiologyCheck out this amazing fossil showing the remains of a snake coiled around a nest of dinosaur eggs, including a nearby titanosaur hatchling. The fossil was found 26 years ago in northwestern India, and was originally thought to contain remains of eggs and baby dinosaur bones. But recent re-evalutions revealed some of the bones were actually those of a new species of snake named Sanajeh indicus. The incredible 67 million-year-old fossil is the first of its kind, and suggests that snakes preyed on dinosaurs, just as they prey on birds today. A newly hatched titanosaur would have been easy pickings for the 11.5 foot S. indicus, but an adult titanosaur - which grew to more than 100 feet in length - would have been another story. Scientists think the unique Cretaceous fossil resulted from an ancient landslide that buried the snake just when it was about to go after its next meal. Here's a photo of the incredible fossil and along with a diagram of what it contains. You can read the whole story at PLoS Biology where the research has been published.
Rex in the hen house
Courtesy Mark RyanA new study came out last week that appeared destined to shake up the current line of thought that birds descended from dinosaurs. Birds share common traits with some dinosaurs, including furculas (wishbones), hollow bones, and other skeletal features, which scientists have interpreted to mean the former descended from the latter. But now a new study by researchers at Oregon State University, it may have happened just the opposite way.
"We think the evidence is finally showing that these animals which are usually considered dinosaurs were actually descended from birds, not the other way around," said John Ruben, a professor of zoology at OSU, and the study’s lead author.
The study involved the fossil of a Microraptor, a dromaeosaurid dinosaur with evidence of feathers on both its arms and legs. Studying the skeletal remains, Ruben and his colleagues constructed 3-dimensional models that they tested for flight capabilities. Their study showed Microraptor’s structure better suited to be glider rather than a flyer. From this Ruben extrapolated that it made more sense that Microraptor descendents came down from the trees and eventually evolved into flightless birds we call dromaeosaurs or raptors.
"Raptors look quite a bit like dinosaurs but they have much more in common with birds than they do with other theropod dinosaurs such as Tyrannosaurus," he said. The study appears in the journal for the Proceedings of the National Academy of Science (PNAS).
Sounds good at first, and I have to admit I was smitten with the idea. But not everyone feels the same way.
Over at the Smithsonian’s Dinosaur Tracking blog, freelance science writer Brian Switek has pointed out that Ruben’s proclamation is “actually only a commentary, or the equivalent of an opinion piece.”
He then goes on to point out some of the flaws in Ruben’s argument, particularly the uncertainty surrounding Microraptor’s place in the evolution of flight, and the lack of reasonable evidence that Velociraptor wasn’t a dinosaur. Switek doesn’t think Ruben’s claim stands up to scrutiny.
But what annoys Switek most is how the media inundates the various outlets with this kind of science news, giving it wide distribution and often, undeserved credibility.
“In this increasingly fragmented media landscape, knowledgeable science writers who recognize a fishy story when they see one are getting outnumbered. More often, websites and newspapers simply reprint press releases issued by universities and museums (science writers call this “churnalism”), and this policy sometimes lets questionable science slip through the cracks.” – Brian Switek
One of the reasons for this is the internet. There's just a huge amount of time and space that requires constant feedings of content now. It does make things difficult to sort through. There have been times I’ve begun researching some new science story to post on Science Buzz only to become frustrated with details that don’t seem to add up, confusing statements, info that counters other info, and outright misinformation. Some of it may be due to the writer(s) not being able to properly articulate or distill a particular idea or hypothesis for the general reader (I know I suffer from this occasionally). Sometimes it’s due to the fact that many science writers lack access to the papers themselves (most science journals require paid subscriptions to access anything beyond an abstract of the story), so writers are left with relying on press releases and abstracts or another writer’s thoughts on the subject (like I’m doing here). But other times it ends up being that there’s no real story at all, just a rehash of something from months or years ago that somebody figures needed to be in the headlines again.
To this end, paleontologist Dave Hone over at his Archosaur Musings blog recently posted “A guide for journalists reporting on dinosaur stories” that deals with some of issues raised here. It’s worth reading.
Science Buzz has also covered science writing issues in previous posts.
How to read/write science news
Bad Science Journalism
SOURCE and MORE INFO
ScienceDaily.com story
Microraptor gui: Bird or Dinosaur
Origin and Evolution of Birds
Barnum Brown - hot on the trail for fossils: I guess 110° in the shade sometimes warrants throwing on the old fur coat.
Courtesy Public domain via WikipediaWith this being Lincoln's, Darwin's, and even my grandfather George Hanzalik's birthday, the last thing we need is notice of yet another notable so and so born on this date. But Barnum Brown deserves some special attention. Named after the great circus huckster P. T. Barnum, Brown was born this day in Carbondale, Kansas in 1873, and grew up to be what some have called the "last of the great dinosaur hunters". Brown began his work as a paleontologist at the American Museum of Natural History in 1897 under the tutelage of Henry Fairfield Osborn . Barnum Brown traveled the U.S. collecting and buying up fossils for the museum. He was known for using dynamite to coax fossils out of the rocks, and for being impeccably dressed while on digs (see photo). 
Tyrannosaurus rex: Barnum Brown's most famous find.
Courtesy Public domainHis most famous discovery came out of the Hell Creek formation in Montana in 1902 when he found the first recorded remains of Tyrannosaurus rex.
MORE INFO
Barnum Brown bio
Barnum Brown bio on Wikipedia
Notice of new Barnum Brown biography (due out May 2010).
Dinosaur expressway: Although this one is near Denver, Colorado, a similar trackway has been discovered in China.
Courtesy Mark RyanScientists in China have discovered a trackway of some 3000 dinosaur footprints - all moving in the same direction - in the eastern region of Shandong province near the city of Zhucheng. The 100 million year-old tracks appear to be from several species. Click here for more info.
The Open Dinosaur Project
in Earth and Space Science, Life Science, Diversity of Organisms, Scientific Inquiry, and Biological Populations Change Over Time
Measuring the SMM camptosaurus: SMM paleo lab volunteers Becky Huset (left) and Neva Key consult over their ornithischian limb bone measurements for the Open Dinosaur Project.
Courtesy Mark RyanThe Open Dinosaur Project (ODP) allows anyone with an interest in paleontology, and access to skeletal information, scientific publications, or museum skeletons themselves the opportunity to be part of the compilation of an actual scientific paper. Paleontologists Andy Farke, Matt Wedel, and Mike Taylor make up the core ODP team, but only the core. The rest of the team is made up of individuals around the world. The hope is to put together a comprehensive database of information about the dimensions of limb bones (legs, arms, hands, and feet) of ornithischian (bird-hipped) dinosaurs in museums around the world with a goal of “investigating the evolution of locomotion and limb proportions in this group.”
“The Open Dinosaur Project fits very comfortably into that loose coalition of ideas: we’re trying to democratize science, open up data, blog the process, and make sure that the final publications are freely available to the world,” Mike Taylor said during a recent interview with the Brazilian science publication Ciência Hoje On-line.
Putting tape to toe: SMM volunteer Becky Huset measures the metatarsals and phalanx of the musuem's camptosaurus for the Open Dinosaur Project.
Courtesy Mark RyanTwo volunteers here at the Science Museum of Minnesota got themselves involved with this unique study. Becky Huset and Neva Key both work in the SMM paleo lab, usually hunched over fossils extracting them from rocks or preparing them for display. But recently, the two have spent time out on gallery floor measuring the limbs of some of the museum’s mounted ornithischian dinosaurs.
“We did the Camptosaurus and some cast bones from Stegosaurus from the collections,” Becky said. She added that measurements of the SMM Triceratops were already listed.
Why only ornithischian dinosaurs? Part of the reason was to keep the study somewhat manageable. But ornithischian dinosaurs also have an interesting evolution of locomotion that to date hasn’t been studied in depth. The dinosaur order radiated from a two-legged (biped) form into at least three different four-legged (quadruped) forms including armored dinosaurs (e.g. stegosaurs and ankylosaurs), ceratopsians (e.g. triceratops and chasmosaurus), and various ornithopod types, (e.g. camptosaurs, hadrosaurs, and iguanodontids).
.thumbnail.jpg "How to measure a scapcoracoid: One of several measuring aids available to project volunteers from the Open Dinosaur Project website.")
How to measure a scapcoracoid: One of several measuring aids available to project volunteers from the Open Dinosaur Project website.
Courtesy Open Dinosaur ProjectIn order to aid team members in gathering the proper information, instructions, templates, and other documents are available on the Open Dinosaur Project website. Diagrams explaining ornithischian limb osteology – including each bone’s proper name - are also on the site, as are illustrations showing exactly how to properly measure the dimensions of different bones. For those involved who don’t have access to museum specimens or material in other collections, the team leaders provide lists where prior publications with skeletal information can be accessed and mined for the study.
By last week, the Open Dinosaur Project had acquired nearly 1600 entries, but the results of all this work remain to be seen. The compiled data will be analyzed over the next couple months, and Farke, Wedel, and Taylor plan to begin writing the paper this spring. When completed the study will be submitted for publication in a peer-reviewed journal. If all goes as planned, after publication, the lead researchers will make all the data available online for future studies.
Now that their data has been entered on the ODP site, SMM volunteers Huset and Key will have their names included as contributors, and eligible to be included in the resulting paper.
"We wanted to get the general public excited about and involved in doing “real” science, working in cooperation with paleontologists. There is a great interest out there in paleontology, particularly dinosaurs. It’s amazing how many non-paleontologists read the technical literature! I thought, “Why not harness this enthusiasm?” There have been many people waiting for this sort of opportunity (even if they didn’t know it), and I think the response speaks for itself." – Andy Farke in Ciência Hoje On-line
Becky Huset enjoyed being involved with the project. “[It] sounded like a good idea,” she said. “I like having knowledge that is freely available to everyone, and it was a good way to contribute to a paper. Do some "real" work."
LINKS
Open Dinosaur Project website
Wedel’s & Taylor’s dino-related blog
More about Ornithischian dinosaurs
Osteology (the scientific study of bones)
Some of my dinosaur drawings from c. 1963: I was obviously partial to Stegosaurus although I seemed to be limited to a side view.
Courtesy Mark Ryan January 30th is Draw A Dinosaur Day. It also happens to be my birthday, and I can't think of a better way to celebrate than to draw a dinosaur and upload it to the Draw A Dinosaur Day website. It doesn't have to be your birthday to participate in the festivities - anybody can submit a picture. Just grab some paper and a pencil, pen, paintbrush, or even your mouse and computer and draw your favorite dinosaur. Then scan it or whatever, and post it to their site between now and February 2nd. Personally, my drawing technique is a bit rusty so I've dug through the archives and found some dinosaur pictures I drew back in the middle of the last century that I'm thinking of uploading. This is the holiday's 4th year.
Sinosauropteryx
Courtesy Chuang Zhao and Lida XingScientists from China and the United Kingdom say they have found hints of color present in the fossils of both an ancient bird called Confuciusornis and a non-avian dinosaur called Sinosauropteryx. Using an electron microscope the researchers detected differently-shaped organelles called melanosomes in the feathers of each creature. Melanosomes contain melanin which determines color in human hair, animal fur, and feathers, but it's the shape of the melanosomes that determine the shade.
"A ginger-haired person would have more spherical melanosomes, and a black-haired or grey-haired person would have more of the sausage-shaped structures," said Mike Benton, professor of paleontology at the University of Bristol, and leader of the study.
Both shapes were found in the remains of Confuciusornis, which lived during the Early Cretaceous period. In the Sinosauropteryx fossil, which dates back to the same time, light and dark bands visible along its tail were determined to be white and ginger in color when its fossilized melanosomes were viewed under the microscope. The presence of melanosomes also confirms that the turkey-sized dinosaur had actual feathers rather than just shredded connective tissue as some scientists have suggested. The research appears in the latest issue of Nature.
Watch an interview with Professor Benton.
SOURCES
University of Bristol page
BBC story
This nifty video from SEEDMAGAZINE.com shows the scale of significant evolutionary events in Earth's 4.6 billion year history by condensing everything into a single minute.
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