Monday, April 27, 2009

Opened This Day: AMNH

From Today In Scince History:

On this day in 1871, the American Museum of Natural History opened to the public in New York City. The Museum’s collection went on view for the first time in the Central Park Arsenal, the Museum’s original home, on the eastern side of Central Park.

The museum began from the efforts of Albert Smith Bickmore, one-time student of Harvard zoologist Louis Agassiz, who was successful in his proposal to create a natural history museum in New York City, with the support of Theodore Roosevelt and J. Pierpont Morgan. The Governor of New York signed a bill officially creating the American Museum of Natural History on April 6, 1869.

Sunday, April 26, 2009

Premiered This Day: The Creature Walks Among Us


Back on this day in 1956 the second sequel to The Creature From the Black Lagoon debuted. It's long been considered the weakest film in the trilogy, and it's hard to argue this given that they drag The Creature out of the Amazon, burn him in a fire, and convert him into an air-breathing humanoid with no hope of ever returning to the waters. But, when viewed today, the film takes on deeper meanings than I'm sure were originally intended.

The plot and language of the film can now be taken to speak directly to the hot-button topics of genetic manipulation of animals and foods, and man's destructive meddling with nature leading to accelerated rates of extinction. The movie moves beyond being a simple “monster on the rampage” story and actually has some pointed comments to make about science and politics. It's well worth watching on one of those upcoming hot, humid summer nights.

Kirby & Ditko's Goliath


Jack Kirby and Steve Ditko team up on an early '60's monster story, complete with a dinosaur cameo so's that I can plug it here.

Goseong Dino Expo, Part 2

More photos from the giant dino expo in Korea. In addition to dozens of life-sized and over-sized dino models there were a series of themed pravillions featuring both original and cast fossils. The Velociraptor, Tarbosaurus, and Prorceratops from the Cretaceous pravillion are real; most of the saurpod mounts in the Juarssic pravillion are casts.























Thursday, April 23, 2009

Puijila darwini: Fossil Seal With Legs

A semi-aquatic Arctic mammalian carnivore from the Miocene epoch and origin of Pinnipedia. 2009. N. Rybczynski, et al., Nature 458: 1021-1024.


The 24 to 20 million-year-old fossil skeleton of Puijila darwini was found in the summer of 2007 during a fieldwork expedition on Devon Island, Nunavut, in a meteor impact crater. It resembled an otter, but a skull that is more closely related to seals. A "walking seal", Puijila had legs like a terrestrial mammal, but the feet were webbed and adapted for swimming. This surprisingly complete skeleton (about 65%) is the most primitive pinniped skeleton found so far.


"Puijila is the first fossil evidence that early pinnipeds lived in the Arctic," explains Rybczynski. "This discovery supports the hypothesis that the Arctic may have been a geographic centre in pinniped evolution."

Puijila darwin will be on display at the Canadian Museum of Nature in Ottawa from April 28 to May 10, 2009. A model of the skeleton will be included in Extreme Mammals, an exhibition opening May 16, 2009 at the American Natural History Museum in New York, co-sponsered by the Cleveland Museum of Natural History. link

Puijila even has its own web site.

Tuesday, April 21, 2009

Goseong Dinosaur Expo, Korea

Goseong province on the south coast hosts a giant dinosaur expo every three years. During this time an immense park is turned into a dinosaur event that covers several square kilometers and features multiple themed pavilions (Cretaceous, Jurassic, etc.), tons of dino sculptures and a dino museum that would put most museums in NA to shame. Here are some more photos:



Brent Breithaupt walks the shoreline path to the main expo site.

Yoshi, Junchang, Yuong Nam, Mr. Lee, oops-forgotten her name, Martin Kundrat





The entrance to the temporary Dino Museum


Dave Eberth & sauropod

Expo mascots

One very big therizinosaur!

Monday, April 20, 2009

Getting a Leg Up On the Tetrapod Land-Water Transition

Contrasting Developmental Trajectories in the Earliest Known Tetrapod Forelimbs. 2009. V. Callier et al. Science 324: 364 – 367.


Click HERE for an animation of the humerus from MGUH 29017a. The bone rotates 360° around its long axis, which is oriented vertically.

Ichthyostega and Acanthostega, lived an estimated 360-370 million years ago in what is now Greenland. Acanthostega was thought to have been the most primitive tetrapod, that is, the first vertebrate animal to possess limbs with digits rather than fish fins.

New evidence indicates that Ichthyostega may have been closer to the first tetrapod. In fact, Acanthostega may have had a terrestrial ancestor and then returned full time to the water.

The researchers studied the fossilized bones inside the rock with computed tomography (CT) scanning rather than trying to prepare them out of the matrix. The CT slices revealed that Clack had found the first juvenile forms of Ichthyostega.

The humeri (upper arm bones) suggest that Ichthyostega juveniles were aquatically adapted, and that the terrestrial habit was acquired relatively late in development. The fossils bore evidence that the muscle arrangement in adults was better suited to weight-bearing, terrestrial locomotion than the juvenile morphology. It is possible that Ichthyostega came out of the water only as a fully mature adult.

In contrast, in Acanthostega "there is less change from the juvenile to the adult. Although Acanthostega appears to be aquatically adapted throughout the recorded developmental span, its humerus exhibits subtle traits that make it more similar to the later, fully terrestrial tetrapods.

Because the shapes of its adult limbs seemed the most fin-like, scientists had previously concluded that Acanthostega was "more primitive," Callier said. "But now, if we look at the details of the humeri, Ichthyostega's are actually more similar to earlier fishes."

Ironically, the shape of Acanthostega's limbs, in both adult and the newly-discovered juvenile forms, is more "paddle-like" than Ichthyostega's, Callier said. "They would have been really good swimmers. So, although Acanthostega had limbs with digits, we don't think it was really terrestrial. We think even the adults were aquatic."

"If Ichthyostega is actually more primitive than Acanthostega, then maybe animals evolved towards a terrestrial existence a lot earlier than originally believed," she said. "Maybe Acanthostega was actually derived from a terrestrial ancestor, and then, went back to an aquatic lifestyle." link

Born This Day: Willi Henning

April 20, 1913 – Nov. 5, 1976

From the Willi Hennig Society :

Hennig is best known for developing phylogenetic systematics, a coherent theory of the investigation and presentation of the relations that exist among species. Contrary to the position generally held during his time, Hennig viewed historical inference as a strictly logical and scientific endeavor. He first summarized his ideas in 1950 in German which became more widely known with the publication of the English revision, Phylogenetic Systematics (Hennig, 1966).


image.

Major Hennigian principles are:
1. Relationships among species are to be interpreted strictly genealogically, as sister-lineages, as clade relations. Empirically, a phylogenetic hypothesis may be determined.

2. Synapomorphies provide the only evidence for identifying relative recency of common ancestry. Synapomorphies are understood to be the shared-derived (evolved, modified) features of organisms.

3. Maximum conformity to evidence is sought (his auxiliary principle). Choice among competing cladistic propositions (cladograms) is decided on the basis of the greatest amount of evidence, the largest number of synapomorphies explainable as homologues.

4. Whenever possible, taxonomy must be logically consistent with the inferred pattern of historical relationships. The rule of monophyly is to be followed, thereby each clade can have its unique place in the hierarchy of taxonomic names.
More info about Henning HERE. photo.

Born This Day: Sir William Logan

April 20, 1798 – June 22, 1875

From Today in Science History:

Logan was a Canadian geologist dubbed the "Father of Canadian Geology." He began is career making geologic maps of coalfields in Wales, noting the relationship between the underlying clay layers and fossil tree roots with local coal beds. This substantiated the theory that coal beds are formed in place.

When he began as director (1842-69) of the new Geological Survey of Canada, its geology was virtually unknown. He produced the monumental Report on the Geology of Canada (1863) which recorded 20 years of research, fieldwork, plotting maps, preparing reports, and examining fossil and mineral specimens.

Image and more info from Natural Resources Canada. For a more colourful summary of the man and his life go HERE.

Sunday, April 19, 2009

Died This Day: Charles Darwin

Feb. 12, 1809 – April 19, 1882


stamp

More about Darwin HERE.

Died This Day: Louis Dollo

Dec. 7, 1857 – April 19, 1931

From Today In Science History:

Louis Antoine Marie Joseph Dollo was a French vertebrate paleontologist who stated Dollo's Law of Irreversibility whereby in evolution an organism never returns exactly to its former state such that complex structures, once lost, are not regained in their original form. (While generally true, some exceptions are known.)

He began as an assistant (1882), became keeper of mammals (1891) at the Royal Museum of Natural History in Brussels where he stayed most of his life. He was a specialist in fossil fishes, reptiles, birds, and their palaeoecology.

He supervised the excavation of the famous, multiple Iguanodons found in 1878 by miners deep underground, at Bernissart, Belgium. image

Saturday, April 18, 2009

Goseong Dinosaur Symposium & Expo in Korea

Last week I was at the Goseong International Dinosaur Symposium and Expo in Korea. Our host, Dr. Yuong Nam Lee, and the mayor of Geosong put on a great event and treated us very well. After a day and a half of talks we toured the Goesong Dinosaur Museum, the Dinosaur Expo site, and some of the many trackway and footprint sites in Korea.

I'll be posting photos from this trip over the next few days, starting with a with some from one of the track sites on the south coast:




Yuong Nam Lee explains it all.








Friday, April 17, 2009

Origin of the Earliest Vascular Land Plants

Origin and Radiation of the Earliest Vascular Land Plants. 2009. P. Steemans, et al. Science 324: 353.


Sporr © Marvel Comics
Abstract: Colonization of the land by plants most likely occurred in a stepwise fashion starting in the Mid-Ordovician. The earliest flora of bryophyte-like plants appears to have been cosmopolitan and dominated the planet, relatively unchanged, for some 30 million years. It is represented by fossilized dispersed cryptospores and fragmentary plant remains.

In the Early Silurian, cryptospore abundance and diversity diminished abruptly as trilete spores appeared, became abundant, and underwent rapid diversification. This change coincides approximately with the appearance of vascular plant megafossils and probably represents the origin and adaptive radiation of vascular plants.

We have obtained a diverse trilete spore occurrence from the Late Ordovician that suggests that vascular plants originated and diversified earlier than previously hypothesized, in Gondwana, before migrating elsewhere and secondarily diversifying.

Wednesday, April 15, 2009

Dino Exploration in the Bonnet Plume Fm, Yukon

Last summer, Dr. David Evans from the ROM/U of Toronto, took a crew to the Yukon to investigate reports of dinosaur bones from the Bonnet Plume Formation. Recently a reporter from the Yukon News wrote up an “error-riddled article” about the trip that you can read HERE.



Evans got to the spot (above) where the three duck-billed dino bones that were found in the 1960s were recovered, but did not get any more vertebrates. They found some good plant fossils though (below).




All photos © David Evans
The crew from left to right was Matt Vavrek (McGill), Dave Evans, Grant Zazula (Yukon Gov), and Nic Campione (U Toronto).

Dr. Evans will be back up north this June to do some more exploring – good luck!

Hermit Arthropods 500 Million Years Ago?

Hermit arthropods 500 million years ago?. 2009. J. W. Hagadorn and A. Seilacher. Geology 37: 295-298

Abstract: Cambrian intertidal sandstones of North America record early excursions of large animals onto tidal flats, where continuous microbial films served as preservational agents for surface tracks. Whereas biomineralized fossils are rare in such lithofacies, trace fossils from the Late Cambrian Elk Mound Group of Wisconsin illustrate how some arthropods might have managed to withstand the vicissitudes of subaerial exposure—by using foreign shells like hermit crabs.

This behavior is suggested by trackways (Protichnites eremita isp. nov.), which have "tail" impressions that are obliquely segmented and always shingled to the left side. These anomalous impressions are best explained by a dextrally coiled shell intermittently touching the sediment.

However, unlike in modern hermit crabs, this shell was too small to house the whole animal. It probably served only to provide a humid chamber that reduced desiccation of the animal's abdominal gills. The dorsal flexure of the tail, in connection with dextral shell coiling, resulted in left-hand shingling of the touch marks

Study Confirms 3 Neanderthal Sub-Groups

Genetic Evidence of Geographical Groups among Neanderthals. 2009. Fabre V., et al. PLoS ONE 4(4): e5151.


Devil Dinosaur © Marvel Comics
The Neanderthals inhabited a vast geographical area extending from Europe to western Asia and the Middle East 30,000 to 100,000 years ago. Paleoanthropological studies based on morphological skeletal evidence have offered some support for the existence of three different sub-groups: one in Western Europe, one in southern Europe and another in the Levant.

Researchers have given further consideration to the question of diversity of Neanderthals by studying the genetic structure of the mitochondrial DNA (mtDNA) and by analyzing the genetic variability, modeling different scenarios. The study was possible thanks to the publication, since 1997, of 15 mitochondrial DNA (mtDNA) sequences (the mtDNa is maternally transmitted) that originated from 12 Neanderthals.

The new study confirms the presence of three separate sub-groups and suggests the existence of a fourth group in western Asia. According to the authors, the size of the Neanderthal population was not constant over time and a certain amount of migration occurred among the sub-groups. The variability among the Neanderthal population is interpreted to be an indirect consequence of the particular climatic conditions on their territorial extension during the entire middle Pleistocene time period. link

Tuesday, April 07, 2009

Born This Day: Kenneth (Page) Oakley

April 7, 1911 - November 2, 1981

From Today in Science History:

Oakley was an English physical anthropologist, geologist, and paleontologist best known for his work in the relative dating of fossils by fluorine content. While working for the British Natural History Museum, Oakley become famous in 1953 for exposing the 'Piltdown Man' forgery.

"A skull had been "unearthed" in 1912, in Piltdown, England, and had for decades been said to represent the "missing link" in human evolution. Oakley developed a method, based on a French minerologist's theory that bones would gradually absorb fluorine from surrounding soil, to measure the fluorine levels in bones. With this and other tests he proved the bones to be a modern human braincase and an orangutan jawbone chemically stained to appear ancient. image

Monday, April 06, 2009

Born This Day: James Watson

From Today In Science History:

Watson was born on this day in 1928. An American geneticist and biophysicist, he shared the 1962 Nobel Prize for Physiology or Medicine (with Francis Crick and Maurice Wilkins) for the discovery of "the molecular structure of nucleic acids and its significance for information transfer in living material." Deoxyribonucleic acid (DNA) is the substance contained in cells that controls heredity.

Crick and Watson began their collaboration in 1951, and published their paper on the double helix structure on 2 Apr 1953 in Nature. This accomplishment became a cornerstone of genetics and was widely regarded as one of the most important discoveries of 20th-century biology.
image.

Created This Day: The AMNH

In 1869, the American Museum of Natural History in New York City was officially created with the signing of a bill by the Governor of New York, John Thompson Hoffman.

The museum began from the efforts of Albert Smith Bickmore, one-time student of Harvard zoologist Louis Agassiz, who was successful in his proposal to create a natural history museum in New York City, with the support of William E. Dodge, Jr., Theodore Roosevelt, Sr., Joseph Choate, and J. Pierpont Morgan. It opened to the public 27 Apr 1871.

With a series of exhibits, the Museum’s collection went on view for the first time in the Central Park Arsenal, the Museum’s original home, on the eastern side of Central Park.

Also, on this day in 1930, Hostess Twinkies were invented by bakery executive James Dewar.

From Today in Science History.

Sunday, April 05, 2009

Brain Boy Vs. Tyrannosaurus mentalis!


I've linked to some odds things through this blog, but never something as quite "out there" as this story posted over at Atomic Surgery. Go see for yourself.