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Found 12 results

  1. Extinction of Mainland and Island Mammoth Populations in Alaska 6,000 Years Ago, Royal Tyrrell Museum Speaker Series 2017 Dr. Duane Froese, University of Alberta, presents new research on the extinction of mammoths and other megafauna from Arctic North America and the causes of the final extinction of a population on St. Paul Island, Alaska, about 6000 years ago. Some of the papers referenced in the talk are: Graham, R.W., Belmecheri, S., Choy, K., Culleton, B.J., Davies, L.J., Froese, D., Heintzman, P.D., Hritz, C., Kapp, J.D., Newsom, L.A. and Rawcliffe, R., 2016. Timing and causes of mid-Holocene mammoth extinction on St. Paul Island, Alaska. Proceedings of the National Academy of Sciences, p. 9310–9314. Guthrie, R.D., 2006. New carbon dates link climatic change with human colonization and Pleistocene extinctions. Nature, 441(7090), pp. 207-209. Palkopoulou, E., Dalén, L., Lister, A.M., Vartanyan, S., Sablin, M., Sher, A., Edmark, V.N., Brandström, M.D., Germonpré, M., Barnes, I. and Thomas, J.A., 2013, November. Holarctic genetic structure and range dynamics in the woolly mammoth. In Proc. R. Soc. B (Vol. 280, No. 1770, 9 pp.) The Royal Society. Yours, Paul H.
  2. These are a few of the pdf files (and a few Microsoft Word documents) that I've accumulated in my web browsing. MOST of these are hyperlinked to their source. If you want one that is not hyperlinked or if the link isn't working, e-mail me at joegallo1954@gmail.com and I'll be happy to send it to you. Please note that this list will be updated continuously as I find more available resources. All of these files are freely available on the Internet so there should be no copyright issues. Articles with author names in RED are new additions since March 30, 2017. General Dinosaurs Agnolin, F.L., et al. (2010). A reappraisal of the Cretaceous non-avian dinosaur faunas from Australia and New Zealand: evidence for their Gondwanan affinities. Journal of Systematic Palaeontology, Vol.8, Issue 2. Antunes, M.T. and O. Mateus (2003). Dinosaurs of Portugal. C.R. Palevol,2. Averianov, A.O. and P.P. Skutschas (2009). Additions to the Early Cretaceous Dinosaur Fauna of Transbaikalia, Eastern Russia. Proceedings of the Zoological Institute RAS, Vol.313, Number 4. Barrett, P.M. and E.J. Rayfield (2006). Ecological and evolutionary implications of dinosaur feeding behaviour. Trends in Ecology and Evolution, Vol.21, Number 4. Bates, K.T., et al. (2009). Estimating Mass Properties of Dinosaurs Using Laser Imaging and 3-D Computer Modelling. PLoS ONE, 4(2). (Read on-line or download a copy.) Benton, M.J. (2006). The Origin of the Dinosaurs. In: Actas de las III Jornadas sobre Dinosaurios y su Entorno. Colectivo Arqueologico-Paleontologico Salense (ed.), Salas de los Infantes, Burgos, Espana. Bonaparte, J.F. (1986). The Dinosaurs (Carnosaurs, Allosaurids, Sauropods, Cetiosaurids) of the Middle Jurassic of Cerro Condor (Chubut, Argentina). Annales de Paleotologie (Vert.-Invert.), Vol.72, Number 4. Botelho, J.F., et al. (2014). New Developmental Evidence Clarifies the Evolution of Wrist Bones in the Dinosaur-Bird Transition. PLoS ONE, 12(9). Brusatte, S.L., et al. (2008). Superiority, Competition and Opportunism in the Evolutionary Radiation of Dinosaurs. Science, Vol.321. Brusatte, S.L., et al. (2008). The first 50 Myr of dinosaur evolution: macroevolutionary pattern and morphological disparity. Biol.Lett., 4. Carpenter, K. (1982). Baby dinosaurs from the Late Cretaceous Lance and hell Creek formations and a description of a new species of theropod. Contributions to Geology, University of Wyoming, Vol.20, Number 2. Claessens, L.P.A.M. (2004). Dinosaur Gastralia; Origin, Morphology, and Function. Journal of Vertebrate Paleontology, 24(1). Chapman, R.E., et al. (1997). Sexual Dimorphism in Dinosaurs. Dinofest International Proceedings. Colbert, E.H. (1962). The Weights of Dinosaurs. American Museum Novitates, Number 2076. Dalla Vecchia, F.M. (2003). Observations on the Presence of Plant-Eating Dinosaurs in an Oceanic Carbonate Platform. Natura Nascosta, Number 27. Dalla Vecchia, F.M. (1995). Second Record of a Site with Dinosaur Skeletal Remains in Libya (Northern Africa). Natura Nascosta, Number 11. Davis, M. (2014). Census of dinosaur skin reveals lithology may not be the most important factor in increased preservation of hadrosaurid skin. Acta Palaeontologica Polonica, 59(3). ######, Z., S. Zhou and Y. Zhang (1983). Dinosaurs from the Jurassic of Sichuan. Palaeontologica Sinica, Whole Number 162, New Series C, Number 23. Dorr, J.A. (1985). Newfound Early Cretaceous Dinosaurs and Other Fossils in Southeastern Idaho and Westernmost Wyoming. Contributions from the Museum of Paleontology - The University of Michigan, Vol.27, Number 3. Feduccia, A. (2002). Birds are Dinosaurs: Simple Answer to a Complex Problem. The Auk, 119(4). Gauthier, J. and K. de Quiroz (2001). Feathered dinosaurs, flying dinosaurs, crown dinosaurs, and the name "Aves". In: New Perspectives on the Origin and Early Evolution of Birds: Proceedings of the International Symposium in Honor of John H. Ostrom. Gauthier, J. and L.F. Gall (eds.), Peabody Museum of Natural History. Gillooly, J.F., A.P. Allen and E.L. Charnov (2006). Dinosaur Fossils Predict Body Temperatures. PLoS Biology, 4(8). Gilmore, C.W. (1933). Two New Dinosaurian Reptiles from Mongolia with Notes on Some Fragmentary Specimens. American Museum Novitates, Number 679. Hocknull, S.A., et al. (2009). New Mid-Cretaceous (Latest Albian) Dinosaurs from Winton, Queensland, Australia. PLoS ONE, 4(7). (Read on-line or download a copy.) Holliday, C.M. and L.M. Witmer (2008). Cranial Kinesis in Dinosaurs: Intracranial Joints, Protractor Muscles, and Their Significance for Cranial Evolution and Function in Diapsids. Journal of Vertebrate Paleontology, 28(4). Holtz, T.R. and M.K. Brett-Surman (1997). The Osteology of the Dinosaurs. In: The Complete Dinosaur. Farlow, J.O. and M.K. Brett-Surman (eds.). Hone, D.W.E., D. Naish and I.C. Cuthill (2011). Does mutual sexual selection explain the evolution of head crests in pterosaurs and dinosaurs? Lethaia. Jennings, D.S. and S.T. Hasiotis (2006). Taphonomic analysis of a Dinosaur Feeding Site Using Geographic Information System (GIS), Morrison Formation, Southern Bighorn Basin, Wyoming, USA. Palaios, Vol.21. Langer, M.C. and M.J. Benton (2006). Early Dinosaurs: a Phylogenetic Study. Journal of Systematic Palaeontology, 4(4). Lee, Y-N. (2003). Dinosaur Bones and Eggs in South Korea. Memoir of the Fukui Prefectural Dinosaur Museum, 2. Liggett, G.A. (2005). A review of the dinosaurs from Kansas. Transactions of the Kansas Academy of Science, Vol.108, Numbers 1/2. Lucas, S.G., A.B. Heckert and R.M. Sullivan (2000). Cretaceous Dinosaurs in New Mexico. In: Dinosaurs of New Mexico, Lucas, S.G. and A.B. Heckert (eds.), New Mexico Museum of Natural History and Science, Bulletin Number 17. Mateus, O. (2006). Late Jurassic Dinosaurs from the Morrison Formation (USA), the Lourinha and Alcobaca Formations (Portugal), and the Tendaguru Beds (Tanzania): A Comparison. In: Paleontology and Geology of the Upper Jurassic Morrison Formation. Foster, J.R. and S.G. Lucas (eds.), New Mexico Museum of Natural History and Science, Bulletin 36. Nesbitt, S.J., R.B. Irmis and W.G. Parker (2007). A Critical Re-Evaluation of the Late Triassic Dinosaur Taxa of North America. Journal of Systematic Palaeontology, 5(2). Nesbitt, S.J., et al. (2009). Hindlimb Osteology an Distribution of Basal Dinosauromorphs from the Late Triassic of North America. Journal of Vertebrate Paleontology, 29(2). Noto, C.R. and A. Grossman (2010). Broad-Scale Patterns of Late Jurassic Dinosaur Paleoecology. PLoS ONE, 5(9). (Read on-line or download a copy.) Padian, K. and J.R. Horner (2011). The evolution of 'bizarre structures' in dinosaurs: biomechanics, sexual selection or species recognition? Journal of Zoology, 283. Park, E-J., S-Y. Yang and P.J. Currie (2000). Early Cretaceous Dinosaur Teeth of Korea. Paleont.Soc. Korea, Special Publication Number 4. Pontzer, H., V. Allen and J.R. Hutchinson (2009). Biomechanics of Running Indicates Endothermy in Bipedal Dinosaurs. PLoS ONE, 4(11). (Read on-line or download a copy.) Rees, P.M., et al. (2004). Late Jurassic Climates, Vegetation and Dinosaur Distributions. The Journal of Geology, Vol.112. Osborn, H.F. (1923). Two Lower Cretaceous Dinosaurs of Mongolia. American Museum Novitates, Number 95. Rogers, C.S., et al. (2015). The Chinese Pompeii? Death and destruction of dinosaurs in the Early Cretaceous of Lujiatun, NE China. Palaeogeography, Palaeoclimatology, Palaeoecology, 427. Sankey, J.T. (2001). Late Campanian Southern Dinosaurs, Aguja Formation, Big Bend, Texas. J. Paleont., 75(1). Sankey, J.T. Faunal Composition and Significance of High Diversity, Mixed Bonebeds Containing Agujaceratops mariscalensis and other Dinosaurs, Aguja Formation (Upper Cretaceous), Big Bend, Texas. In: New Perspectives on Horned Dinosaurs. Ryan, M., B. Chinnery-Allgeier and D. Eberth (eds.), Indiana University Press, Bloomington. Smith, N.D., et al. (2007). The Dinosaurs of the Early Jurassic Hanson Formation of the Central Transantarctic Mountains: Phylogenetic Review and Synthesis. U.S. Geological Survey and The National Academies, Short Research Paper 003. Sullivan, R.M. (2006). The Shape of Mesozoic Dinosaur Richness: A Reassessment. In: Late Cretaceous vertebrates from the Western Interior. Lucas, S.G. and R.M. Sullivan (eds.), New Mexico Museum of Natural History and Science, Bulletin 35. Varricchio, D.J. (1995). Taphonomy of Jack's Birthday Site, a diverse dinosaur bonebed from the Upper Cretaceous Two Medicine Formation of Montana. Palaeogeography, Palaeoclimatology, Palaeoecology, 114. Wang, Q., X. Wang and Z. Zhao (2010). Recent Progress in the Study of Dinosaur Eggs in China. Dinosaurs, Vol.24, Number 2. Weishampel, D. (2006). Another Look at the Dinosaurs of the East Coast of North America. In: Actas de las III Jornadas sobre Dinosaurios y su Entorno. Colectivo Arqueologico-Paleontologico Salense (ed.). Weishampel, D., et al. (2002). New Early Cretaceous Dinosaur Remains, Including Possible Ceratopsians, from the Wayan Formation of Eastern Idaho. In: And Whereas...Papers on the Vertebrate Paleontology of Idaho Honoring John A. White. Volume 2. W.A. Akersten, et al. (eds.), Idaho Museum of Natural History Occasional Paper 37. Wilborn. B.K. (2001). Two New Dinosaur Bonebeds from the Late Jurassic Morrison Formation, Bighorn Basin, WY: An Analysis of the Paleontology and Stratigraphy. Masters Thesis - Virginia Polytechnic Institute and State University. Woodward, H.N., et al. (2011). Growth Dynamics of Australia's Polar Dinosaurs. PLoS ONE, 6(8). (Read on-line or download a copy.) Zhang, F., et al. (2010). Fossilized melanosomes and the colour of Cretaceous dinosaurs and birds. Nature, Vol.463/25. (Thanks to xonenine for finding this one!) Dinosaur Extinctions Archibald, J.D. and N. MacLeod (2007). Dinosaurs, Extinction Theories For. In: Encyclopedia of Biodiversity, Elsevier Inc. Archibald, J.D. and D.E. Fastovsky (2004). Dinosaur Extinction. In: The Dinosauria. Weishampel, D.B., P. Dodson and H. Osmolska (eds.), University of California Press. Buffetaut, E. (2004). Polar dinosaurs and the question of dinosaur extinction: a brief review. Palaeogeography, Palaeoclimatology, Palaeoecology, 214. Casadevall, A. (2005). Fungal virulence, vertebrate endothermy, and dinosaur extinction: is there a connection? Fungal Genetics and Biology, 42. Fastovsky, D.E. and P.M. Sheehan (2005). The Extinction of Dinosaurs in North America. GSA Today, Vol.15, Number 3. Galbrun, B. (1997). Did the European dinosaurs disappear before the K-T event? Magnetostratigraphic evidence. Earth and Planetary Science Letters, 148. Keller, G., A. Sahni and S. Bajpai (2009). Deccan volcanism, the KT mass extinction and dinosaurs. J.Biosci., 34. Krassilov, V.A. (1981). Changes of Mesozoic Vegetation and the Extinction of Dinosaurs. Palaeogeography, Palaeoclimatology, Palaeoecology, 34. Lopez-Martinez, N., et al. (2000). New dinosaur sites correlated with Upper Maastrichtian pelagic deposits in the Spanish Pyrenees: implications for the dinosaur extinction pattern in Europe. Lyson, T.R., et al. (2011). Dinosaur extinction: closing the '3 m gap'. Biology Letters, 7. Sakamoto, M., M.J. Benton and C. Venditti (2016). Dinosaurs in decline tens of millions of years before their final extinction. PNAS, Vol.113, Number 18. Williams, M.E. (1994). Catastrophic versus Noncatastrophic Extinction of the Dinosaurs: Testing, Falsifiability, and the Burden of Proof. Journal of Paleontology, Vol.68, Number 2. Zhao, Z., et al. (2002). A possible causal relationship between extinction of dinosaurs and K/T iridium enrichment in the Nanxiong Basin, South China: evidence from dinosaur eggshells. Palaeogeography, Palaeoclimatology, Palaeoecology, 178. Paleocene Dinosaurs? The Debate in Chronological Order Fassett, J.E., L.M. Heaman and A. Simonetti (2012). Direct U-Pb dating of Cretaceous and Paleocene dinosaur bones, San Juan Basin, New Mexico: REPLY. Geology, Vol.40 (Forum). Ludwig, K.R. (2012). Direct U-Pb dating of Cretaceous and Paleocene dinosaur bones, San Juan Basin, New Mexico: COMMENT. Geology, Vol.40 (Forum). Fassett, J.E., L.M. Heaman and A. Simonietti (2012). Direct U-Pb dating of Cretaceous and Paleocene dinosaur bones, San Juan Basin, New Mexico: REPLY. Geology, Vol.40 (Forum). Renne, P.R. and M.B. Goodwin (2012). Direct U-Pb dating of Cretaceous and Paleocene dinosaur bones, San Juan Basin, New Mexico: COMMENT. Geology, Vol.40 (Forum). Koenig, A.E., et al. (2012). Direct U-Pb dating of Cretaceous and Paleocene dinosaur bones, San Juan Basin, New Mexico: COMMENT. Geology, 40 (Forum). Fassett, J.E., L.M. Heaman and A. Simonetti (2011). Direct U-Pb dating of Cretaceous and Paleocene dinosaur bones, San Juan Basin, New Mexico. Geology, Vol.39. Clyde, W.C., et al. (2010). New Paleomagnetic and Stable-Isotope Results from the Nanxiong Basin, China: Implications for the K/T Boundary and the Timing of Paleocene Mammalian Turnover. The Journal of Geology, Vol.118. Fassett, J.E. (2009). Response to Critique by Lucas, et al. (2009) of Paper by Fassett (2009) Documenting Paleocene Dinosaurs in the San Juan Basin. Palaeontologia Electronica, Vol.12, Issue 2. Lucas, S.G., et al. (2009). No Definitive Evidence of Paleocene Dinosaurs in the San Juan Basin. Palaeontologia Electronica, Vol.12, Issue 2. Fassett, J.E. (2009). New Geochronologic and Stratigraphic Evidence Confirms the Paleocene Age of the Dinosaur-Bearing Ojo Alamo Sandstone and Animas Formation in the San Juan Basin, New Mexico and Colorado. Palaeontologia Electronica, Vol.12, Issue 1. Williamson, T.E. (2008). Paleocene palynomorph assemblages from the Nacimiento Formation, San Juan Basin, New Mexico, and their biostratigraphic significance. New Mexico Geology, Vol.30, Number 1. Fassett, J.E., Fastovsky, D.E and P.M. Sheehan (2005). Comment and Reply. The extinction of dinosaurs in North America. GSA Today, Vol.15, Number 3. Buck, B.J.,et al. (2004). "Tertiary Dinosaurs" in the Nanxiong Basin, Southern China, Are Reworked from the Cretaceous. The Journal of Geology, Vol.112. Zhao, Z., et al. (2002). A possible causal relationship between extinction of dinosaurs and K/T iridium enrichment in the Nanxiong Basin, South China: evidence from dinosaur eggshells. Palaeogeography, Palaeoclimatology, Palaeoecology, 178. Fassett, J.E., R.A. Zielinski and J.R. Budhan (2002). Dinosaurs that did not die: Evidence for Paleocene dinosaurs in the Ojo Alamo Sandstone, San Juan Basin, New Mexico. Geological Society of America Special Papers, 356. (NOT AVAILABLE for free but reference included for chronology.) Fassett, J.E., et al. (2001). Compelling New Evidence for Paleocene Dinosaurs in the Ojo Alamo Sandstone, San Juan Basin, New Mexico and Colorado, USA. Catastrophic Events Conference. Zhao, Z., et al. (1991). Extinction of the Dinosaurs Across the Cretaceous-Tertiary Boundary in Nanxiong Basin, Guangdong Province. Vertebrata PalAsiatica, 29(1).
  3. Hugolee has a recent post showing pictures of dugong bone. The responses to his post tickled my interest in the subject and caused me to do a little research on both manatees and dugongs. I am now more intelligent regarding this subject, BUT could not figure out a question that came to mind. Any help in educating me is appreciated!! Waters in Florida must have been infested with dugongs for as many bones that are found. Dugongs in Florida died out at the time that manatees arrived. WHY???? Was it possible that manatees outcompeted the dugongs? I saw a cold snap was given as a reason for a particular population studied. Was this the reason for all dugongs? If so, why did the manatees survive the cold? Just askin!!! Mike
  4. Does anyone know when Bison died out in Iowa? I myself have a single vertebrae and the front lower left half of a buffalo jaw with 2 teeth in it. I think it must be any wear from 500-to a couple thousand years as it is dark brown in color. 16 - 1.webp
  5. Diatoms are monocellular organisms which contain chlorophyll, and manufacture their own food in the same manner as plants, through the process of photosynthesis. They are one of the major producers of the Earth's oxygen. Their long geological history makes them very useful in the correlation of sedimentary rocks, and they are of equal value in reconstructing paleoenvironments. They are remarkably common everywhere there is any water at all! I have studied fossil marine diatoms for many years, as they are my primary interest in the microfossil world. Many of them are quite beautiful, and they are a favorite subject with many persons who enjoy photomicrography. My primary interest is in diatom taxonomy and evolution, not photography, so I'm afraid my images don't really do them justice. Centric diatoms exhibit radial symmetry, from circular to triangular, and all points between. Oval shapes are not uncommon. The oldest specimens of essentially modern diatom types are from the Cretaceous, and one of the very best localities is the Moreno Shale, which crops out in the Panoche Hills of California. Many diatomists have worked on this flora, and it is fairly well understood. Here we see two of the common taxa from this source. (The bar across the top of the Azpeitiopsis is a sponge spicule, not part of the diatom!) Diatom frustules are composed of secreted silica -- hence they are brittle, but can be virtually indestructible by chemical or diagenetic change in the right sort of environment. (One exception is a highly alkaline environment, which corrodes and ultimately dissolves biogenetic silica.) Other siliceous microfossils include some types of sponge spicules, silicoflagellates (another blog entry coming up perhaps), radiolarians, and ebrideans. At least one family of the foraminifera uses siliceous cement to form their tests. Diatom floras changed radically across the KT boundary, but they are still abundant in the Paleocene. Arguably the world's most famous locality for fossil diatoms is the region around Oamaru, New Zealand, and all collectors have many specimens from there. The age is Late Eocene - Early Oligocene. Somewhat earlier are the many great localities in Russia. Here is a Paleocene specimen from Simbirsk, Ulyanovskaya, Russia. Note that it deviates from pure centric form in that it is slightly ovoid. My own specialty is the diatoms of the Miocene. The United States is blessed with superb Miocene localities on both coasts, many well-known to members of this forum, because most of them can also produce superb shark teeth. The earliest known Miocene flora in the US comes from sites in Maryland: near Dunkirk, Nottingham, and other lesser known localities along the Patuxent River. All of these sites began to be explored in the mid-19th Century, because the diatoms are so perfectly preserved, to say nothing of abundant! These sites are in the lowest part of the Calvert Formation; indeed, there is an unconformity above them that lasted for a considerable period of time, and the diatom flora exhibits considerable changes across it. This part of the Miocene section belongs to the Burdigalian Stage, and age-equivalent diatoms are found also in bore holes and artesian wells at Atlantic City, New Jersey. An index fossil for the East Coast Burdigalian is the following taxon: This species of Actinoptychus evolved relatively quickly, and became extinct at the end of the Burdigalian. It is remarkably beautiful under the microscope, especially in color images, as fine structures in the silica serve as diffraction gratings. I regret that I have no color image in my photo library: I need to make a few! The Calvert Cliffs are rich in fossil diatoms, also, from the later, Middle Miocene. The above is but one example of the many marvelous specimens that can be found in the Calvert. If you're walking the beach for shark teeth, and have access to a microscope such as that used in microbiology or pathology labs, or even the type used in high school biology labs, grab a sample of the sediment. Soak it in water until it disaggregates into mud, let it settle until the water is just a bit cloudy, and put a drop on a microscope slide with a coverslip. A magnification of 100X should reveal diatom frustules (or fragments thereof) among the remaining, unsettled particles of silt. Diatomists all have their own protocols to get such specimens almost perfectly clean, and permanent slides made with a mountant of high refractive index can be utterly gorgeous. I am currently working most intensely on samples from the somewhat later Choptank Formation, that outcrops at Richmond, Virginia. This is another locality that produces excellent specimens: This is one of the most enduring taxa in the geological record, appearing from the early Paleogene right up until the present day, and it can be very abundant. A common triangular form. There are many genera of triangular centric diatoms. And other radial shapes are possible, too: So far as I am aware, this unique specimen is the earliest known example of this taxon, which is still found today in tropical waters. The breakage in the top "arm" is unfortunate, but what can I say: the specimen is, thus far, unique. One might expect modern contamination of the sample, were it not for the fact that the Richmond localities occur far from the contemporary ocean coast -- they are not "watered" by modern waves! That's it -- the 3.95 MB limit..............................
  6. Back to the Cretaceous badlands. Fall has come to the Alberta Badlands and cooler temperatures. This is a positive for exploring the steeper slopes and KT dino extinction boundary high above the Red Deer River. This report is a bit top heavy in scenery photos. Didn't want to get sidetracked by fossils along long trek through lower levels or would never make it up to the destination. Encountered Bullwinkle a couple of kms before our driving destination. Lots of wildlife this day including grouse, mule deer , coyotes and a million migrating waterfowl. Need to push our way through some non-badland topography. Boreal and aspen forests.
  7. According to this recent study, the popular belief that mammals diversified after the extinction that killed the non-avian dinosaurs is incorrect; mammals diversified in the shadow of the dinos long before the extinction, and actually had a drop in diversity after it. The reason for this diversification was the evolution of angiosperms (flowering plants), which provided mammals with new food sources. Research paper: http://rspb.royalsocietypublishing.org/content/283/1832/20160256 Simplified version: http://www.sci-news.com/paleontology/early-mammals-diversification-03931.html
  8. Interesting paper that suggests ichthyosaurs went extinct because of climate change. http://www.abc.net.au/news/2016-03-09/ichthyosaurs-may-have-been-wiped-out-by-climate-change/7230400 Izak
  9. Could all of the large meteorite impacts, especially the one(s) that drove the dinosaurs to extinction, increase the earths gravity? And if so is it likely this is a big factor in the next evolutionary step for dinosaurs, feathered flight?
  10. Taken from my recent blog post: http://redleafz.blogspot.ca/2013/04/five-islands-provincial-park-2012.html Here's another of my belated posts on one of my trips last year. Me and my buddy Craig went for one of many trips to the beautiful town of Parrsboro, Nova Scotia. From town, we headed East towards the small village of Five Islands, which has a Provincial park of the same name: Five Islands Provincial Park. Islands from right to left: Moose i., Diamond i., Long i., Pinnacle i., Egg i., Pinnacle rock Five Islands Provincial Park is a location that has witnessed several events, including a major extinction. Most of the rocks South of the park, towards Red Head and continuing on to Lower Economy, are of a red sandstone from the Triassic Period. These red sandstones from around Red Head are indicative of an arid, desertic climate. On top of the Triassic rock is a layer that corresponds to the Triassic-Jurassic boundary, sandwiched between Triassic sandstone and Jurassic basalts right on top of it. This Triassic-Jurassic layer is identified by its white sandstone and mudstone. The importance of this layer is that it represents one of the major extinction events that had occurred at the boundary. It is still being studied today. The basalts that top these sandstone layers South of the park and protrude West and created the islands, are of the same found at Blomidon and Cape d'Or. These Jurassic age ancient lava flows and dykes could have been part of an active volcanic network seen all over the Minas Basin. The Old Wife is a result of this contorted, violent past. The islands which dot the landscape are also mostly composed of this Jurassic basalt, and some sections of Jurassic sandstones. "Old Wife", with Moose Island in the background The red cliffs just North of the basalt and separated by faults is of Jurassic age. Dinosaur tracks and other fossils have been found occasionally from either the cliff face, or from loose rocks on the beach. A local by the name of Eldon George had found, among many other wonderful fossils, the smallest dinosaur tracks ever found back in the 1980s at Wasson's Bluff, sandstones of the same age and formation not too far from here. See Jon Tattrie's article. Organic layers within water channel Jurassic McCoy Brook Frm. (left), Jurassic North Mountain Frm. (right) But I digress, as I keep rambling on the technical and less on the practical. We arrived at the park when the tide was going down. We walked down the beach and was met with a thick band of fog that was going out the bay. Lava flows Heading South after searching the beach for agate and fossil fragments, the fog lifted and the Sun came out. We went around the Old Wife and headed towards Red Head. Fault running through columnar basalt Beach made up of basalt and minerals "Red Head", seperating the Triassic-Jurassic Blomidon Frm. (West) and Triassic Wolfville Frm. (East) Triassic Wolfville Frm. red sandstone cliffs Modern day trackways (crab) This area is only accessible at extreme low tide, so the window of opportunity is very small. Getting trapped or stranded is a very highly probable so good planning and looking up the tide charts before heading down this way is an ABSOLUTE MUST! This is one of the places in Nova Scotia that I highly recommend visiting, among other sites of course. =)
  11. Atlantic Canadian mega-volcanoes blamed in mass extinction End Triassic extinction wiped out half the world's species 200 Ma (million years ago) http://www.cbc.ca/news/canada/new-brunswick/story/2013/03/22/science-end-triassic-mass-extinction-volcanoes.html Here's another article related to this subject.. http://www.sciencedaily.com/releases/2013/03/130321141450.htm
  12. So I've been doing a lot of research about specie extinction lately, and the overriding trend seems to be a group overspecializes in something that makes them successful. If you look post-mass extinction animals, they are always basic/primitive organisms. This really gives me doubts about the future of man. It seems we have over-specialized in technology and complex governing systems. Anyone who understands chaos theory knows complex systems ALWAYS fail. Is mankind to suffer the same fate at the dinosaurs? Just something that kind of scared the heck out me. Has our reliance on social order and modern living doomed us to extinction? Not even the Dinosaurs were "too big to fail".