de Beer (Nov. 1, 1899 – June 21, 1972) was an English zoologist and morphologist who contributed to experimental embryology, anatomy, and evolution. He refuted the germ-layer theory and developed the concept of paedomorphism - the retention of juvenile characteristics of ancestors in mature adults).
From examination of the fossil
Archaeopteryx, De Beer proposed mosaic evolution with piecemeal evolutionary changes to explain the combination of bird and reptile features.
From Today In Science History.
Senin, 21 Juni 2010
Rabu, 16 Juni 2010
Born This Day: George Gaylord Simpson
"Life is the most important thing about the world, the most important thing about life is evolution. Thus, by consciously seeking what is most meaningful, I moved from poetry to mineralogy to paleontology to evolution." G.G. SimpsonFrom the web site supporting the excellent PBS show “Evolution”:
As one of the founders of the "modern synthesis" of evolution, paleontologist George Gaylord Simpson (June 16, 1902 - Oct 6, 1984) argued that the fossil record supports Darwin's theory that natural selection acting on random variation in a population is the driving force behind evolution. Simpson was among the first to use mathematical methods in paleontology, and he also took into account newly discovered genetic evidence for evolution in his study of paleontology.
In his 1944 book, Tempo and Mode in Evolution, Simpson divided evolutionary change into "tempo," the rate of change, and "mode," the manner or pattern of change, with tempo being a basic factor of mode. Simpson saw paleontology, revealing the long history of life on earth, as a unique field through which to study the history of evolution.
The early part of the twentieth century saw evolutionary theory embattled by disagreements over Darwin's emphasis on natural selection. The then-newly rediscovered work of Gregor Mendel in the nineteenth century was an uncomfortable fit with evolution, as many scientists saw it. They weren't at all certain that natural populations contained enough genetic variation for natural selection to create new species. So they entertained other explanations, including inheritance of acquired characteristics, "directed" variation toward a goal, or sudden large mutations that resulted in new species.
In the field of paleontology, the scientist who did most to resolve these questions was George Gaylord Simpson, who was on the staff of the American Museum of Natural History for 30 years.At a time when other paleontologists were convinced that the fossil record could best be explained by directed variation, Simpson disagreed. He said that fossil patterns needed no mystical or goal-oriented processes to explain them. For example, where others saw the modern horse as having arisen in a single advance toward the specialized form, Simpson saw the path as that of an irregular tree that had many side-branches leading off to extinction.
Simpson argued that the evolution of mammals, as seen in their fossilized remains, fit perfectly well with the new mechanisms of population genetics being studied at the time. He used the then-new mathematical methods to clarify how evolution occurred in "gene pools" in populations, not in individual members of the population.
Importantly, he showed that gaps in the fossil record reflected periods of substantial change through rapid "quantum evolution" in small populations, leaving little fossil evidence behind. At other times, he observed, rates of change could be so slow as to seem almost nonexistent.
Read more about Simpson HERE.
FYI, I'm now, more or less, in the field for the summer. I'll post when I can, and will, hopefully, have lots of field photos for the blog.
Senin, 14 Juni 2010
Ojoceratops fowleri
Ojoceratops fowleri, one of the largest known horned dinosaurs, was discovered in 2005 by Montana State University Ph.D. student Denver Fowler in the Four Corners area in the Bisti/De-Na-Zin Wilderness.
The discovery of the Ojoceratops bones, the events surrounding it and the details about the new ceratopsid dinosaur were released Thursday in a study published in the book New Perspectives On Horned Dinosaurs.
"Ojoceratops is a very distinctive beast," Robert M. Sullivan, senior curator of paleontology and geology at the State Museum of Pennsylvania, said in a news released issued by the New Mexico Museum of Natural History & Science. Sullivan led the series of expeditions to recover the bones.
Sullivan described the dinosaur in the Patriot-News on Tuesday as a three-horned vegetarian bigger than a hippopotamus and smaller than an elephant, about 17 to 20 feet in length.
"Based on other bones, such as the lower jaw and predentary, found in the same rock formation, Ojoceratops rivaled the size of Torosaurus and some of the larger specimens of Triceratops," Lucas said. From: The Santa Fe New Mexican
Warm-Blooded Mesozoic Marine Reptiles
Regulation of Body Temperature by Some Mesozoic Marine Reptiles. 2010. A. Bernard, et al. Science 328: 1379 – 1382.
Abstract: What the body temperature and thermoregulation processes of extinct vertebrates were are central questions for understanding their ecology and evolution. The thermophysiologic status of the great marine reptiles is still unknown, even though some studies have suggested that thermoregulation may have contributed to their exceptional evolutionary success as apex predators of Mesozoic aquatic ecosystems.
We tested the thermal status of ichthyosaurs, plesiosaurs, and mosasaurs by comparing the oxygen isotope compositions of their tooth phosphate to those of coexisting fish. Data distribution reveals that these large marine reptiles were able to maintain a constant and high body temperature in oceanic environments ranging from tropical to cold temperate.
Their estimated body temperatures, in the range from 35°±2°C to 39°±2°C, suggest high metabolic rates required for predation and fast swimming over large distances offshore.
Abstract: What the body temperature and thermoregulation processes of extinct vertebrates were are central questions for understanding their ecology and evolution. The thermophysiologic status of the great marine reptiles is still unknown, even though some studies have suggested that thermoregulation may have contributed to their exceptional evolutionary success as apex predators of Mesozoic aquatic ecosystems.
We tested the thermal status of ichthyosaurs, plesiosaurs, and mosasaurs by comparing the oxygen isotope compositions of their tooth phosphate to those of coexisting fish. Data distribution reveals that these large marine reptiles were able to maintain a constant and high body temperature in oceanic environments ranging from tropical to cold temperate.
Their estimated body temperatures, in the range from 35°±2°C to 39°±2°C, suggest high metabolic rates required for predation and fast swimming over large distances offshore.
Died 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.
Click HERE for more information on the Geological Association of Canada.
Portrait of Elkanah Billings GSC photo 69323 (c)
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)
Minggu, 13 Juni 2010
Premiered This Day: The Beast From 20,000 Fathoms
Directed by Eugène Lourié, this was Ray Harryhausen’s first solo film after having finished his apprenticeship with Willis O’Brien on Mighty Joe Young. Apparently the dinosaur skeleton in the museum sequence was the same one used in Bringing Up Baby.
Born This Day: Luis Alvarez
Alvarez (June 13, 1911 - Sept. 1, 1988) was an American experimental physicist who was awarded the Nobel Prize for Physics in 1968 for work that included the discovery of many resonance particles --subatomic particles having extremely short lifetimes and occurring only in high-energy nuclear collisions.
In about 1980 Alvarez (left) helped his son, the geologist Walter Alvarez (right), publicize Walter's discovery of a worldwide layer of clay that has a high iridium content and which occupies rock strata at the geochronological boundary between the Mesozoic and Cenozoic eras; i.e., about 66.4 million years ago. They postulated that the iridium had been deposited following the impact on Earth of an asteroid or comet and that the catastrophic climatic effects of this massive impact caused the extinction of the dinosaurs.
Though initially controversial, this widely publicized theory gradually gained support as the most plausible explanation of the abrupt demise of the dinosaurs.
Read more HERE. Image from HERE.
In about 1980 Alvarez (left) helped his son, the geologist Walter Alvarez (right), publicize Walter's discovery of a worldwide layer of clay that has a high iridium content and which occupies rock strata at the geochronological boundary between the Mesozoic and Cenozoic eras; i.e., about 66.4 million years ago. They postulated that the iridium had been deposited following the impact on Earth of an asteroid or comet and that the catastrophic climatic effects of this massive impact caused the extinction of the dinosaurs.
Though initially controversial, this widely publicized theory gradually gained support as the most plausible explanation of the abrupt demise of the dinosaurs.
Read more HERE. Image from HERE.
Kamis, 10 Juni 2010
Dinosaur Hunting by Boat in Alberta
2010 marks the 100th anniversary of the first scow-based dinosaur-hunting expeditions in Alberta, Canada. These flat-bottomed boats were used by Barnum Brown of the American Museum of Natural History as floating field camps between 1910 and 1913. When Brown left Canada, the Sternberg family of dinosaur hunters, working for the Geological Survey of Canada, also used them from 1913-1916.
Royal Tyrrell Museum technician, Darren Tanke, has for the past 8 years been working towards a Centennial re-enactment of the first AMNH trip, making and equipping a 1:1 scale of the AMNH scow. In late June of this year he and a dedicated crew will launch their scow (the Peter C. Kaisen; named after a Barnum Brown assistant) from the city of Red Deer, Alberta, and over a 5 week period float down the Red Deer River, ending in Dinosaur Provincial Park around August 7th. Along the way they'll be looking for dinosaur fossils and reliving history.
The blog 2010 Dino Hunting By Boat details the scow’s construction and the trip.
Rabu, 09 Juni 2010
Dinosaur Eggs & Babies: Remarkable Fossils from South Africa
Dr. David Evans is curating the new exhibit, "Dinosaur Eggs & Babies: Remarkable Fossils from South Africa," running until July 4 at the Royal Ontatio Museum, showcaseing the oldest fossilized dinosaur eggs and embryos ever uncovered.
Read the story HERE. More info at the ROM.
Read the story HERE. More info at the ROM.
Ken Carpenter - New Director of the Prehistoric Museum in Price
Paleontologist Ken Carpenter, a curator at the Denver Museum of Nature and Science, takes over this month as director of the Prehistoric Museum in Price, Utah.
Read the story HERE
Human Ancestors Lived in Hot Environments
High-temperature environments of human evolution in East Africa based on bond ordering in paleosol carbonates. 2010. B. Passey, et al. PNAS, pub. 0n-line June 8.
East Africa's Turkana Basin has been a hot savanna region for at least the past 4 million years—including the period of time during which early hominids evolved in this area. The findings are based on measurements of the spatial distribution and concentrations of isotopes in carbonate ions in the ancient soils.
The findings also shed some light—and heat—on a longstanding debate over the origin of bipedalism in early humans.
"For a long time, anthropologists have hypothesized that bipedalism and other unique human traits would be advantageous to life in hot savanna environments," says Passey. "For example, by standing upright, we intercept less direct sunlight than if we were on all fours, and in hot, open environments, the ground and near-surface air can be appreciably hotter than the air a few feet above the ground. So, by standing upright, we are avoiding a high-temperature environment."
Of course, Passey adds, this strategy would only be of significant use if the environment in question is indeed a high-temperature one. "In cooler environments, these traits do not really have a thermal advantage," he notes. These considerations led to the team's interest in figuring out just how hot it was in the part of the world where bipedalism is most likely to have first gained a toehold. link
East Africa's Turkana Basin has been a hot savanna region for at least the past 4 million years—including the period of time during which early hominids evolved in this area. The findings are based on measurements of the spatial distribution and concentrations of isotopes in carbonate ions in the ancient soils.
The findings also shed some light—and heat—on a longstanding debate over the origin of bipedalism in early humans.
"For a long time, anthropologists have hypothesized that bipedalism and other unique human traits would be advantageous to life in hot savanna environments," says Passey. "For example, by standing upright, we intercept less direct sunlight than if we were on all fours, and in hot, open environments, the ground and near-surface air can be appreciably hotter than the air a few feet above the ground. So, by standing upright, we are avoiding a high-temperature environment."
Of course, Passey adds, this strategy would only be of significant use if the environment in question is indeed a high-temperature one. "In cooler environments, these traits do not really have a thermal advantage," he notes. These considerations led to the team's interest in figuring out just how hot it was in the part of the world where bipedalism is most likely to have first gained a toehold. link
Selasa, 08 Juni 2010
Died This Day: Ruth Rose
Ruth Rose (Jan. 16, 1896 - June 8, 1978) was the daughter of Edward E. Rose. In 1926 she meet (and later married) cinematographer Ernest Schoedsack when they were both working on a New York Geological Society expedition to the Galapagos Islands. Together with partner and fellow producer director, Meriam C. Cooper, and animator Willis O’Brien, they made “King Kong”, released in 1933. Rose shared in many of Schoedsack’s and Cooper’s wildness film productions, and worked as a writer or script doctor on King Kong, Son of Kong, She, The Last Days of Pompeii and Mighty Joe Young.
The photo from King Kong (above) is of Bruce Cabot, Fay Wray and Robert Armstrong, but Rose clearly modeled the characters they played after Schoedsack, herself, and Cooper.
The photo from King Kong (above) is of Bruce Cabot, Fay Wray and Robert Armstrong, but Rose clearly modeled the characters they played after Schoedsack, herself, and Cooper.
Born This Day: Francis Crick
From Today In Science History:
Crick (June 8, 1916 – July 28, 2004) was a British biophysicist, who, with James Watson and Maurice Wilkins, received the 1962 Nobel Prize for Physiology or Medicine for their determination of the molecular structure of deoxyribonucleic acid (DNA), the chemical substance ultimately responsible for hereditary control of life functions.
Crick and Watson began their collaboration in 1951, and published their paper on the double helix structure on April 2, 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.
Crick (June 8, 1916 – July 28, 2004) was a British biophysicist, who, with James Watson and Maurice Wilkins, received the 1962 Nobel Prize for Physiology or Medicine for their determination of the molecular structure of deoxyribonucleic acid (DNA), the chemical substance ultimately responsible for hereditary control of life functions.
Crick and Watson began their collaboration in 1951, and published their paper on the double helix structure on April 2, 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.
Senin, 07 Juni 2010
Born This Day: William Conybeare
From Today In Science History:
Conybeare (June 7, 1787 - August 12, 1857) was an English clergyman, geologist and paleontologist, known for his classic work, with co-author, William Phillips, on the stratigraphy of the Carboniferous (280-345 million years ago) System in England and Wales, Outline of the Geology of England and Wales (1822), one of the most influential textbooks on stratigraphy of the period.
He also described and reconstructed saurian fossils from the Lyme Regis area of England. He wrote the first monograph on the ichthyosaur, drawing it as a lizard with paddle-like limbs. In 1821 he described the skeleton of the plesiosaurus. As a friend and collaborator of William Buckland, Conybeare was an influential member of the Oxford School of Geology. portrait
Conybeare (June 7, 1787 - August 12, 1857) was an English clergyman, geologist and paleontologist, known for his classic work, with co-author, William Phillips, on the stratigraphy of the Carboniferous (280-345 million years ago) System in England and Wales, Outline of the Geology of England and Wales (1822), one of the most influential textbooks on stratigraphy of the period.
He also described and reconstructed saurian fossils from the Lyme Regis area of England. He wrote the first monograph on the ichthyosaur, drawing it as a lizard with paddle-like limbs. In 1821 he described the skeleton of the plesiosaurus. As a friend and collaborator of William Buckland, Conybeare was an influential member of the Oxford School of Geology. portrait
BP.O.'d
Pete Von Sholly sent along the above cartoon a while back. He also has a new 'on-blog-only' dinosaur book (see below) up on his blog VonShollywood.com.
Kamis, 03 Juni 2010
Born This Day: James Hutton
Hutton (June 3, 1726 - March 26, 1797) is considered to be the father of modern geology. He is accredited with proposing that observed geologic processes have been occurring at a uniform rate since the creation of earth, also know as the theory of unconformities. This led to his controversial suggestion that the earth is incredibly old.
Hutton began to notice geologic processes on his land in the 1750’s by following his soil during rainstorms when it would erode into the sea. He also noticed how long the process took and began to apply this idea to other parts of geology. If it took this long for some soil to move a few miles than how long did it take to form the cliffs by the sea? He also took note of other features in the landscape such as angular unconformities. A breakthrough point occurred for Hutton when he found Siccar’s Point. This site shows the build up of sediment over a long period of time as well as other geologic processes. It was this idea of continuous processes that fascinated Hutton for the rest of his life.
Hutton subsequently moved back to Edinburgh, and became very involved with the Royal Society of Edinburgh. In 1785 he had his friend Joseph Black read his lecture on his theories of earth. This was the first time that his full theory had been made public. He was met with much anger and rejection. Even though we take his ideas for granted today, at the time he was presenting this the oldest proposed age of earth was around six thousand years, as laid forth by the church. While he was able to convince a few by showing them prime field examples such as Glen Tilt and Siccar’s Point, for many it remained too radical an idea to consider.
Text modified from HERE. Image from HERE.
Hutton began to notice geologic processes on his land in the 1750’s by following his soil during rainstorms when it would erode into the sea. He also noticed how long the process took and began to apply this idea to other parts of geology. If it took this long for some soil to move a few miles than how long did it take to form the cliffs by the sea? He also took note of other features in the landscape such as angular unconformities. A breakthrough point occurred for Hutton when he found Siccar’s Point. This site shows the build up of sediment over a long period of time as well as other geologic processes. It was this idea of continuous processes that fascinated Hutton for the rest of his life.
Hutton subsequently moved back to Edinburgh, and became very involved with the Royal Society of Edinburgh. In 1785 he had his friend Joseph Black read his lecture on his theories of earth. This was the first time that his full theory had been made public. He was met with much anger and rejection. Even though we take his ideas for granted today, at the time he was presenting this the oldest proposed age of earth was around six thousand years, as laid forth by the church. While he was able to convince a few by showing them prime field examples such as Glen Tilt and Siccar’s Point, for many it remained too radical an idea to consider.
Text modified from HERE. Image from HERE.
Rabu, 02 Juni 2010
Born This Day: Clair Cameron Patterson
From Today In Science History:
Patterson (June 2, 1922 - December 5, 1995) was a U.S. geochemist who in 1953 made the first precise measurement of the Earth's age, 4.55 billion years. He is noted for providing the first reliable ages of the earth and meteorites (1962), using analysis of the isotopic compositions and concentrations of lead in terrestrial materials and meteorites.
He also established the patterns of isotopic evolution of lead on earth, by analysis of critical rocks, sediments and waters of the planet. Thus he created a powerful tool for identifying, tracing and evaluating the nature of the major geochemical reservoirs in the crust, mantle, and oceans.
Photo from HERE.
Patterson (June 2, 1922 - December 5, 1995) was a U.S. geochemist who in 1953 made the first precise measurement of the Earth's age, 4.55 billion years. He is noted for providing the first reliable ages of the earth and meteorites (1962), using analysis of the isotopic compositions and concentrations of lead in terrestrial materials and meteorites.
He also established the patterns of isotopic evolution of lead on earth, by analysis of critical rocks, sediments and waters of the planet. Thus he created a powerful tool for identifying, tracing and evaluating the nature of the major geochemical reservoirs in the crust, mantle, and oceans.
Photo from HERE.
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