Monday, May 31, 2010

Medusaceratops lokii

It's been a busy week for ceratopsids. Here's a nice Luis Rey illustration for a new chasmosaur from the Judith River Formation of Montana.

It's another one from the new book, "New Perspectives on Horned Dinosaurs", from Indiana University Press. press release

Sunday, May 30, 2010

The Hero of 50,000,000 B.C.

© DC Comics
A conceited big-game hunter gets transported to the past where he hunts a Styracosaurus with some aliens, and learns a valuable life lesson. Read it at Atomic Surgery.

How To End An Ice Age

Ventilation of the deep Southern Ocean and deglacial CO2 rise. 2010. L.C. Skinner, et al. Science 328: 1147 - 1151.

Scientists have found the possible source of a huge carbon dioxide 'burp' that happened some 18,000 years ago and which helped to end the last ice age.
The results provide the first concrete evidence that carbon dioxide (CO2) was more efficiently locked away in the deep ocean during the last ice age, turning the deep sea into a more 'stagnant' carbon repository – something scientists have long suspected but lacked data to support.

Working on a marine sediment core recovered from the Southern Ocean floor between Antarctica and South Africa, the international team radiocarbon dated shells left behind by tiny marine creatures called foraminifera.

By measuring how much carbon-14 (14C) was in the bottom-dwelling forams' shells, and comparing this with the amount of 14C in the atmosphere at the time, they were able to work out how long the CO2 had been locked in the ocean.

According to Dr Skinner: "Our results show that during the last ice age, around 20,000 years ago, carbon dioxide dissolved in the deep water circulating around Antarctica was locked away for much longer than today. If enough of the deep ocean behaved in the same way, this could help to explain how ocean mixing processes lock up more carbon dioxide during glacial periods."

Because the ocean is a large, dynamic reservoir of carbon, it has long been suspected that changes in ocean circulation must have played a major role in motivating these large changes in CO2. In addition, the Southern Ocean around Antarctica is expected to have been an important centre of action, because this is where deep water can be lifted up to the sea surface and 'exhale' its CO2 to the atmosphere.

Scientists think more CO2 was locked up in the deep ocean during ice ages, and that pulses or 'burps' of CO2 from the deep Southern Ocean helped trigger a global thaw every 100,000 years or so. The size of these pulses was roughly equivalent to the change in CO2 experienced since the start of the industrial revolution. link

Alanqa saharicafrom, A New Pterosaur From Morocco

A New Pterosaur (Pterodactyloidea: Azhdarchidae) from the Upper Cretaceous of Morocco. Ibrahim, N., et al. PLoS ONE 5(5): e10875.

Scientists have announced the discovery of Alanqa saharicafrom, an early pterosaur that lived 95 million years ago in Morocco.
Unearthed in three separate pieces, the jaw bone has a total length of 344 mm. Each piece is well preserved, uncrushed, and unlike most other pterosaur fossils, retains its original three dimension shape.

"This pterosaur is distinguished from all others by its lance-shaped lower jaw which had no teeth and looked rather like the beak of a heron," says Nizar Ibrahim. "During the excavation, we also discovered a partial neck vertebra that probably belonged to the same animal, inferring a wing span of about six metres."

The scientists have named the new pterosaur Alanqa saharicafrom the Arabic word 'Al Anqa' meaning Phoenix, a mythological flying creature that dies in a fire and is reborn from the ashes of that fire. On the same expedition, and in the same region as where the fossils of Alanqa saharica were uncovered, the scientists also discovered fossils of two other previously identified types of pterosaur. This suggests that several types of pterosaurs lived alongside one another in the same region at the time, each probably specializing in a different ecological niche.

"When this pterosaur was alive, the Sahara desert was a river bed basin lush with tropical plant and animal life," explains Ibrahim. "This means there were lots of opportunities for different pterosaurs to co-exist, and perhaps feeding on quite different kinds of prey." link

Saturday, May 29, 2010

Coahuilaceratops , First Horned Dinosaur From Mexico

A new species of horned dinosaur unearthed in Mexico has larger horns that any other species - up to 4 feet long - and has given scientists fresh insights into the ancient history of western North America.
The 72-million-year-old rhino-sized creature - Coahuilaceratops magnacuerna - was a four- to five-ton plant-eater belonging to a group called horned dinosaurs, or ceratopsids. The name Coahuilaceratops magnacuerna (Koh-WHE-lah-SARA-tops mag-NAH-KWER-na), refers to the Mexican state of Coahuila where it was found, and to the Greek word "ceratops" meaning "horned face." The second part of the name, magnacuerna, is a combination of Latin and Spanish meaning "great horn," in reference to the huge horns above the eyes of this dinosaur.

The study, partially funded by the National Geographic Society, was conducted by Mark Loewen, Scott Sampson, Eric Lund and Mike Getty, paleontologists at the Utah Museum of Natural History. Also involved were Andrew Farke of the Raymond M. Alf Museum in Claremont, Calif.; Martha Aguillón-Martínez, Claudio de Leon and Rubén Rodríguez-de la Rosa from the Museum of the Desert in Saltillo, Mexico; and David Eberth of the Royal Tyrrell Museum of Palaeontology in Alberta, Canada.

The new species is to be announced in the book "New Perspectives on Horned Dinosaurs" to be released next week by Indiana University Press.

Coahuilaceratops comes from a rock unit known as the Cerro del Pueblo Formation, which dates to between 71.5 million and 72.5 million years ago. The skeletons, which de Leon discovered in 2001 near the town of Porvenir de Jalpa, approximately 40 miles west of Saltillo, were excavated in 2003. The fossils then were prepared at the Utah Museum of Natural History, requiring two years of meticulous work by skilled volunteer preparator Jerry Golden.

Loewen explained that Coahuilaceratops represents the first occurrence of an identifiable species of horned dinosaur in southern Mexico. "The horned dinosaurs are an extraordinary example of vertebrate evolution," he said. They evolved and diversified on Laramidia along a thin strip of land that stretched from Alaska to Mexico. "Finding this horned dinosaur so far south in Mexico offers us a different picture of what the ancestors of Triceratops were like."

Born This Day: Louis-Jean-Marie Daubenton

Daubenton (May 29, 1716 – Jan 1, 1800) was a French naturalist who was a prolific pioneer in the fields of comparative anatomy and paleontology. Daubenton completed many zoological descriptions (including 182 species of quadrupeds for the first section of Daubenton (May 29, 1716 – Jan 1, 1800) was a French naturalist who was a prolific pioneer in the fields of comparative anatomy and paleontology. Georges Buffon's work Histoire naturelle, 1794-1804). His dissections contributed to productive studies in the comparative anatomy of recent and fossil animals, plant physiology, and mineralogy.

In 1793, he became the first director of the Museum of Natural History in Paris. From Today in Science History Image

Friday, May 28, 2010

Out of The Woods For 'Ardi'?

A palaeoblog tip of the hat to Howie Post, creator of Anthro (here inked by Wally Wood), who passed away earlier this month.
Ardipithecus ramidus – a purported human ancestor that was dubbed Science magazine's 2009 "Breakthrough of the Year" – is coming under fire from scientists who say there is scant evidence for her discoverers' claims that there were dense woodlands at the African site where the creature lived 4.4 million years ago.

Instead, "there is abundant evidence for open savanna habitats," says University of Utah geochemist Thure Cerling, lead author of a critique published as a "technical comment" in the Friday, May 28 issue of Science.

The criticism – by eight geologists and anthropologists from seven universities – is important because the claim that the 4.4-million-year-old fossil nicknamed Ardi lived in woodlands and forest patches was used as an argument against a longstanding theory of human evolution known as the savanna hypothesis.

That hypothesis holds that an expansion of savannas – grassy plains dotted with trees and shrubs – prompted ape-like ancestors of humans to descend from the trees and start walking upright to find food more efficiently or to reach other trees for shelter or resources.

In December, Science named the research that uncovered Ardipithecus and her environment as the 2009 "Breakthrough of the Year," citing how the fossils were more than a million years older than those of the previously oldest known hominid partial skeleton – that of Lucy, or Australopithecus afarensis.

But a month earlier, in November, Cerling and the seven other scientists submitted their critique to Science. The journal didn't publish it until now – when Cerling and his University of Utah coauthor, geologist Frank Brown, are in the field in Kenya and difficult to reach. Both expressed frustration it took so long.

The critique concludes that Ardi most likely lived in tree or bush savanna with 5 percent to 25 percent of the area covered by trees or shrubs, not the minimum 60 percent to meet the definition of a closed-canopy woodland. Cerling acknowledges Ardi could have lived in a wooded river corridor, but it was a river that flowed through savanna. link

Follow the debate here:

Comment on the Paleobiology and Classification of Ardipithecus ramidus

Response to Comment on the Paleobiology and Classification of Ardipithecus ramidus

Comment on the Paleoenvironment of Ardipithecus ramidus

Response to Comment on the Paleoenvironment of Ardipithecus ramidus

Ajkaceratops kozmai, New Neoceratopsian from Europe

A Late Cretaceous ceratopsian dinosaur from Europe with Asian affinities. 2010. A. Ősi, et al. Nature 465: 466-468.

Abstract: Ceratopsians (horned dinosaurs) represent a highly diverse and abundant radiation of non-avian dinosaurs known primarily from the Cretaceous period (65–145 million years ago). This radiation has been considered to be geographically limited to Asia and western North America, with only controversial remains reported from other continents. Here we describe new ceratopsian cranial material from the Late Cretaceous of Iharkút, Hungary, from a coronosaurian ceratopsian, Ajkaceratops kozmai. Ajkaceratops is most similar to ‘bagaceratopsids’ such as Bagaceratops and Magnirostris, previously known only from Late Cretaceous east Asia.

The new material unambiguously demonstrates that ceratopsians occupied Late Cretaceous Europe and, when considered with the recent discovery of possible leptoceratopsid teeth from Sweden, indicates that the clade may have reached Europe on at least two independent occasions. European Late Cretaceous dinosaur faunas have been characterized as consisting of a mix of endemic ‘relictual’ taxa and ‘Gondwanan’ taxa, with typical Asian and North American groups largely absent. Ajkaceratops demonstrates that this prevailing biogeographical hypothesis is overly simplified and requires reassessment. Iharkút was part of the western Tethyan archipelago, a tectonically complex series of island chains between Africa and Europe, and the occurrence of a coronosaurian ceratopsian in this locality may represent an early Late Cretaceous ‘island-hopping’ dispersal across the Tethys Ocean.

Sinoceratops zhuchengensis, First Ceratopsid from China

First ceratopsid dinosaur from China and its biogeographical Implications. 2010. Xu Xing, et al. Geology 55: 1631-1635

Abstract: Ceratopsid dinosaurs represent one of the best known dinosaur groups in the Late Cretaceous, and their unquestionable fossil records are exclusively restricted to western North America. Here we report a new ceratopsid dinosaur, Sinoceratops zhuchengensis gen. et sp. nov., from the Upper Cretaceous Wangshi Group of Zhucheng, Shandong Province, China. Cladistic analysis places this new taxon as the only known ceratopsid from outside North America, in a basal position within the Centrosaurinae. It is considerably larger than most other centrosaurines but similar in size to basal chasmosaurines. Furthermore, it is more similar to chasmosaurines than to other centrosaurines in several features, thus blurring the distinction of the two ceratopsid subgroups. This new find not only provides significant information on the morphological transition from non-ceratopsid to ceratopsid dinosaurs, but also complicates the biogeography of the Ceratopsidae, and further demonstrates that fossil sampling has profound effects on reconstructing dinosaurian biogeography.

Born This Day: Louis Agassiz

May 28, 1807 - Dec. 14, 1873

(Jean) Louis (Rodolphe) Agassiz was a Swiss-born U.S. naturalist, geologist, and teacher who made revolutionary contributions to the study of natural science with landmark work on glacier activity and extinct fishes. Agassiz began his work in Europe, having studied at the University of Munich and then as chair in natural history in Neuchatel in Switzerland. While there he published his landmark multi-volume description and classification of fossil fish.

In 1846 Agassiz came to the U.S. to lecture before Boston's Lowell Institute. Offered a professorship of Zoology and Geology at Harvard in 1848, he decided to stay, becoming a citizen in 1861. His innovative teaching methods altered the character of natural science education in the U.S. Link

More info HERE

Died This Day: Ralph A. Bagnold

From the always excellent Today in Science History:

Bagnold (April 3, 1896 - May 28, 1990) was an English geologist who was a leading authority on the mechanics of sediment transport, especially eolian (wind) transport. While serving as a soldier in Egypt prior to WW II, Bagnold first studied sand dune formation and movement. After retiring from the army (1935), he continued his research and wrote the book "Physics of Blown Sand and Desert Dunes", investigating the physics of particles moving through the atmosphere and deposited by wind.

Art © Darwyn Cooke. Sand Seref & The Spirit © Estate of Will Eisner
He recognized two basic dune types, the crescentic dune, which he called "barchan," and the linear dune, which he called longitudinal or "sief" (Arabic for "sword"). During WW II, his avocational interest in vehicle performance on blowing sand aided the Allies in North Africa.

Thursday, May 27, 2010

Nectocaris, A Primative Cephalopod from the Burges Shale

Primitive soft-bodied cephalopods from the Cambrian. 2010. M. R. Smith and J.-B. Caron. Nature 465: 469–472.

Abstract [edit]: We reinterpret the problematic Middle Cambrian animal Nectocaris pteryx as a primitive, non-mineralized cephalopod, based on new material from the Burgess Shale. Together with Nectocaris, the problematic Lower Cambrian taxa Petalilium and (probably) Vetustovermis form a distinctive clade, Nectocarididae, characterized by an open axial cavity with paired gills, wide lateral fins, a single pair of long, prehensile tentacles, a pair of non-faceted eyes on short stalks, and a large, flexible anterior funnel.

This clade extends the cephalopods’ fossil record by over 30 million years, and indicates that primitive cephalopods lacked a mineralized shell, were hyperbenthic, and were presumably carnivorous. The presence of a funnel suggests that jet propulsion evolved in cephalopods before the acquisition of a shell. The explosive diversification of mineralized cephalopods in the Ordovician may have an understated Cambrian ‘fuse’

Arrows indicate the crown groups of 1, molluscs; 2, conchifera; 3, cephalopods. Stars represent the earliest record of mineralization in each lineage.

Jeyawati rugoculus

Image by Lukas Panzarin
Congrats to Andrew MacDonald for describing Jeyawati rugoculus, a 91 million year old basal hadrosauroid from western New Mexico.

The partial skull and other fragments of Jeyawati were discovered by paleontologist Douglas Wolfe, principal investigator of the Zuni Basin Paleontological Project. Subsequent excavation and collection was carried out for 13 years with the aid of James Kirkland, state paleontologist with the Utah Geological Survey, and volunteers from the Southwest Paleontological Society, among others.

The research team published their findings in the May issue of the Journal of Vertebrate Paleontology. link

Born This Day: Sandra Shaw

Although Sandra Shaw (May 27, 1913 – Feb. 16, 2000) had a short film career comprising a few, mostly uncredited film roles in 1933, her most famous appearance is that of the person plucked from her sleep from an unnamed hotel by King Kong, and than casually dropped to her death when he realizes that she is not Ann Darrow (Fay Wray). The year that Kong was released she married Gary Cooper.

Arbogast on Film blog has nice appreciation of Sandra Shaw’s few famous film moments.

Wednesday, May 26, 2010

New Perspectives On Horned Dinosaurs Now Published

Well, I got my copy directly from Indiana University Press, so I'm assuming that it will soon be available from all the usual sources.

FYI, the cover is by the very talented Donna Sloan, who works at the Royal Tyrrell Museum. However, it does not actually actually represent one of the 8 new taxa described in the book; but it is a nice Chasmosaurus!

Measuirng A Dinosaur's Body Temperature

Body temperatures of modern and extinct vertebrates from 13C-18O bond abundances in bioapatite. 2010. R. A. Eagle, et al. PNAS published online before print May 24.

Metal Men © DC Comics
Researchers have described the first method for the direct measurement of the body temperatures of large extinct vertebrates—through the analysis of rare isotopes in the animals' bones, teeth, and eggshells.

The technique the team has developed to measure body temperature in extinct vertebrates looks at the concentrations of two rare isotopes—carbon-13 and oxygen-18. "These heavy isotopes like to bond, or clump together, and this clumping effect is dependent on temperature," says Robert Eagle. "At very hot temperatures, you get a more random distribution of these isotopes, less clumping. At low temperatures, you find more clumping."

In living creatures, this clumping can be seen in the crystalline lattice that makes up bioapatite—the mineral from which bone, tooth enamel, eggshells, and other hard body parts are formed. "When the mineral precipitates out of the blood—when you create bone or tooth enamel—the isotopic composition is frozen in place and can be preserved for millions of years," he adds.

"This is not quite like going back in time and sticking a thermometer up a creature's back end," says John Eiler, "but it's close." link

Sunday, May 23, 2010

Born This Day: Carolus Linnaeus

From the Linnean Society:

Linnaeus (May 23, 1707 – Jan. 10, 1778) was born in Sweden. He headed an expedition to Lapland in 1732, travelling 4,600 miles and crossing the Scandinavian Peninsula by foot to the Arctic Ocean. On the journey he discovered a hundred botanical species. He undertook his medical degree in 1735 in the Netherlands. In 1735, he published Systema Naturae, his classification of plants based on their sexual parts.

His method of binomial nomenclature using genus and species names was further expounded when he published Fundamenta Botanica (1736) and Classes Plantarum (1738). This system used the flower and the number and arrangements of its sexual organs of stamens and pistils to group plants into twenty-four classes which in turn are divided into orders, genera and species.

In his publications, Linnaeus provided a concise, usable survey of all the world's plants and animals as then known, about 7,700 species of plants and 4,400 species of animals. These works helped to establish and standardize the consistent binomial nomenclature for species which he introduced on a world scale for plants in 1753, and for animals in 1758, and which is used today.

His Systema Naturae 10th edition, volume 1(1758), has accordingly been accepted by international agreement as the official starting point for zoological nomenclature. Scientific names published before then have no validity unless adopted by Linnaeus or by later authors. This confers a high scientific importance on the specimens used by Linnaeus for their preparation, many of which are in his personal collections now treasured by the Linnean Society.

He was granted nobility in 1761, becoming Carl von Linné. He continued his work of classification and as a physician, and remained Rector of the University until 1772.

Saturday, May 22, 2010

Born This Day: Sir Arthur Conan Doyle

From HERE:

Sir Arthur Conan Doyle (May 22, 1859 – July 7, 1930) was a British writer and creator of Sherlock Holmes. He was born in Edinburgh. His father and uncle were both book illustrators and his mother encouraged his son to explore the world of books. Doyle studied at Edinburgh University and in 1884 he married Louise Hawkins. Doyle qualified as doctor in 1885 and practiced medicine as an eye specialist in Hampshire until 1891 when he became a full time writer. Doyle's first novel about Sherlock Holmes,’ A Study in Scarlet’, was published in 1887.

During the South African war (1899-1902) Doyle served for a few months as senior physician at a field hospital, and wrote ‘The War in South Africa’, in which he defended England's policy. When his son Kingsley died from wounds incurred in World War I, the author dedicated himself in spiritualistic studies.

Doyle's stories of Professor George Edward Challenger in ‘The Lost World’ (1912). The model for the professor was William Rutherford, Doyle's teacher from Edinburgh. Doyle's practice, and other experiences, expeditions as ship's surgeon to the Arctic and West Coast of Africa, service in the Boer War, defenses of George Edalji and Oscar Slater, two men wrongly imprisoned, provided much material for his writings.

The Lost World:

Born This Day: Oliver Perry Hay

May 22, 1846 – Novemeber 2, 1930

Hay was an American paleontologist whose catalogs of fossil vertebrates greatly organized existing knowledge and became standard references. Hay's primary scientific interest was the study of the Pleistocene vertebrata of North America and he is renowned for his work on skull and brain anatomy. His first major work was his Bibliography and Catalogue of the Fossil Vertebrata of North America (1902), supplemented by two more volumes (1929-30). Hay also wrote on the evidence of early humans in North America. link

Friday, May 21, 2010

Born This Day: Mary Anning

May 21, 1799 - March 9, 1847

From Today in Science History:

Mary 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.

Wednesday, May 19, 2010

Premiered This Day (1915): The Dinosaur & The Missing Link

On this day back in 1915, The Dinosaur and The Missing took its bow in US cinemas. It features the earliest work of a young Willis O'Brien who would go on to bring King Kong to life. Watch the film thanks to The Library of Congress.

Part 1:

Part 2:

Humans Came From Where?

Coherent and incoherent inference in phylogeography and human evolution. 2010. A. R. Templeton, PNAS 107: 14 6376-6381.

© Pete Von Sholly. Check out his blog
Templeton has determined that a recently published genetic analysis of deep human DNA evolution is mathematically erroneous and formally illogical. The flaws of the analysis are due to the incorrect application of a statistical method known as approximate Bayesian computation (ABC), which led the authors to support the validity of the controversial “Out of Africa” replacement hypothesis in a 2007 paper. Templeton has previously done a 2005 analysis that disputes this model, showing instead a trellis relationship between different human populations, supporting gene “admixture,” or intermingling.

Templeton got the notion to re-address the Fegundes paper when he noticed claims in a student’s paper using Bayes factors that were just too good to be true. Researching Bayes factors in the primary statistics literature, he found a 1999 paper that the probabilities generated by Bayes factors can be incoherent (result in conclusions that violate logic). He then re-read the Fegundes paper.

“When I first read the paper, I thought something was wrong with it, but I’ve got to admit I didn’t see the incoherence,” Templeton says. “I just saw these probabilities, and they didn’t make any sense to me, but I couldn’t quite pin it down. As soon as I read the 1999 paper, I went back to the 2007 one, and I saw that it was massively incoherent. It arrives at probabilities for different models of human evolution that violate the constraints of formal logic.” link

Born This Day: Carl Akeley

Read his story over at Atomic Surgery

The Hall of African Mammals at the American Museum of Natural History exists thanks to the efforts of Carl Akeley (May 19, 1864 - Nov 17, 1926) who was the kind of adventurer that Indy Jones could only dream of being.

He died on an African expedition in 1926, ten years before this hall was completed and was buried in a place depicted in the Hall's famous Gorilla Diorama. Of course we approach collecting and conservation differently today, but Akeley is to be commended for his love of nature and his desire to present its hidden corners to the world.

From Today In Science History:

Carl Ethan Akeley was an American naturalist and explorer who developed the taxidermic method for mounting museum displays to show animals in their natural surroundings. His method of applying skin on a finely molded replica of the body of the animal gave results of unprecedented realism and elevated taxidermy from a craft to an art. He mounted the skeleton of the famous African elephant Jumbo. He invented the Akeley cement gun to use while mounting animals, and the Akeley camera which was used to capture the first movies of gorillas.

Tuesday, May 18, 2010

Megalodon Nursery Discovered In Panama

Ancient Nursery Area for the Extinct Giant Shark Megalodon from the Miocene of Panama. 2010. C. Pimiento, et al. PLoS ONE: 5 (5).

The six-foot-long babies of the world's biggest shark species, Carcharocles megalodon, frolicked in the warm shallow waters of an ancient shark nursery in what is now Panama.
"Adult giant sharks, at 60-70 feet in length, faced few predators, but young sharks faced predation from larger sharks," said Catalina Pimiento. "As in several modern shark species, juvenile giant sharks probably spent this vulnerable stage of their lives in shallow water where food was plentiful and large predators had difficulty maneuvering."

Paleontologists collected more than 400 fossil shark teeth from Panama´s 10-million-year-old Gatun Formation as part of ongoing work to reveal the origins of this narrow land-bridge that arose to connect North and South America about 3 million years ago. "The 28 teeth that we identified as C. megalodon were mostly from neonates and juveniles," said Pimiento. link

Monday, May 17, 2010

Scopes Monkey Trial Law Repealed

From Today In Science History:

On this day in 1967, the governor of Tennessee signed into law the repeal of the 1925 state law prohibiting the teaching of evolution.

The original law had made it "unlawful for any teacher in any of the Universities, Normals and all other public schools of the State which are supported in whole or in part by the public school funds of the State, to teach any theory that denies the story of the Divine Creation of man as taught in the Bible, and to teach instead that man has descended from a lower order of animals."

It was this law that was tested in what became known as the "Scopes monkey trial." Scopes was found guilty, but acquitted on a technicality upon appeal. The law itself remained a Tennessee state statute for 42 years.

Saturday, May 15, 2010

Archaeopteryx Couldn’t Fly?

Narrow Primary Feather Rachises in Confuciusornis and Archaeopteryx Suggest Poor Flight Ability. 2010. R. L. Nudds and Gareth J. Dyke. Science 328: 887 – 889.

Abstract: The fossil birds Archaeopteryx and Confuciusornis had feathered wings resembling those of living birds, but their flight capabilities remain uncertain. Analysis of the rachises of their primary feathers shows that the rachises were much thinner and weaker than those of modern birds, and thus the birds were not capable of flight.

Only if the primary feather rachises were solid in cross-section (the strongest structural configuration), and not hollow as in living birds, would flight have been possible. Hence, if Archaeopteryx and Confuciusornis were flapping flyers, they must have had a feather structure that was fundamentally different from that of living birds.

Alternatively, if they were only gliders, then the flapping wing stroke must have appeared after the divergence of Confuciusornis, likely within the enantiornithine or ornithurine radiations.

Read the press release

Thursday, May 13, 2010

Died This Day: Georges Cuvier

August 23, 1769 – May 13, 1832
Cuvier's scientific achievements are difficult to overestimate. It was widely recounted that he could reconstruct a skeleton based on a single bone. His work is considered the foundation of vertebrate palaeontology.” link

Read about him at the University of California Museum of Paleontology.

Survival of The Burgess Shale Fauna

Ordovician faunas of Burgess Shale type. 2010. P. Van Roy, et al. Nature 465: 215-218.

Abstract: The renowned soft-bodied faunas of the Cambrian period, which include the Burgess Shale, disappear from the fossil record in the late Middle Cambrian, after which the Palaeozoic fauna dominates. The disappearance of faunas of Burgess Shale type curtails the stratigraphic record of a number of iconic Cambrian taxa. One possible explanation for this loss is a major extinction, but more probably it reflects the absence of preservation of similar soft-bodied faunas in later periods.

Here we report the discovery of numerous diverse soft-bodied assemblages in the Lower and Upper Fezouata Formations (Lower Ordovician) of Morocco, which include a range of remarkable stem-group morphologies normally considered characteristic of the Cambrian.

It is clear that biotas of Burgess Shale type persisted after the Cambrian and are preserved where suitable facies occur. The Fezouata biota provides a link between the Burgess Shale communities and the early stages of the Great Ordovician Biodiversification Event. link

Premiered This Day: Revenge of The Creature

The second of the three ‘Creature’ films, Revenge of the Creature (1955), was again directed by Jack Arnold, with Lori Nelson taking over the role of the damsel in distress.

Wednesday, May 12, 2010

A Formal Test of Common Ancestry

A formal test of the theory of universal common ancestry. 2010. D. L. Theobald. Nature: 465: 219-222.

A nod of the cap to Frank Frazetta who passed away this week.
More than 150 years ago, Darwin proposed the theory of universal common ancestry (UCA), linking all forms of life by a shared genetic heritage from single-celled microorganisms to humans. Until now, the theory has remained beyond the scope of a formal test. This week the results of the first large scale, quantitative test of the famous theory that underpins modern evolutionary biology were reported. It works!
Recent molecular evidence indicates that primordial life may have undergone rampant horizontal gene transfer, which occurs frequently today when single-celled organisms swap genes using mechanisms other than usual organismal reproduction. In that case, some scientists argue, early evolutionary relationships were web-like, making it possible that life sprang up independently from many ancestors.

According to biochemist Douglas Theobald, it doesn't really matter. "Let's say life originated independently multiple times, which UCA allows is possible," said Theobald. "If so, the theory holds that a bottleneck occurred in evolution, with descendants of only one of the independent origins surviving until the present. Alternatively, separate populations could have merged, by exchanging enough genes over time to become a single species that eventually was ancestral to us all. Either way, all of life would still be genetically related."

Harnessing powerful computational tools and applying Bayesian statistics, Theobald found that the evidence overwhelmingly supports UCA, regardless of horizontal gene transfer or multiple origins of life. Theobald said UCA is millions of times more probable than any theory of multiple independent ancestries.

Theobald is the first to formally test Darwin's theory across all three domains of life. The three domains include diverse life forms such as the Eukarya (organisms, including humans, yeast, and plants, whose cells have a DNA-containing nucleus) as well as Bacteria and Archaea (two distinct groups of unicellular microorganisms whose DNA floats around in the cell instead of in a nucleus). Theobald studied a set of 23 universally conserved, essential proteins found in all known organisms.

Just what did this universal common ancestor look like and where did it live? Theobald's study doesn't answer this question. Nevertheless, he speculated, "to us, it would most likely look like some sort of froth, perhaps living at the edge of the ocean, or deep in the ocean on a geothermal vent. At the molecular level, I'm sure it would have looked as complex and beautiful as modern life." link

Tuesday, May 11, 2010

Glupping Food Caused Gigantic Dinos

Biology of the sauropod dinosaurs: the evolution of gigantism. 2010. P. M. Sanders, et al. Biology Review, published Online: 29 Apr.

The Deutsche Forschungsgemeinschaft (German Research Foundation) has spent three million euros to find out that saurpods glupped their food, thus allowing them to reach gigantic sizes.
Chewing helps to digest the food faster. By the grinding process it is broken down and at the same time its surface is enlarged. This way the digestive enzymes are able to attack the food more easily.

'Chewing is a property of prototheria which no large herbivorous terrestrial mammal has got rid of,' Martin Sander says.

But chewing requires time – a resource that becomes scarce with increasing size. At the same time the following is true: the ones that chew need a large head, since molars and muscles have to be put somewhere. Not without reason elephants are quite big-headed. link

Born This Day: Doug Mclure

Greatest movie poster ever?
Actor Doug Mclure (May 11, 1935 – February 5, 1995) takes a bow here for playing Bowen Tyler in the film adaptations of Edgar Rice Burroughs books, At the Earth’s Core, The Land That Time Forgot, and The People That Time Forgot.

The Chemistry of Archaeopteryx

Archaeopteryx feathers and bone chemistry fully revealed via synchrotron imaging. 2010. U. Bergmann, et al. PNAS, published online before print May 10, 2010.

False color view of the Thermopolis Archaeopteryx. The image is a composite blend of scans of the elements phosphorus, silicon, sulfur, and iron. The bright colors in the wing areas show how part of the feather chemistry has been preserved. Image: K.G. Huntley/Stanford Synchrotron Radiation Lightsource
By recording how the X-rays interacted with the Thermopolis Archaeopteryx, researchers were able to identify very precisely the locations of chemical elements hidden within. From this, they created the first maps of the dinobird's chemistry, revealing half a dozen chemical elements that were actually part of the living animal itself. In almost every element studied, the researchers found significantly different concentrations in the fossil than in the rock that surrounds it, confirming that the observed elements are indeed remnants of the 'dinobird' and not merely chemicals that leached from the surrounding rock into the fossil.

The chemical maps show that portions of the feathers are not merely impressions of long-decomposed organic material—as was previously believed—but actual fossilized feathers that contain phosphorous and sulfur, elements that comprise modern bird feathers. Trace amounts of copper and zinc were also found in the 'dinobird's' bones; like birds today, the Archaeopteryx may have required these elements to stay healthy.

"We talk about the physical link between birds and dinosaurs, and now we have found a chemical link between them," said Roy Wogelius.. link

Friday, May 07, 2010

Neanderthal Genome Decoded

A Draft Sequence of the Neandertal Genome. 2010. Science 328: 710 – 722.

DNA signatures found in present-day Europeans and Asians, but not in Africans.
Researchers have produced the first whole genome sequence of the 3 billion letters in the Neanderthal genome, and the initial analysis suggests that up to 2 percent of the DNA in the genome of present-day humans outside of Africa originated in Neanderthals or in Neanderthals' ancestors.

The current fossil record suggests that Neanderthals, or Homo neanderthalensis, diverged from the primate line that led to present-day humans, or Homo sapiens, some 400,000 years ago in Africa. Neanderthals migrated north into Eurasia, where they became a geographically isolated group that evolved independently from the line that became modern humans in Africa. They lived in Europe and western Asia, as far east as southern Siberia and as far south as the Middle East.

Approximately 30,000 years ago, Neanderthals disappeared. That makes them the most recent, extinct relative of modern humans, as both Neanderthals and humans share a common ancestor from about 800,000 years ago. Chimpanzees diverged from the same primate line some 5 million to 7 million years ago.

To understand the genomic differences between present-day humans and Neanderthals, the researchers compared subtle differences in the Neanderthal genome to the genomes found in DNA from the five people, as well as to chimpanzee DNA. An analysis of the genetic variation showed that Neanderthal DNA is 99.7 percent identical to present-day human DNA, and 98.8 percent identical to chimpanzee DNA. Present-day human DNA is also 98.8 percent identical to chimpanzee.

"The genomic calculations showed good correlation with the fossil record," said coauthor Jim Mullikin. According to our results, the ancestors of Neanderthals and modern humans went their separate ways about 400,000 years ago. link

Died This Day: Skull Island Witch Doctor

Steve Clemente (born Esteban Clemento Morro Nov. 22, 1885—May 7, 1950) was a Mexican actor known for his many villainous roles. He began acting in his teens, signing up for his first movie, The Secret Man, in 1917. His later, numerous roles were usually bit parts and he was an expert knife thrower.

He was a known scene stealer and was famous for his villainous snarl. He later starred in such movies as The Most Dangerous Game (1932), playing Tartar, the second henchman of Count Zarrof and played the Witch King in King Kong (1933). From Wiki

Wednesday, May 05, 2010

Recreating Mammoth Hemoglobin: True Palaeobiology

Substitutions in woolly mammoth hemoglobin confer biochemical properties adaptive for cold tolerance. 2010. K. L. Campbel, et al. Nature Genetics, Published online 02 May 2010

A team of international researchers have recreated mammoth haemoglobin using ancient DNA preserved in bones from Siberian specimens 25,000 to 43,000 years old.
The team converted the mammoth haemoglobin DNA sequences into RNA, and inserted them into modern-day E. coli bacteria, which then manufactured the authentic mammoth protein.

Studies reveal special evolutionary adaptations that allowed the mammoth to cool its extremities down in harsh Arctic conditions to minimise heat loss.

"This is true palaeobiology, as we can study and measure how these animals functioned as if they were alive today."

"The resulting haemoglobin molecules are no different than 'going back in time' and taking a blood sample from a real mammoth," says Professor Campbell.

"We can now apply similar approaches to other extinct species, such as Australian marsupials," says team member Dr Jeremy Austin, who is currently using ancient DNA to study the evolution and extinction of the thylacine and Tasmanian Devil. link

Born This Day: Elkanah Billings

From Today In Science History:

Billings (May 5, 1820 - June 14, 1896) was a Canadian geologist and paleontologist, who was the first Canadian paleontologist.He published his first scientific paper on Trenton fossils in 1854. He launched a new monthly periodical, The Canadian Naturalist and Geologist in 1856, which he also edited and was the major contributor.

In Aug 1856 he was appointed staff paleontologist with the Canadian Geological Survey by William Edmond Logan, the founder of the Survey. Billings immediately began the task of identifying a 20-year backlog of fossils collected by the Survey. By 1863 he had published descriptions of no fewer than 526 new species of fossils.

The Billings medal, named in his honour, is awarded annually by the Paleontology Division of the Geological Association of Canada as a means of recognizing the most outstanding of its paleontologists.
On April 27, 1869, the Director of the GSC, Sir William Logan wrote this curt note to the paleontologist Elkanah Billings: "Your constant absence from the office is a worrying annoyance, particularly as I have reason to suspect that it does not arrive from rheumatism".
For more info on Billings click HERE.

Click HERE for more information on the Geological Association of Canada.

Portrait of Elkanah Billings GSC photo 69323 (c)

Monday, May 03, 2010

Nopcsa's Sauropod Dwarfs

Small body size and extreme cortical bone remodeling indicate phyletic dwarfism in Magyarosaurus dacus (Sauropoda: Titanosauria). 2010. K. Stein, et al. PNAS, Published online before print April 30.

Illo: Mihai Dumbrava,
In 1895, the sister of a eccentric palaeontologist Franz Baron Nopcsa discovered small dinosaur bones on their family estate in Transylvania. Nopcsa interpreted these as the remains of dwarfed animals that had once lived on an island. Among these finds were a number of bones belonging to a sauropod dinosaur which Nopcsa named Magyarosaurus dacus, after his native country. New research on the microanatomy of these bones prove that the little dinosaur was fully grown.

"Our study shows that dinosaurs on islands were subject to the same ecological and evolutionary processes that shape modern mammals," explains Martin Sander. "We were also able to demonstrate that the bigger bones found in that area belong to a different dinosaur species." Whether they come from stray animals who swam to the island from the mainland, or from large ancestors of the dwarf Magyarosaurus, remains a secret shrouded in the mists of pre-historic time. link

Sunday, May 02, 2010

Born This Day: Sir D'Arcy Thompson


D'Arcy Thompson (May 2, 1860 – June 21, 1948) was a British biologist whose masterwork, On Growth and Form, is a profound consideration of the shapes of living things, starting from the simple premise that "everything is the way it is because it got that way." Hence one must study not only finished forms, but also the forces that moulded them: "the form of an object is a 'diagram of forces', in this sense, at least, that from it we can judge of or deduce the forces that are acting or have acted upon it."

Now by "forces" Thompson meant forces, and one of his great themes is the tremendous light cast on living things by using mathematics to describe their shapes and fairly simple physics and chemistry to explain them. In other words, Thompson wrote a thousand page treatise on self-organization long before the word existed.
From Blackwell Publishing:
D'Arcy Thompson found that related species superficially looking very different could in some cases be represented as simple Cartesian transformations of one another. The most thoroughly worked out modern example of this is Raup's analysis of snail shell shapes with a morphospace.

With some simplification, the axes on the fish grids in here or the snails of the morphospace can be thought of as growth gradients. The evolutionary change between the species would then have been produced by a genetic change in the regulatory mechanisms controlling those gradients.

If we looked at these fish without the grids we might think that an evolutionary change from one into the other would be at least moderately complicated. The interest of D'Arcy Thompson's diagrams is then to show that shape changes could have been produced by heterochrony - a change in the rate or timing of development of some cell lines in the body relative to others.

Figure: a D'Arcy Thompson transformational diagram. The shapes of two species of fish have been plotted on Cartesian grids. Image from HERE.

Saturday, May 01, 2010

Published This Day: Species Plantarum by Linnaeus

In 1753, Carolus Linnaeus published the first edition of his Species Plantarum in which he gave systematic names to plants that are still in use today. He was the first to frame principles for defining genera and species of organisms and to create a uniform system for naming them. He is often called the father of classification, and he extended the familiar scheme of dual Latin names to identify animals in 1758. The Species Plantarum was taken by international consent in 1905 as the starting point for modern botanical nomenclature. From Today In Science History.