Wednesday, March 30, 2011

The Geological Boundary at the Canada-US Border

Continental-scale detrital zircon provenance signatures in Lower Cretaceous strata, western North America. 2011. A.L. Leier and G.E. Gehrels. Geology, First published online March 8


New research shows that rock formations roughly along the same Canada-US political boundary formed as early as 120 million years ago.
Andrew Leier set out to prove what he thought was the obvious: because the mountains are continuous between the U.S. and Canada, the ancient river systems that flowed from these uplands were likely interconnected. In other words, during Cretaceous Period, 120 million years ago, rivers should have flowed north and south between the countries, paying no mind to the modern day political border.

Zircon found in sandstones helped the researchers locate where the sediments had originally formed. Knowing its current location, Leier was able to determine just how far the rivers moved it and the direction from which it came.

During the Cretaceous Period, mountains were being created all along western North America, in both Canada and the United States.

"I thought the sediment transported by ancient rivers in Montana and Utah would flow out of the mountain ranges and then north into Alberta. This is similar with how the Ganges River runs parallel to the Himalayas. Our research shows this wasn't the case," says Leier.

"Cretaceous sediment in the United States have a clear American signature; whereas those in the Canadian Rockies have a different and definable Canadian signature," says Leier.

"The demarcation is pretty much coincidental with the modern day border."

Also the implication of the data suggests that the rivers that flowed west to east from the mountains in the United States stayed in the United States, and those in Canada stayed in Canada.

"In other words, there is no evidence that rivers in western North America were crossing what is today the border," says Leier. link

Proposed This Day: Geological Classification

In 1759, Italian geologist Giovanni Arduino (1714-1795) dated a letter to Professor A.Vallisneri the younger, in which Arduino proposed a classification of Earth's surface rocks according to four brackets of successively younger orders: Primary, Secondary, Tertiary and Quaternary. These are the four geological eras used today.

Wonder Woman © DC Comics, Feb., 1954
The volcanic rocks without fossils which he saw in the Atesine Alps that formed the cores of large mountains he called Primary. Overlying them, the fossil rich rocks of limestone and clay that were found on the prealpine flanks of the mountains he called Secondary. The less consolidated fossil-bearing rocks of the subalpine foothills, he named Tertiary, and the alluvial rock deposits in the plains were the Quaternary. link.

Sunday, March 27, 2011

CT Scan of Nanotyrannus (CMNH 7541)

The Cleveland tyrannosaur skull (Nanotyrannus or Tyrannosaurus): new findings based on ct scanning, with special reference to the braincase. Lawrence M. Witmer & Ryan C. Ridgely, Kirtlandia 37: 61-81.


Abstract: The Cleveland Museum of Natural History’s skull of a small tyrannosaurid theropod dinosaur (CMNH 7541) collected from the Hell Creek Formation has sparked controversy, with competing hypotheses suggesting that it represents a separate taxon of dwarf tyrannosaurid (Nanotyrannus lancensis), a juvenile specimen of Tyrannosaurus rex (the only other acknowledged Hell Creek tyrannosaurid), or a compromise position (a juvenile Nanotyrannus). Beyond this controversy, CMNH 7541 holds importance because of the anatomical information that such a well preserved skull can provide, and it is in this context that we have sought to probe the structure of the braincase region (e.g., pneumatic sinuses, cranial nerve foramina), as well as other regions of the skull.

We subjected the skull to computed x-ray tomography (CT scanning), followed by computer analysis and 3D visualization. The braincase and a number of other bones (e.g., vomer, quadrate, quadratojugal, palatine, mandible) were digitally "extracted" from the CT datasets. Although the new findings strongly confirm the long-held view that CMNH 7541 pertains to a tyrannosaurid, the mosaic of characters it presents makes finer taxonomic assignment difficult. For example, some characters support affinities with T. rex, yet other characters argue for a much more basal position.

The key question that awaits resolution is whether the differences observed can be attributed to juvenility, and such resolution will require information from new, as yet unpublished specimens. Nevertheless, some of the differences seen in CMNH 7541 (e.g., the pattern of pneumatic foramina in the basicranium) are highly divergent and are harder to attribute to ontogeny. Among other findings, we report here thin, laminar structures within the main nasal airway that are interpretable as being respiratory turbinates, which have potential implications for metabolic physiology.
I missed noting that the most recent issue of the CMNH's journal, Kirtlandia, was published last December. The issue is a special tribute to the former CMNH VP curator, Dr. Michael Williams. It includes new, original research on Paleozoic fishes, but also features this long awaited paper by Witmer and Ridgely.

Copies of the full volume can be obtained by contacting our librarian, Wendy Wasman at wwasman at cmnh.org

Visit the CMNH Harold T. Clark Library Blog here.

Born This Day: Richard Denning


Denning (March 27, 1914 – Oct. 11, 1998) had a long career in Hollywood before moving into TV (notably Hawaii Five-O) in the 1960’s.

He had starring roles in a number of Sci-Fi flicks including Unknown Island (1948), Day the World Ended (1955), Creature with the Atom Brain (1955) and Black Scorpion (1957), but he takes a bow here for playing the greedy Dr. Mark Williams in 1954’s, Creature from the Black Lagoon.

Saturday, March 26, 2011

Died This Day: James Hutton

Hutton (June 3, 1726 – March 26, 1797) is the 'Father of Uniformitarianism' which explains the features of the Earth's crust by means of natural processes over geologic time. Link



More Info Here

Happy Birthday To Richard Dawkins

Friday, March 25, 2011

Soft Skin Preservation In 50 Million Year Old Reptile

Infrared mapping resolves soft tissue preservation in 50 million year-old reptile skin. 2011. N. P. Edwards, e tal. Proc. B., published online before print March 23.


© Marvel Comics
Scientists have published the brightly-coloured image shows the presence of amides – the organic compounds, or building blocks of life – in the ancient skin of a reptile, found in the 50 million year-old rocks of the Green River Formation in Utah, USA.


These infra-red maps are backed up by the first ever element-specific maps of organic material in fossil skin generated using X-rays at the Stanford synchrotron in the USA.


When the original compounds in the skin begin to break down they can form chemical bonds with trace metals, and under exceptional conditions these trace metals act like a 'bridge' to minerals in the sediments. This protects the skin material from being washed away or decomposing further.

"The mapped distributions of organic compounds and trace metals in 50 million year old skin look so much like maps we've made of modern lizard skin as a check on our work, it is sometimes hard to tell which is the fossil and which is fresh."


These new results imply that trace metal inventories and patterns in ancient reptile skin, even after fossilisation, can indeed be compared to modern reptiles. link

Thursday, March 24, 2011

Reanalyzing The Original Primordial Soup

Primordial synthesis of amines and amino acids in a 1958 Miller H2S-rich spark discharge experiment. 2011. E.T. Parker, et al. PNAS, Published online before print March 21.


FF © Marvel Comics. Thanks to AS
Stanley Miller gained fame with his 1953 experiment showing the synthesis of organic compounds thought to be important in setting the origin of life in motion. Five years later, he produced samples from a similar experiment, shelved them and, as far as friends and colleagues know, never returned to them in his lifetime.

More 50 years later, Jeffrey Bada, Miller's former student, discovered the samples in Miller's laboratory material and made a discovery that represents a potential breakthrough in the search for the processes that created Earth's first life forms.


Unanalyzed samples from a 1958 Stanley Miller. The vials have been relabeled but the boxes are marked with Miller's original notes. Photo: Scripps Institution of Oceanography.
Miller's 1958 experiment in which hydrogen sulfide was added to a mix of gases believed to be present in the atmosphere of early Earth resulted in the synthesis of sulfur amino acids as well as other amino acids. The analysis by Bada's lab using techniques not available to Miller suggests that a diversity of organic compounds existed on early planet Earth to an extent scientists had not previously realized.

"Much to our surprise the yield of amino acids is a lot richer than any experiment (Miller) had ever conducted," said Bada.

The new findings support the case that volcanoes — a major source of atmospheric hydrogen sulfide today — accompanied by lightning converted simple gases into a wide array of amino acids, which are were in turn available for assembly into early proteins.

Bada also found that the amino acids produced in Miller's experiment with hydrogen sulfide are similar to those found in meteorites. This supports a widely-held hypothesis that processes such as the ones in the laboratory experiments provide a model of how organic material needed for the origin of life are likely widespread in the universe and thus may provide the extraterrestrial seeds of life elsewhere.

Successful creation of the sulfur-rich amino acids would take place in the labs of several researchers, including Miller himself, but not until the 1970s.

"Unbeknownst to him, he'd already done it in 1958," said Bada. link

A New Early Cambrian Hemichordate


Image: D. Siveter, Oxford Univ.
A new 525-million-year-old pterobranch hemichordate fossil belongs to a group of tentacle-bearing creatures which lived inside hard tubes. Previously only the tubes have been seen in detail but this new specimen clearly shows the soft parts of the body including tentacles for feeding.

Galeaplumosus abilus means 'feathered helmet from beyond the clouds', referring to both the creature's shape and its location – 'Yunnan' literally translates as 'south of the clouds'.

Pterobranch hemichordates which are related to starfish and sea urchins but also show some characteristics that offer clues to the evolution of the earliest vertebrates. About 30 species of pterobranch are known to exist today although 380-490 million years ago a group of these animals called graptolites were common across the prehistoric oceans.

Pterobranches are creatures which secrete a substance that builds up into a hard tube around their soft body. Tentacles extend from the top of the tube to catch plankton. Although less than 4cm in length, the new fossil is beautifully preserved and minute details can be seen including 36 tiny tentacles along one feathery arm. link

Happy Birthday to Bob Bakker


image

Read more about him HERE

Wednesday, March 23, 2011

Born This Day: Kenneth Tobey

Tobey (Mar. 23, 1917 - Dec. 22, 2002) made a career of playing “take charge, men of authority”, such as Capt. Hendry in Howard Hawkes, “The Thing From Another World” (1951), and just about every TV series throughout the 60’s and 70’s. More than a few of his appearances were in SF stories, and he played Col. Jack Evans in The Beast from 20,000 Fathoms (1953).

Tuesday, March 22, 2011

Born This Day: Adam Sedgwich

From Today In Science History:

Adam Sedgwich (March 22, 1785 - January 27, 1873) was an English geologist who first applied the name Cambrian to the geologic period of time, now dated at 570 to 505 million years ago. In 1818 he became Woodwardian Professor of Geology at Cambridge, holding a chair that had been endowed ninety years before by the natural historian John Woodward.

He lacked formal training in geology, but he quickly became an active researcher in geology and paleontology. Many years after Sedgwick's death, the geological museum at Cambridge was renamed the Sedgwick Museum of Geology in his honor. The museum is now part of the Department of Earth Sciences at Cambridge University

Friday, March 11, 2011

Died This Day: Roy Chapman Andrews

(Jan.26, 1884-Mar.11, 1960)

American naturalist, explorer, and author, who spent his entire career at the American Museum of Natural History. He led many important scientific expeditions with financial support through his public lectures and books, particularly in central Asia and eastern Asia. On his 1925 central Asian expedition, the first known dinosaur eggs were discovered,as well as skull and parts of Baluchitherium, the largest known land mammal. During his career Andrews was the museum's best promoter, creating immense excitement and successfully advancing research there. link

Andrews was also acknowledged as one of the more important inspirations for the creation of the character of Indiana Jones.

Wednesday, March 09, 2011

Died This Day: Mary Anning

Mary Anning (May, 21 1799 - March 9, 1847) was an English fossil collector who made her first significant discovery at the age of 11 or 12 (sources differ on the details), when she found a complete skeleton of an Ichthyosaurus, from the Jurassic period . The ten-meter (30 feet) long skeleton created a sensation and made her famous. Anning's determination and keen scientific interest in fossils derived from her father's interest in fossil hunting, and a need for the income derived from them to support her family after his death in 1810.

She sold large fossils to noted paleontologists of the day, and smaller ones to the tourist trade. In 1823, Anning made another great discovery, found the first complete Plesiosaurus. Later in her life, the Geological Society of London granted Anning an honorary membership.

From From Today in Science History.

Monday, March 07, 2011

Evolution Made Us All

Evolution Made Us All from Ben Hillman on Vimeo.

How Big Was A Pterosaur's Wing Membrane?

The extent of the pterosaur flight membrane. Elgin, R. A., et al. Acta PalaeontologicaPolonica 56: 99–111.



Abstract: The shape and extent of the membranous brachioptagium in pterosaurs remains a controversial topic for those attempting to determine the aerodynamic performance of the first vertebrate fliers. Various arguments in favour of the trailing edge terminating against either the torso or hip, the femur, the ankle, or different locations for various taxa, has resulted in several published reconstructions. Uncertainty over the correct model is detrimental to both aerodynamic and palaeoecological studies that are forced to simultaneously consider multiple and highly variable configurations for individual taxa.



A review of relevant pterosaur specimens with preserved soft tissues or impressions of the wing membrane, however, strongly suggests that the trailing edge of the wing extended down to the lower leg or ankle in all specimens where the brachiopatagium is completely preserved. This configuration is seen across a phylogenetically broad range of pterosaurs and is thus likely to have been universally present throughout the Pterosauria.

Support for opposing hypotheses where the trailing edge terminates against the body, hip, or knee are based on several specimens where the wing membrane is either incomplete or has undergone post−mortem contraction. An ankle attachment does not rule out a high aspect ratio wing as the curvature of the trailing edge and the ratio of the fore to hind limbs also play a major role in determining the final shape of the membrane.

Died This Day: St. Thomas Aquinas

Thomas (born c. 1225 - March 7, 1274) Italian theologian who wrote commentaries on Aristotle. Following Aristotle's definition of science as sure and evident knowledge obtained from demonstrations, Thomas defined science as the knowledge of things from their causes. In his major work, Summa, he distinguished between demonstrated truth (science) and revealed truth (faith).

In some natural science he was insightful, such as: "In the same plant there is the two-fold virtue, active and passive, though sometimes the active is found in one and the passive in another, so that one plant is said to be masculine and the other feminine." In Summa , however, he made the erroneous observation that metals are formed by rays from the Sun, Moon, and planets, each governing a particular metal. From Today In Science History.

Born This Day (1930): Stanley Lloyd Miller

From Today in Science History:


Miller is an American chemist who made a series of famous experiments beginning in 1953, to determine the possible origin of life from inorganic chemicals on the primeval earth.

He passed electrical discharges (simulating thunderstorms) through mixtures of reducing gases, such as hydrogen, ammonia, methane and water, that were believed to have formed the earliest atmosphere.

An analysis days later showed that the resulting chemicals included glycine and alanine, the simplest amino acids & the basic building blocks of proteins. Other compounds included urea, aldehydes and carboxylic acids. Thus, a "primeval soup" is the currently accepted most plausible explanation, though incomplete, of the origin of the complex organic molecules of life.

Sunday, March 06, 2011

The Shape of Things To Come by Geof Darrow


© Geof Darrow

From an old issue of Cheval Noir. Click to enlarge

More Fossils In Meteorites

Fossils of Cyanobacteria in CI1 Carbonaceous Meteorites. 2011. Richard B. Hoover. Journal of Cosmology 13


A NASA scientist has discovered evidence of microfossils similar to Cyanobacteria, in freshly fractured slices of the interior surfaces of the Alais, Ivuna, and Orgueil CI1 carbonaceous meteorites.

Based on Field Emission Scanning Electron Microscopy (FESEM) and other measures, Dr. Hoover has concluded they are indigenous to these meteors and are similar to trichomic cyanobacteria and other trichomic prokaryotes such as filamentous sulfur bacteria.

He concludes these fossilized bacteria are not Earthly contaminants but are the fossilized remains of living organisms which lived in the parent bodies of these meteors, e.g. comets, moons, and other astral bodies. The implications are that life is everywhere, and that life on Earth may have come from other planets. link

It's hard to say if this on-line journal can be taken seriously given its cheesy web site covered with ads. Even the link in the title of this paper (not the link I've given you) takes you to Amazon.com!

Thursday, March 03, 2011

Died This Day: Sewell Wright

From the ever eloquent Today In Science History:

Wright (Dec. 21, 1889 – March 3, 1988) was an American geneticist who was one of the founders of modern theoretical population genetics. He researched the effects of inbreeding and crossbreeding with guinea pigs, and later on the effects of gene action on inherited characteristics. He adopted statistical techniques to develop evolutionary theory.

Wright is best known for his concept of genetic drift, called the Sewell Wright effect - that when small populations of a species are isolated, out of pure chance the few individuals who carry certain relatively rare genes may fail to transmit them. The genes may therefore disappear and their loss may lead to the emergence of new species, although natural selection has played no part in the process.

Check out genetic drift at The Biology Project at The University of Arizona.

Learn more about Wright HERE. Image from HERE

Wednesday, March 02, 2011

Premiered This Day: King Kong



The movie King Kong was one of the most successful films released in 1933. It went on to inspire many young fans (both in its initial release, numerous re-releases, and on television) to take up the professions of either film-making or paleontology. The field of dinosaur paleobiology would be very different today if King Kong had never met Fay Wray on Skull Island "way west of Sumatra" and been taken to the concrete jungle of New York.

In a remarkable coincidence the artist, Willis O'Brien, who created and brought Kong to life, celebrated his 47th birthday on the day the movie debuted in New York City.

Born This Day: Willis O'Brien

A tip of the fedora to the late, great Willis O'Brien who breathed life into the fur and armature that become King Kong, the 8th Wonder of the World!


His biography from Leonard Maltin's Movie Encyclopedia:

Willis O'Brien (March 2, 1886 - November 8, 1962)
Special effects wizard best known to the world as the man who
created King Kong.
O'Brien was a sculptor and cartoonist for the San Francisco "Daily News" before he first dabbled in the medium of film during the 'teens. His work caught the attention of the Edison company, for whom he produced several short subjects with a prehistoric them. Titles include The Dinosaur and the Missing Link, RFD 10,000 B.C and Prehistoric Poultry. His method of animating small rubber figures, carefully molded over metal skeletons with movable joints, by moving them a fraction of an inch for each frame of film exposed, became the standard process of live-action animation.

In 1918 he made his most ambitious film yet, The Ghost of Slumber Mountain paving the way for The Lost World (1925), a major Hollywood feature which told of a search for prehistoric creatures. O'Brien's dinosaurs were his most realistic yet, and still impress today, even in the wake of Jurassic Park Still, Obie (as he was known) kept experimenting.


When producer Merian C. Cooper saw his work, he hired O'Brien to animate King Kong (which, up to that point, was to have been shot with an actor in a gorilla suit). The extraordinary success of King Kong (1933) spawned an immediate sequel, The Son of Kong (also 1933), and made O'Brien a hero to several generations of fantasy filmmakers to come. O'Brien won his only Oscar for his effects in Mighty Joe Young (1949), another giant-monkey movie, on which his protégé (and successor) Ray Harryhausen worked.

O'Brien worked on other giant-monster movies (including 1957's The Black Scorpion his last) before dying in 1962. Today, O'Brien would be kingpin of his own studio, but even in the wake of King Kong he had trouble launching other film projects, and many promising ideas languished on studio drawing boards for decades to follow. One of the RKO staff with whom he'd worked in the 1930s, Linwood Dunn, gave O'Brien his final employment, doing stop-motion figures for It's a Mad Mad Mad Mad World (1963).


In 1950 O'Brien received (finally!) a special Oscar for his work on Mighty Joe Young which was the first such award ever given for special effects. This film also launched the career of the next great stop-motion animator, Ray Harryhausen.