Feather diversity in the Barremian (Early Cretaceous) of Las Hoyas, Spain. 2011. J. Marugan-Lobon and R. Vullo. Comptes Rendus Palevol 10: 219-223.
Abstract: The preservation of feathers is a rare phenomenon in the fossil record. In this study, we report 11 isolated feathers from the Early Cretaceous of the Konservat-Lagerstätte of Las Hoyas, Spain. Most of them are preserved as a carbonised thin layer, but there are also imprints. The specimens are relatively small, and unambiguously correspond to body contour feathers, although it is very difficult to match them to a particular taxon (among avian or non-avian theropods).
Among the fossils, there is an almost complete remige, a well-preserved fragment of a possible ornamental rectrice feather, and possibly a semiplume. Furthermore, some specimens appear to have different colour patterns, such as stripes or patches.
Senin, 30 Mei 2011
Sabtu, 28 Mei 2011
Born This Day: Louis Agassiz
(Jean) Louis (Rodolphe) Agassiz (May 28, 1807 - Dec. 14, 1873) 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
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
Jumat, 27 Mei 2011
Died 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.
Arbogast on Film blog has nice appreciation of Sandra Shaw’s few famous film moments.
An Ordovician Anomalocaridid
A giant Ordovician anomalocaridid. 2010. P. Van Roy and. E.G. Briggs. Nature 473: 510–513.
Fossils from this period suggested these marine predators grew to be about two feet long. Until now, scientists also thought these strange invertebrates—which had long spiny head limbs presumably used to snag worms and other prey, and a circlet of plates around the mouth—died out at the end of the Cambrian.
The anomalocaridid fossils reveal a series of blade like filaments in each segment across the animal's back, which scientists think might have functioned as gills.
The specimens are just part of a new trove of fossils from Morocco that includes thousands of examples of soft-bodied marine fauna dating back to the early Ordovician period, 488 to 472 million years ago. The animals found in Morocco inhabited a muddy sea floor in fairly deep water, and were trapped by sediment clouds that buried them and preserved their soft bodies. link
Scientists have discovered a giant fossilized anomalocaridid from the Ordovician that measures one meter in length meaning these animals existed for 30 million years longer than previously realized.Anomalocaridids were the largest animals of the Cambrian period, known for the "Cambrian Explosion" that saw the sudden appearance of all the major animal groups and the establishment of complex ecosystems about 540 to 500 million years ago.
Fossils from this period suggested these marine predators grew to be about two feet long. Until now, scientists also thought these strange invertebrates—which had long spiny head limbs presumably used to snag worms and other prey, and a circlet of plates around the mouth—died out at the end of the Cambrian.
The anomalocaridid fossils reveal a series of blade like filaments in each segment across the animal's back, which scientists think might have functioned as gills.
The specimens are just part of a new trove of fossils from Morocco that includes thousands of examples of soft-bodied marine fauna dating back to the early Ordovician period, 488 to 472 million years ago. The animals found in Morocco inhabited a muddy sea floor in fairly deep water, and were trapped by sediment clouds that buried them and preserved their soft bodies. link
Selasa, 24 Mei 2011
Born This Day: William Whewell
Whewell (May 24, 1846 - Feb. 23, 1934) was a British scientist, best known for his survey of the scientific method and for creating scientific words. He founded mathematical crystallography and developed Mohr's classification of minerals.
He created the words scientist and physicist by analogy with the word artist. They soon replaced the older term natural philosopher. Other useful words were coined to help his friends: biometry for Lubbock; Eocine, Miocene and Pliocene for Lyell; and for Faraday, anode, cathode, diamagnetic, paramagnetic, and ion (whence the sundry other particle names ending -ion).
In metereology, Whewell devised a self-recording anemometer. He was second only to Newton for work on tidal theory. He died as a result of being thrown from his horse. From Today In Science History.
He created the words scientist and physicist by analogy with the word artist. They soon replaced the older term natural philosopher. Other useful words were coined to help his friends: biometry for Lubbock; Eocine, Miocene and Pliocene for Lyell; and for Faraday, anode, cathode, diamagnetic, paramagnetic, and ion (whence the sundry other particle names ending -ion).
In metereology, Whewell devised a self-recording anemometer. He was second only to Newton for work on tidal theory. He died as a result of being thrown from his horse. From Today In Science History.
Minggu, 22 Mei 2011
Fossil Hunting at Lyme Regis
Mary Anning isn't the only one to have found fossils in the Lyme Regis area.
These photos show Paddy Howe, the geologist at the Lyme Regis Museum, and some friends fossil hunting on the blue lias ledges. What they found was this partial icthyosaur pabble. Very cool!
Get more info at the Lyme Regis Museum blog.
These photos show Paddy Howe, the geologist at the Lyme Regis Museum, and some friends fossil hunting on the blue lias ledges. What they found was this partial icthyosaur pabble. Very cool!
Get more info at the Lyme Regis Museum blog.
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.
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.
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
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
Sabtu, 21 Mei 2011
Born 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.
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.
Jumat, 20 Mei 2011
Fossil Evidence on Origin of the Mammalian Brain
Fossil Evidence on Origin of the Mammalian Brain. 2011. T. Rowe, et al. Science 332: 955-957.
CT scans indicate that the nasal cavity and related smell regions were enlarged in the pre-mammal fossils, along with areas of the brain that process olfactory information. Both characteristics indicate an improved sense of smell in pre-mammals.
The study also looked at the influence of body hair development on brain size. For example, the paper clip-sized Hadrocodium sported fur, and evidence from fossilized pelts or skin of closely related animals hints that Morganuocodon likely had hair too. The authors speculate that hairy early mammals were quick to develop a keen sense of touch or tactile sensitivity, along with enhanced motor coordination.
Rather than being used for warmth, body hairs initially served as tiny air traffic controllers, allowing pre-mammals to navigate small crevices and avoid harm. This heightened tactile sensitivity eventually lead to the formation of intricate sensory fields in the neocortex of mammalian brain, the authors propose.
In both fossils, the size of the cerebellum (the region of the brain responsible for sensory-motor integration) grew so large it began to ripple over into folds; this increase in size supports the idea that early mammals developed advanced neuromuscular coordination. link
Mammals first evolved their characteristic large brains to enable a stronger sense of smell, according to a new study.By reconstructing fossils of two Early Jurassic Period mammals--Morganuocodon and Hadrocodium--the authors provide new evidence that the mammalian brain evolved in three major stages: first by improvements in sense of smell or olfaction; next by an increase in touch or tactile sensitivity from body hair; and third by improved neuromuscular coordination or the ability to produce skilled muscle movement using the senses.
CT scans indicate that the nasal cavity and related smell regions were enlarged in the pre-mammal fossils, along with areas of the brain that process olfactory information. Both characteristics indicate an improved sense of smell in pre-mammals.
The study also looked at the influence of body hair development on brain size. For example, the paper clip-sized Hadrocodium sported fur, and evidence from fossilized pelts or skin of closely related animals hints that Morganuocodon likely had hair too. The authors speculate that hairy early mammals were quick to develop a keen sense of touch or tactile sensitivity, along with enhanced motor coordination.
Rather than being used for warmth, body hairs initially served as tiny air traffic controllers, allowing pre-mammals to navigate small crevices and avoid harm. This heightened tactile sensitivity eventually lead to the formation of intricate sensory fields in the neocortex of mammalian brain, the authors propose.
In both fossils, the size of the cerebellum (the region of the brain responsible for sensory-motor integration) grew so large it began to ripple over into folds; this increase in size supports the idea that early mammals developed advanced neuromuscular coordination. link
Born This Day: Edward B. Lewis
Lewis (May 20, 1918 - July 21, 2004) was an American developmental geneticist who was awarded the 1995 Nobel Prize for Physiology or Medicine for discovering the functions that control early embryonic development with co-winners Christiane Nüsslein-Volhard and Eric F. Wieschaus. They identified and classified 15 key genes that determine the body plan and formation of body segments of the fruit fly Drosophila melanogaster.
Lewis studied the next step, the homeotic genes that govern the development of a larval segment into a specific body segment. Lewis found a co-linearity in time and space between the order of the genes in the bithorax complex and their effect regions in the segments. From Today In Science History
Lewis studied the next step, the homeotic genes that govern the development of a larval segment into a specific body segment. Lewis found a co-linearity in time and space between the order of the genes in the bithorax complex and their effect regions in the segments. From Today In Science History
Xilousuchus is An Archosaur
A sail-backed suchian from the Heshanggou Formation (Early Triassic: Olenekian) of China. 2011. S. Nesbitt, et al. Earth and Environmental Science Transactions of the Royal Society of Edinburgh 101: 271-284.
The only known specimen of the 247 million year old Xilousuchus sapingensis has been reclassified as an archosaur. The specimen – a skull and 10 vertebrae – was found in the Heshanggou Formation in northern China.
The fossil was originally classified as an archosauriform, a "cousin" of archosaurs, rather than a true archosaur, but that was before the discovery of more complete early archosaur specimens from other parts of the Triassic period. The researchers examined bones from the specimen in detail, comparing them to those from the closest relatives of archosaurs, and discovered that X. sapingensis differed from virtually every archosauriform.
Among their findings was that bones at the tip of the jaw that bear the teeth likely were not downturned as much as originally thought when the specimen was first described in the 1980s. They also found that neural spines of the neck formed the forward part of a sail similar to that found on another ancient archosaur called Arizonasaurus, a very close relative of Xilousuchus found in Arizona.
The new research places X. sapingensis firmly within the archosaur family tree, providing evidence that the early members of the crocodile and bird family trees evolved earlier than previously thought. link
The only known specimen of the 247 million year old Xilousuchus sapingensis has been reclassified as an archosaur. The specimen – a skull and 10 vertebrae – was found in the Heshanggou Formation in northern China.
The fossil was originally classified as an archosauriform, a "cousin" of archosaurs, rather than a true archosaur, but that was before the discovery of more complete early archosaur specimens from other parts of the Triassic period. The researchers examined bones from the specimen in detail, comparing them to those from the closest relatives of archosaurs, and discovered that X. sapingensis differed from virtually every archosauriform.
Among their findings was that bones at the tip of the jaw that bear the teeth likely were not downturned as much as originally thought when the specimen was first described in the 1980s. They also found that neural spines of the neck formed the forward part of a sail similar to that found on another ancient archosaur called Arizonasaurus, a very close relative of Xilousuchus found in Arizona.
The new research places X. sapingensis firmly within the archosaur family tree, providing evidence that the early members of the crocodile and bird family trees evolved earlier than previously thought. link
This article is from a special issue of Earth and Environmental Science Transactions of the Royal Society of Edinburgh on Late Triassic Terrestrial Biotas and the Rise of Dinosaurs.
Died This Day: Stephen Jay Gould
Here’s a nice piece on Gould by Henry Lowood from the Stanford Presidential Lectures in the Humanities and Arts.
Kamis, 19 Mei 2011
Conodont Feeding Model
Synchrotron-aided reconstruction of the conodont feeding apparatus and implications for the mouth of the first vertebrates. 2011. N. Goudemand, et al. PNAS early edition.
A fang-like tooth on double upper lips, spiny teeth on the tongue and a pulley-like mechanism to move the tongue backwards and forwards – this bizarre bite belongs to a conodont and, thanks to a fresh fossil find, has now been analyzed and reconstructed to show how the first vertebrates fed.
Most conodonts had to have two upper lips, upon each of which there was a long, fang-like structure. The conodonts also had a kind of tongue bearing a complex set of spiny or comb-like ‘teeth’. The ‘tongue’ rested on pulley-like cartilage and could be moved backwards and forwards thanks to two opposing muscles. The conodonts used the ‘tongue’ and lips to grab food before two pairs of relatively robust, sometimes molar-like ‘throat teeth’ ground and cut it up.
The conodonts’ unique feeding mechanism is fairly similar to that of the extant lamprey, which is widely regarded as the extinct conodonts’ nearest relative. Due to the comparative feeding mechanism and other similarities, lampreys and conodonts must have a common ancestor which was one of the first vertebrates. This common ancestor must also have had a tongue mounted on pulley-like cartilage and therefore eaten in the same manner as the conodonts. link
A fang-like tooth on double upper lips, spiny teeth on the tongue and a pulley-like mechanism to move the tongue backwards and forwards – this bizarre bite belongs to a conodont and, thanks to a fresh fossil find, has now been analyzed and reconstructed to show how the first vertebrates fed.
Most conodonts had to have two upper lips, upon each of which there was a long, fang-like structure. The conodonts also had a kind of tongue bearing a complex set of spiny or comb-like ‘teeth’. The ‘tongue’ rested on pulley-like cartilage and could be moved backwards and forwards thanks to two opposing muscles. The conodonts used the ‘tongue’ and lips to grab food before two pairs of relatively robust, sometimes molar-like ‘throat teeth’ ground and cut it up.
The conodonts’ unique feeding mechanism is fairly similar to that of the extant lamprey, which is widely regarded as the extinct conodonts’ nearest relative. Due to the comparative feeding mechanism and other similarities, lampreys and conodonts must have a common ancestor which was one of the first vertebrates. This common ancestor must also have had a tongue mounted on pulley-like cartilage and therefore eaten in the same manner as the conodonts. link
The Origin of Amphisbaenians
Eocene lizard from Germany reveals amphisbaenian origins. 2010. J. Muller, et al. Nature 473: 364–367.
Genetic studies suggest that snakes are related to monitor lizards and iguanas, while their anatomy points to amphisbaenians ("worm lizards"), a group of burrowing lizards with snake-like bodies. A recent discovery of a tiny, 47 million-year-old fossil of a lizard called Cryptolacerta hassiaca provides the first anatomical evidence that the body shapes of snakes and limbless lizards evolved independently.
The fossil reveals that amphisbaenians are not closely related to snakes, but instead are related to lacertids, a group of limbed lizards from Europe, Africa and Asia.
A analysis using both anatomical and molecular data shows that Cryptolacerta shared a thickened, reinforced skull with worm lizards and that both were most closely related to lacertids, while snakes were related to monitor lizards like the living Komodo dragons. link
Genetic studies suggest that snakes are related to monitor lizards and iguanas, while their anatomy points to amphisbaenians ("worm lizards"), a group of burrowing lizards with snake-like bodies. A recent discovery of a tiny, 47 million-year-old fossil of a lizard called Cryptolacerta hassiaca provides the first anatomical evidence that the body shapes of snakes and limbless lizards evolved independently.
The fossil reveals that amphisbaenians are not closely related to snakes, but instead are related to lacertids, a group of limbed lizards from Europe, Africa and Asia.
A analysis using both anatomical and molecular data shows that Cryptolacerta shared a thickened, reinforced skull with worm lizards and that both were most closely related to lacertids, while snakes were related to monitor lizards like the living Komodo dragons. link
It's not closely related to ankylosaurs, either.
Born This Day: William King Gregory
William King Gregory (May, 19 1876 – Dec. 29, 1970) was an American zoologist and paleontologist who studied under Henry Fairfield Osborn and joined the American Museum of Natural History in 1911. As a professor at Columbia University one of his students was Alfred Sherwood Romer. His work charted the evolution from the early fishes through the various branches to birds and mammals, with numerous papers and two important books: Our Face from Fish to Man (1929) and Evolution Emerging (1951).
In the early 1920s he also became interested in recent human evolution and joined the Central Asiatic Expedtions lead by Roy Chapman Andrews whose original goal was to find evidence of human ancestors in the Gobi Desert. With C.C. Mook he wrote the paper, On Protoceratops, a primative ceratopsian dinosaur from the Lower Cretaceous of Mongolia and well as numerous papers on Cretaceous mammals.
Gregory wrote a number of popular articles on evolution and fossils that you find through the Google Books on-line archive of old magazines.
In the early 1920s he also became interested in recent human evolution and joined the Central Asiatic Expedtions lead by Roy Chapman Andrews whose original goal was to find evidence of human ancestors in the Gobi Desert. With C.C. Mook he wrote the paper, On Protoceratops, a primative ceratopsian dinosaur from the Lower Cretaceous of Mongolia and well as numerous papers on Cretaceous mammals.
Gregory wrote a number of popular articles on evolution and fossils that you find through the Google Books on-line archive of old magazines.
Born This Day Carl Akeley
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.
Selasa, 17 Mei 2011
Scopes Monkey Trial Law Repealed
On this day in 1967, the governor of Tennessee signed into law the repeal of the 1925 state law prohibiting the teaching of evolution.From Today In Science History
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.
Minggu, 15 Mei 2011
Excavating Ghost Ranch
Greg McDonald generously passed along these photos from 1982 taken during the Ghost Ranch excavations that lead to a number of blocks from the Coelophysis quarry being distributed to museums across the country.
Born This Day: Clarence Edward Dutton
Dutton (May 15, 1841 - Jan. 4, 1912) was an American geologist who in 1887 was put in charge of the division of volcanic geology and seismology. His investigation of the Charleston earthquake of 1886, published in the reports of that survey, attracted wide attention and helped to develop scientific interest in the study of earthquake phenomena. He is acknowedged as being the pioneer seismologist who developed and named the principle of isostasy. From Wikipedia
Published This Day: The Recipe For Primordial Soup
In 1953, Stanley L. Miller's paper on the synthesis of amino acids under conditions that simulated primitive Earth's atmosphere was published in Science.
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. 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. From Today in Science History.
Sabtu, 14 Mei 2011
Born This Day: James Flavin
Flavin (May 14, 1906 – April 23, 1976) starred in his first film (The Airmail Mystery) in 1932. After that he played mostly supporting characters in nearly four hundred films between 1932 and 1971, and in almost a hundred television episodes. He takes a bow here for playing Second Mate Briggs in King Kong (1933)
Pangaean Reptiles Were All Wet
Climatically driven biogeographic provinces of Late Triassic tropical Pangea. 2011. J. Whiteside, et al. PNAS, Published online before print May 13.
More than 200 million years ago, mammals and reptiles lived in their own separate worlds on the supercontinent Pangaea, despite little geographical incentive to do so. Mammals lived in areas of twice-yearly seasonal rainfall; reptiles stayed in areas where rains came just once a year. Mammals lose more water when they excrete, and thus need water-rich environments to survive. link
More than 200 million years ago, mammals and reptiles lived in their own separate worlds on the supercontinent Pangaea, despite little geographical incentive to do so. Mammals lived in areas of twice-yearly seasonal rainfall; reptiles stayed in areas where rains came just once a year. Mammals lose more water when they excrete, and thus need water-rich environments to survive. link
Jumat, 13 Mei 2011
Died This Day: Georges Cuvier
“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.
Read about him at the University of California Museum of Paleontology.
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