Courtesy National Portrait GalleryLast month, on November 22nd, while many people in the country were observing the 50th anniversary of president John F. Kennedy's assassination by shots fired from the Texas School Book Depository, there was another significant event happening that day involving Texas schoolbooks. That same Friday, despite objections and obstructionist tactics by creationists, the Texas Board of Education approved several public school science textbooks that included full coverage of evolution and climate change. The vote came late in the day and although the creationist faction did manage to make the adoption of two biology books contingent on a committee ruling regarding some alleged "flaws" in the text, the Texas Freedom Network (TFN), a watchdog group instrumental in countering the irrational creationist attacks, expects the passage to stand.
“It’s hard to overstate the importance of today’s vote, which is a huge win for science education and public school students in Texas,” said Kathy Miller, TFN's president. “Four years ago this board passed controversial curriculum standards some members hoped would force textbooks to water down instruction on evolution and climate change. But that strategy has failed because publishers refused to lie to students and parents demanded that their children get a 21st-century education based on established, mainstream science.”
Courtesy Mark RyanA new and troubling paper from the Committee on Understanding and Monitoring Abrupt Climate Change and its Impacts predicts possible and somewhat grim outcomes for some of Earth's natural systems from climate change that could rival the extinction event of the non-avian dinosaurs at the end of the Cretaceous Period 65 million years ago.
The abrupt impact could be coming faster than previously expected and would negatively affect human and physical climate systems as well. The document warns that the abruptness of the changes could be unanticipated and could find us unprepared to deal with them
Records of past climate preserved in tree rings, ice cores, and ocean sediments show that the atmosphere contains higher levels of carbon dioxide than it has in a very long time. Carbon emissions from human activity continue to add to this rising concentration. Other activities including deforestation and resource extraction place additional environmental pressures on our climate and other natural systems.
At the end of the Cretaceous, all species of non-avian dinosaurs, along with the megafauna of flying and swimming reptiles were wiped off the face of the Earth. Many dinosaur species showed signs of decline even before the Chicxlub asteroid delivered the final kibosh on their existence.
Dr. James W.C. White, a professor of Geological Sciences and of Environmental Studies at the University of Colorado at Boulder chaired the committee which included more than a dozen earth scientists and ocean researchers from universities in both Canada and the United States, and from the National Academy of Science.
A prepublication copy of the entire 201-page paper is available to read without charge on the National Academies Press page. You can also download it for free although it was a little tricky getting it to my computer.
Courtesy Radiological Society of North AmericaUsing state-of-the-art medical scanning and printing technology, German paleontologists have been able to scan and reconstruct a dinosaur vertebrae that survived a World War II bombing raid that left hundreds of fossils unidentified. Dug out of a clay pit south of Halberstadt, Germany in the early 20th century, the fossil was jacketed in plaster (for protection during transportation from the field) and stored in the basement of the Museum für Naturkunde in Berlin along with numerous other fossils from Halberstadt in southern Germany and another dig site in Tanzania. When the Allies made a bombing raid over Berlin during WWII, a portion of the museum was hit and collapsed, leaving the poorly labeled fossils in one big messy pile of plaster jackets and rubble. Museum workers sorted the jacketed fossils from the rubble but which fossil came from which dig? The labeled plaster jackets gave no clue.
Courtesy Mark RyanModern technology came to the rescue from technicians from the Department of Radiology at Charité Campus Mitte in Berlin. One of the jacketed fossils was first scanned with a CT (computed tomography) scanner - similar to those used to scan and diagnose medical patients. Because the radiation absorption (attenuation) of the fossil differs from that of the surrounding matrix - the rocky material in which the fossil is encased - making it easy to outline and create a digital copy of the fossil. The resulting image was compared to field drawings from the two expeditions and identified as a vertebrae of a Triassic Period prosauropod known as a Plateosaurus. The dataset was entered into a computer, cleaned up a bit, and then fed into a 3D printer where - layer by plastic layer - an exact replica of the hidden and unprepared fossil was "printed" in 3-dimensions.
CT scanning and 3D printing of fossils has been in use for a while now but this is a first time paleontologists have been able to identify and copy a dinosaur bone still encased in a matrix wrapped in a plaster field jacket.
In the past, this couldn't have been done without first cutting open the field jacket and spending long hours of detailed lab preparation - i.e. removing all the matrix from around the fossil. Making copies of fossils usually entails creating molds using rubber or something similar, then filling the void with plaster or other casting materials. Now with 3D printing technology, exact (or scaled) duplicates of important fossils can be created and shared with scientists or schools for study and comparison. The dataset of the scan can serve the same purpose.
Both the cost and size of the technology have been reduced in recent years, making it both affordable and portable for many museums. The following videos show the processes in action. Desktop scanning of dinosaur bones and the printing a dinosaur skull with a simple desktop 3D printer.
With the announcement of the Ultimate Dinosaurs: Giants of Gondwana exhibit comming to the Science Museum of Minnesota, I was thinking back to all the questions I have had regarding dinosaurs.
Courtesy Mark Ryan
Questions like: "Who gets to name Dinosaurs?" "What is this dinosaur named after?" and "What does this name mean?". I thought that I'd take some time here to answer these questions.
Courtesy Mark RyanIt's Earth Science Week and this year's celebration centers around maps and mapping and their importance in geology and other earth sciences. Then on Saturday, October 19th from 1-4pm, the Science Museum of Minnesota is celebrating National Fossil Day with some special fossil-related exhibits throughout the museum. This year's theme is Paleozoic life, which is exactly the types of fossils commonly found in the southern half of Minnesota. Unfortunately, the official National Fossil Day website is closed due to the US government shutdown that continues, but that shouldn't stop anyone from celebrating fossils. Join us Saturday for some fossil fun.
Courtesy Mark RyanA new study appearing in Biology Letters shows that trilobites - everyone's favorite prehistoric water bug - developed an effective survival strategy much earlier than previously thought.
Trilobite fossils from Early Cambrian rock formations in the Canadian Rockies and elsewhere lend evidence that some of the earliest trilobites used enrollment (i.e rolling themselves up into a ball like an armadillo) to protect themselves from predators or the environment. Trilobite fossils found here in Minnesota are several million years younger dating back to the Late Cambrian through Late Ordovician Periods (500 - 430 mya) and are often found enrolled. It was an effective survival strategy.
Trilobites were arthropods, which meant they possessed exoskeletons, segmented bodies and jointed appendages. Their closest extant relative is the horseshoe crab. Trilobite bodies - for the most part - were comprised of a head (cephalon) positioned on a body (thorax) that was divided into three lobes: essentially an axial dividing a left and right pleura, and a tail (pygidium). The mouth (hypostome) was located on the underside. It's thought that most early trilobites were predators and/or scavengers who spent their lives roaming the sea floors looking carcasses, detritus or living prey to feed upon. Most trilobites possessed complex eyes (although some were eyeless). Like other arthropods (e.g. today's lobsters), trilobites would outgrow their exoskeletons, discarding them (molting) as they grew in size or changed shape. Their newly exposed soft skin soon hardened into a new, tough, outer casing. Once hardened, their segmented exoskeletons (composed of calcium carbonate) were ventrally flexible, giving them the ability to roll up into a ball should they need sudden protection from whatever threatened them.
Some early trilobite forms from Middle Cambrian-aged fossils had been viewed as incapable of enrolling but the new research based on much older fossils found in mudstones in the Canadian Rockies in Jasper Park pushes back the origins of the strategy to some of the earliest trilobites to appear in the fossil record (Suborder Olenellus). These appeared 10-20 million years earlier at the very beginnings of the Cambrian Period and show evidence of having already developed the ability to enroll.
Trilobites in some form or another existed across a span of more than 270 million years, a very successful run by any measure. The enrollment strategy certainly contributed to their longevity. Although trilobites were already in decline, the last of their kind were wiped out in the great extinction event that marked the end of the Permian Period and the start of the Triassic. They weren't the only casualty of the extinction: nearly 90 percent of Earth's species were terminated along with them.
Even though trilobites are extinct (they died out in the Permian Mass Extinction along with around 90 percent of Earth's species) they were an extremely successful and adaptable life form. No wonder they remain today a favorite among fossil collectors.
Courtesy WikipediaFilm goers will have the chance to travel through space this weekend with the blockbuster movie "Gravity" hitting the theaters. Its a ficticious story about two American astronauts dealing with disaster during a space shuttle mission.
I've come to expect Hollywood to place loose and easy with actual science when it comes to movies with scientific themes. And then today I stumbled upon this article in Time by Jeffrey Kluger, the co-author, with astronaut Jim Lovell, of Lost Moon: The Perilous Voyage of Apollo 13, which was the basis of the Apollo 13 movie released in 1995.
He applies his extensive space knowledge to fact check what's depicted in the new George Clooney/Sandra Bullock film. Here's his analytical summary: "So, that’s a lot that Gravity gets wrong. But you know what? So what? The shuttle, space station and spacesuits are painstakingly recreated; the physics of moving about in space—thrusts requiring counterthrusts, spins requiring counterspins, the hideous reality that if you do go spiraling off into the void your rotation never, never stops—are all simulated beautifully, scarily and accurately."
Click on the link above to get detailed analysis of what's scientifically right and wrong with Gravity.
Have you seen the film? What do you think about its accuracy in portraying the science of living and traveling in space?
Courtesy Mark RyanOver the past couple years, Science Buzz has posted several stories (here and here) about the humongous patches of garbage and plastic debris found floating in the world's oceans. It's a serious problem and one that should raise red flags for anyone concerned with the Earth's environment. But even more troubling is the recent news that plastic particles have now been found in all five of the Great Lakes lining the border of the USA and Canada. Unlike the large globs of plastic clogging areas of the ocean, the plastics polluting the Great Lakes are microscopic particles detectable only in a microscope. But they're no less disturbing.
A team of researchers led by Dr. Sherri “Sam” Mason, professor of chemistry at SUNY-Fredonia has been gathering water samples and reported finding high concentrations of plastic particles in the chain of freshwater lakes. One of the researchers involved is environmental chemist Lorena Rios-Mendoza from University of Wisconsin-Superior. Both she and Mason have studied the Great Trash Island (aka Trashlantis) in the Pacific Ocean but has now turned their attention to the Great Lakes.
Most of the plastic found in the water is visible only under a microscope, but has been found in all five of the Great Lakes, both in the water column, and in lake sediment. The amount of micro-plastic varies between lakes with Lake Erie - the shallowest and smallest by water volume - containing the largest ratio and Lake Superior - the largest and most voluminous - a much smaller ratio. But it doesn't matter; the point is that we're polluting some of our important sources of fresh water with plastic.
It's thought that cosmetics with could one of the sources, since the industry relies heavily on using micro-beads in its products. These tiny plastic particles used on our faces, skin, and teeth, eventually get washed off into the water supply where they're too small to get filtered out. But cosmetics certainly aren't the only source.
Courtesy tedxgp2Think of the ungodly amount of plastic material we use and discard every year. Surprisingly, only about five percent of the bags, bottles, cups, electronics, etc. get recycled; most plastic trash ends up in landfills where it slowly degrades and eventually finds its way into the world's favorite garbage dump: the oceans.
“We have no idea how long some of these plastics stay in the ocean, could be more than 40 years,” Rios-Mendoza said. She also worries if organic toxins in the water can attach themselves to the tiny plastic particles, and end up in the food chain. In this regard, Rios-Mendoza has been sampling Great Lake fish to see if such toxic particles are present in their guts.
It's important to remember that only 3 percent of the world's water is freshwater and the five Great Lakes - Superior, Huron, Michigan, Ontario, and Erie - together contain 20 percent of that freshwater. That's a large portion of a relatively scarce and essential life ingredient. Last fall, I posted an interesting graphic that illustrates nicely Earth's total water supply versus fresh water and puts things in perspective.
Courtesy Mark RyanRios-Mendoza and Mason have been collaborating with a research and education group called 5Gyres Institute that monitors and studies garbage patches found in five subtropical gyres in the world's oceans. Rio-Mendoza presented a preliminary study of their work on the Great Lakes at a recent meeting of the American Chemical Society. The team's future studies involve pinpointing the sources of plastic pollution and acquiring a better understanding of how plastics degrade in the environment.
"We all need to become aware of how much plastic we use in our lives and avoid using single-use products. Don’t buy water in plastic bottles or cosmetic products with micro beads. Bring re-usable bags to the store with you. Simple things like this make a big difference, but it’s also important to keep talking about this issue and raising awareness about how it affects the Great Lakes and the world’s oceans.” --- Dr. Sherri Mason“
By the way, here in Minnesota, and situated at the western tip of Lake Superior, the city of Duluth was recently proclaimed to have the best tasting drinking water in the state. By best-tasting, I'm assuming they mean it has no taste whatsoever since water is described as a colorless, tasteless liquid. Whatever the case, I always thought Duluth's drinking water was the best while growing up there (my grandparents lived in a Twin Cities' suburb and I never liked the taste of their softener-treated water).
In another water-related story, it's estimated that life on Earth can survive for at least another 1.75 billion years until we move out of the habitable zone and our oceans (and other water sources) will evaporate in the increased heat. So it's probably best that we take care of what water we have - it needs to sustain us for a long time.
Courtesy ap2il via FlickrOne of the strangest creatures to emerge from the famed Burgess Shale in the mountains of British Columbia, is the rightly named Hallucigenia, a strange spiky, wormlike creature that once scuttled across the Cambrian sea bottom more than 500 million years ago. Originally considered a totally unique (and baffling) creature, Hallucigenia has now been linked to other similar-aged wormlike creatures found around the world.
Hallucigenia first came to light in 1909 after Charles Doolitle Walcott, an expert in trilobites and secretary of the Smithsonian Institute, discovered a Lagerstätte in the mountains of British Columbia that was unlike any other found before.
Courtesy Mark RyanLocated in Yoho National Park on a steep slope between Mount Field and Wapta peak above the railroad town of Field, B.C., Walcott's quarry produced some of the strangest creatures - many of them soft-bodied and rarely found in the fossil record. The rock section, previously known as the Stephens Formation became known as the Burgess Shale, after nearby Burgess Pass. In the years following the discovery, Walcott and other scientists studied the strange fossils in an effort to decipher them and the environment in which they had lived and died.
Because of the high degree of preservation, the creatures that made the fossils were most likely buried suddenly in some sort of giant underwater mudslide that quickly entombed an entire marine community in an anoxic environment where decomposition was stifled. A perfect environment for preserving the soft-bodied tissue.
Courtesy Mark RyanSome of the Burgess Shale denizens appeared to be of completely new and unknown phyla with bizarre and unfamiliar body plans and no known descendents in the modern age. Hallucigenia certainly led the pack in this department. The tiny strangely constructed worm was only about an inch in length and confounded Walcott and other scientists for more than a century. They couldn''t even say for sure which side was up or down. Early Hallucigenia fossils showed a row of seven tentacles along one side. The opposite side contained seven sets of stiff spikes that were interpreted to be legs. A truly bizarre, aptly named freak-show creature that would be right at home in your average nightmare.
New evidence can often turn an old idea on its ear - or in this case, on its back. Recent scrutiny of newer, better-defined Hallucigenia fossils has revealed another set of "tentacles", leading scientist to realize they had Hallucigenia all flipped around. What they once thought was its top side was actually its bottom. Its dorsal "tentacles" were actually its legs. And its spiky "legs" belonged on its back, probably to serve as protection against predators.
This information along with a new study published in Proceedings of the Royal Society B now places Hallucigenia within a group of other worm-like creatures whose fossils are found around the world, including China, Canada, Great Britain, and Australia. It also links it to a living group - Onychophora - the velvet worms that mostly inhabit the tropical forests of the Southern Hemisphere.
"They may not be exactly the same species, but they are all probably related to the same group of worm-like creature that we call lobopods," said Dr. Jean-Bernard Caron, curator of invertebrate paleontology at the Royal Ontario Museum and the study's lead researcher. Caron is an expert in Burgess Shale fossils and his study of Hallucigenia and other fossils from the formation continues to glean new knowledge about the strange creatures that existed in the so-called Cambrian Explosion. Check out Caron's Burgess Shale website. It's full of great information about the quarry and the incredible fossils found there.
Courtesy Mark RyanWalcott's Burgess Shale quarry has been designated a World Heritage site. The only way to visit it (or the fossil fields on nearby Mt. Stephen) is through guided hikes led by either Parks Canada or The Burgess Shale Geoscience Foundation. The 10 hour round-trip hike (rated moderate to difficult) takes participants up 2500 feet in elevation to Mt. Fields and requires reservations and a deposit. Fossil collecting is prohibited but the views are said to be spectacular.
SOURCE and LINKS
The Province story
The Burgess Shale at Smithsonian website
Dr. Caron's Burgess Shale website
Parks Canada Burgess Shale info
A long-buried, underwater forest of Cypress trees was recently discovered in the Gulf of Mexico. The forest, estimated to be about 50,000 years old, was once buried under tons of sediment, heading toward possible fossilization, until the natural forces (most likely 2005's Hurricane Katrina) riled up the Gulf Coast waters and uncovered it again. Hundreds of stumps and fallen logs - some huge - covering 1.3 square kilometers can now be seen in 60 feet of water, 10 miles off the coast of Alabama. The Cypress forest once populated the area around the Mobile-Tensaw Delta when the Gulf's coastline was farther south, and the water level was 120 feet lower than it is today. As the climate began to warm, rising sea levels eventually drowned the forest. The trees all died but oxidation and decomposition were halted as a constant rain of delta silt covered the forest for thousands of years. When cut, the well-preserved wood still smells as fresh as living Cypress, but now that the forest has been uncovered again, wood-boring marine animals are back at work tearing it down.