Courtesy Mark RyanA rescue effort is underway right now in St. Paul where three children are reported to have gotten stranded in Lilydale Regional Park. A helicopter and several rescue units are on site. Two children has already been recovered and taken to hospital but one child is still missing. The children were part of a group of 4th-graders on a field trip from St. Louis Park.
Lilydale is a popular fossil collecting site for school field trips and others but the Decorah shale in the quarries where most of the fossils are found can become very treacherous in wet weather. The crumbly shale reconstitutes into a very thick, slippery muck when it rains making the steep quarry walls very unstable. Three inches of rain have fallen in the Metro area over the past few days.
A firefighter reportedly sustained injuries to his head from a falling rock during one of the rescues. Let's hope everything else turns out okay.
Courtesy Fancy Horse (underwater background)The genome of the coelacanth, the world's best known living fossil, has been sequenced by an international team of researchers and is revealing something scientists already suspected: that the primitive-looking fish has evolved more slowly than most other organisms. The coelacanth is related to the lungfish and several extinct Devonian fish species that are considered precursors to land dwelling tetrapods. Kerstin Lindblad-Toh is senior author of the study which appeared recently in the science journal Nature.
"We often talk about how species have changed over time, but there are still a few places on Earth where organisms don't have to change, and this is one of them," Lindblad-Toh said. "Coelacanths are likely very specialized to such a specific, non-changing, extreme environment -- it is ideally suited to the deep sea just the way it is."
Lindblad-Toh is scientific director of the Broad Institute's vertebrate genome biology group in Cambridge, Massachusetts, which did the genome research. The institute is linked to both MIT and Harvard.
The genetic map, which involved sequencing some 3 billion letters of DNA, also showed (via RNA content) that tetrapods - four-legged land dwelling animals - though related to both coelacanths and lungfish, are more closely related to lungfish and followed that line rather than that of the coelacanth. We humans also branched off that same line. The genome of a lungfish is composed of over 100 billion DNA letters, making it a much more difficult task to sequence, so for the time being, the coelacanth's DNA makes for a reasonable alternative for study.
"This is just the beginning of many analyses on what the coelacanth can teach us about the emergence of land vertebrates, including humans, and, combined with modern empirical approaches, can lend insights into the mechanisms that have contributed to major evolutionary innovations," said professor Chris Amemiya at the University of Washington, and the paper's co-author.
Courtesy photo by Haplochromis via Wikipedia Creative CommonsWhen Louis Agassiz named the first fossil coelacanth back in 1836, the Swiss paleontologist probably never imagined that a nearly identical descendent of the primitively constructed Devonian-aged fish would one day be found still inhabiting the world's oceans. The coelacanth was thought to have gone extinct along with the non-avian dinosaurs at the end of the Cretaceous period. None have been found in the fossil record after that time, but two extant species are known today. The first specimen Latimeria chalumnae was netted off the coast of South Africa in 1938, near the Chalumnae river and retrieved by East London Museum curator Marjorie Courtenay-Latimer who discovered what she called "the most beautiful fish I'd ever seen" in the catch of local fisherman, Henrik Goosen. Since then several more coelacanths have been caught, including the Indonesian species, Latimeria menadoensis, from the Indian Ocean.
The remarkable prehistoric throw-back, sometimes referred to as "old four legs" because of its leg-like fins, hasn't changed much in its 350 million year history. A member of the clade of lobe-finned fishes called Sarcopterygii, coelacanths retain primitive characteristics such a notochord, a hollow fluid-filled tube made of cartilage that underlies the spine over the length of its body. In all other vertebrates, the notochord is an anatomical structure that appears briefly only during the embryonic stage but not in adults. Not so with the coelacanth. It also possesses, primitive shark-like intestines, a linear heart, and tightly-woven armor-like scales (known as cosmoid) that are only found on extinct species of fish. The coelacanth's brain case contains only 1.5 percent gray matter - the other 98.5 percent of space is filled with fat. The other end of the coelacanth body begins to taper before expanding into a strange, three-lobed tail. Its most notable features are its lobed pectoral and pelvic fins that are structured with bones that look like toes, and move in an alternating tetrapod manner. An electroreceptive rostal organ located in its snout is used to detect prey, and the coelacanth is the only living animal that can unhinge a section of the its cranium to increase the gape of its mouth, enabling it to consume larger prey.
The blue or brown, white-speckled coelacanths prefer deep-water environments, and can reach six and a half feet in length and weigh upwards to 175 pounds. For some reason no living coelacanth has managed to survive more than a single day in captivity. With a dwindling population estimated at only 500-1000 individuals, the coelacanth was declared an endangered species in 1989.
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Courtesy Mark RyanDo you like fossils? Do you like to draw or take photographs? Then you should know that the 4th annual National Fossil Day Art and Photography Contest is now accepting submissions. The contest runs until next autumn (submissions must be postmarked by October 4th) when judges will select the winning entries. It's all part of the many celebrations of fossils that take place across the country on and around the official National Fossil Day on October 16, 2013. The celebration is a combined effort by the National Park Service along with several federal and state agencies, and earth science related organizations.
There are four age categories: ages 5-8, 9-13, 14-18, and for us old-timers, 19 and up. You can find all the information you need here on the official National Fossil Day contest site.
This year's contest theme is: "Your nomination for our National Fossil". Maybe you think it's should be a dinosaur, or a trilobite, or one of the famous fossil fish found in the Green River shales of the western USA? Whatever you think, get out your pencils, pens, paints, or cameras and make your case for our national fossil.
By the way, Minnesota is one of 10 states in the union lacking an official state fossil. That needs to be remedied. Do you have a favorite fossil found in Minnesota? Maybe you found one yourself at one of the fossil collecting sites around the Twin Cities. If so, let us know in the comments.
Courtesy Peabody Museum of Natural History, Yale UniversityOn this day in 1877, railroad worker William Harlow Reed came over a ridge-top with the remains of a freshly killed antelope slung over his shoulder, and spotted huge fossilized bones exposed on the side of the steep bluff located a half-mile south of Como Station, a desolate railroad stop on the High Plains of Wyoming. It was a discovery that would forever change his life.
Reed and station master, William Carlin, began collecting up as much as they could, dreaming of money and employment other than railroad work. They waited several months before announcing the discovery in a letter to Yale professor Othniel C. Marsh, at the time one of America's prominent paleontologists. When a crate of bones - along with the guarantee of many more - arrived at Yale, Marsh realized they were dinosaur remains and hired both men to excavate and send him as much as they could, and to keep out any interlopers to his claim. Marsh knew if he could keep it secret - at least for a short time - the fossils at Como Bluff could give him a huge advantage in his rivalry with Philadelphia paleontologist, Edward Drinker Cope, and their notorious Bone Wars.
Courtesy Mark RyanThe dinosaur-rich strata at Como Bluff (the Morrison Formation) are found in the exposed flanks of an anticline (an upward fold), the center of which has been carved out by erosion [see diagram]. All three periods of the Mesozoic Era (Triassic, Jurassic, Cretaceous) are represented in the rock layers found there. Besides dinosaurs, fossils of fish, crocodiles, flying and swimming reptiles have also been found there. A significant number of important Late Jurassic mammalian fossils were discovered and collected by William Reed from Quarry 9 on the east end of Como. Reed also discovered and removed the great Brontosaurus excelsus skeleton that stands today in Yale's Peabody Museum.
Courtesy Peabody Museum of Natural History, Yale UniversityIn the years following its discovery hundreds of tons of dinosaur remains quarried at Como Bluff were shipped to Yale and other institutions pushing America into the forefront of vertebrate paleontology, and heavily influencing how museums would be constructed throughout the world.
Courtesy Mark RyanThe dinosaur halls at the American Museum of Natural History have several mounted specimens found at Como Bluff as does the Smithsonian in our nation's capitol. Well-known genera like Allosaurus, Diplodocus, Apatosaurus, Stegosaurus and Camptosaurus are just a few of the dinosaurs pulled from the mudstones and sandstones at Como Bluff. In the early 20th century it was thought that Como had exhausted its supply of dinosaur remains and exploration there for the most part tapered off for several decades. But in recent years, paleontologist Robert Bakker has been re-examining the quarries and uncovering additional secrets still buried in the Jurassic bluffs at Como.
Courtesy Mark RyanWilliam Reed worked for Marsh for several more years and the two men remained friends until the Yale professor's death in 1899. Reed continued in the field of paleontology, working independently, and for a time with the American Museum of Natural History in New York, and the Carnegie Museum in Pittsburgh. He finished out his career as a popular geology professor and museum curator at the University of Wyoming, just sixty miles from Como Bluff, the great dinosaur graveyard that changed not only the course his life but also that of American paleontology.
Como Bluff was added to the National Register of Historic Places in 1973. It's also been designated as one of Wyoming's National Natural Landmarks by the National Park Service.
Courtesy Mark RyanHey kids! This coming Wednesday - January 30th - is my birthday. And even more exciting, it’s once again Draw A Dinosaur Day! I used to love drawing dinosaurs as a kid so I think it really cool that the two events fall on the same date each year. What’s so special about Draw A Dinosaur Day? It’s not really complicated – it’s just a day to draw your favorite dinosaur and submit it to the official DADD website. Simple, huh?
Several years ago, Mr. Todd H. Page, the brains behind DADD, thought it would be “a fun way to get everyone to do something creative and silly.” He got that right. Just look at some previous submissions.
This year will be the 7th annual Draw A Dinosaur Day. So, in the next few days start to figure out which dinosaur you want to draw and then, on January 30th get out your pens, pencils, crayons or whatever and draw a dinosaur. When you’re finished, upload your masterpiece to the DADD page!
That’s all I want for my birthday.
Courtesy Jordi Payà via FlickrPaleo-blogger Brian Switek has written an interesting and lengthy article recounting the recent attempt to auction off a stolen Tarborsaurus bataar skeleton. Professional paleontologists and other concerned parties complained that the illegal dinosaur's remains had come from - and by law belonged to - the country of Mongolia. A last minute court order stopped the auction just as the Tarborsaurus (a relative of the Tyrannosaurus rex) was on the block and already receiving bids. Switek, who blogs about dinosaurs on the National Geographic magazine’s Phenomena website writes how the black-market fossil trade deprives institutions of both funds and important scientific knowledge. It does so by creating a commercial market that tends to overly inflate the price of rare fossils beyond the reach of most non-profit institutions, and removes rare specimens from scientific study and public view.
Courtesy Public domain via WikipediaThis clever greeting card was created over 90 years ago by paleo-artist, Charles R. Knight. I thought it'd be a great way to wish all readers of Science Buzz a very Happy New Year!
I'm a big fan of Knight's work. Many of his best prehistoric-themed murals can be seen at the Field Museum in Chicago. Additional paintings can be found at colleges, libraries and other museums in the US, including the American Museum of Natural History in New York, and the Natural History Museum in Los Angeles.
Courtesy Mark RyanWe're lucky to have one here at the Science Museum of Minnesota. It's a large original painting of a Stegosaurus done by Knight in 1930 (see photo). It hangs in the Dinosaurs and Fossil gallery next to the Camptosaurus exhibit. The painting was the template for the mosaic that graces the entrance to the Reptile House at the National Zoo in Washington, D.C.
Thanksgiving is upon us, and once again, the centerpiece of the traditional holiday meal is a dinosaur. Eat up and 'Happy Thanksgiving'!
Courtesy Mark RyanDinosaur expert, Jack Horner, was in the Twin Cities this week for a very interesting talk at Macalester College on his investigations into creating a dinosaur through manipulation of the chicken genome. His research involves switching on evolutionary carryover genes that lay dormant in the chicken's gene sequence, such as teeth or a long reptilian tail. He's had some success but is still a long way off from unleashing a Chickenosaurus on the world. When asked why chickens when a bigger bird like an ostrich would make for a cooler and much larger dinosaur, the Museum of the Rockies paleontologist answered that the chicken genome already exists, chickens are cheap, and there are simply just more of them. Afterwards, Horner signed copies of his book, How to Build a Dinosaur for students and the public.
Paleontologists from the University of Calgary and the Royal Tyrrell Museum of Palaeontology have announced the discovery of the first ever evidence of feathered dinosaurs discovered in the Western Hemisphere. Until now, all previous feathered dinosaur evidence has come from fine silt lagoon and lake deposits found in Germany and China. The remarkable Canadian fossils come from 75 million year-old river deposits found in the badlands of Alberta. The feathered remains belong to a type of dinosaur known as ornithomimid, or bird-mimic (apropos - yes?). News of the discovery is reported at the online journal Phys.org.