Died This Day: Stephen Jay Gould

Sept. 10, 1941 - May 20. 2002

Here’s a nice piece on Gould by Henry Lowood from the Stanford Presidential Lectures in the Humanities and Arts.

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

The Origin of Amphisbaenians

Eocene lizard from Germany reveals amphisbaenian origins. 2010. J. Muller, et al. Nature 473: 364–367.

Talking Snake, Tiger Pirates & Kamandi © DC Comics

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

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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.

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.

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.

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.

From Today In Science History

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.

CLICK TO ENLARGE














L to R: Dave Berman, Sue Berman, Kathy Jahn, Bruce McDonald, Bruce Pynn; kneeling: Mike Fracasso

Born This Day: Clarence Edward Dutton

Task Force X © DC Comics

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

Sunday Comics: Liberty Meadows

Today's web comic from Frank Cho

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.

Born This Day: James Flavin

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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.

Gorgo by Steve Ditko

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

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.

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.

Evolutionary Adaptations Can Be Reversed, But Rarely

Hidden Randomness between Fitness Landscapes Limits Reverse Evolution. 2011. L. Tan, et al. Phys. Rev. Lett. 106, 198102

FF © Marvel Comics

Ever since Charles Darwin proposed his theory of evolution in 1859, scientists have wondered whether evolutionary adaptations can be reversed.

Answering that question has proved difficult, partly due to conflicting evidence. In 2003, scientists showed that some species of insects have gained, lost and regained wings over millions of years. But a few years later, a different team found that a protein that helps control cells' stress responses could not evolve back to its original form.



The critical question to ask is not whether evolution is reversible, but under what circumstances it could be. "It's known that evolution can be irreversible. And we know that it's possible to reverse evolution in some cases. So what you really want to know is: What fraction of the time is evolution reversible?"

By combining a computational model with experiments on the evolution of drug resistance in bacteria, Gore and his students have, for the first time, calculated the likelihood of a particular evolutionary adaptation reversing itself.

They found that a very small percentage of evolutionary adaptations in a drug-resistance gene can be reversed, but only if the adaptations involve fewer than four discrete genetic mutations.



In the late 19th century, paleontologist Louis Dollo argued that evolution could not retrace its steps to reverse complex adaptations — a hypothesis known as Dollo's law of irreversibility. Gore says his team's results offer support for Dollo's law, but with some qualifications.

Discovered This Day: The Frozen Body of Alfred Wegner

© Marvel Comics

In 1931, the frozen body of Alfred Wegener was found by a search party in Greenland, where he had been on his fourth expedition since 1906 to study the ice cap and its climate. He was last seen alive by his colleagues on his 50th birthday, Nov. 1, 1930, as he left the Eismitte research post. He set off to return to the base camp at the coast with Greenlander Rasmus Villumsen after they brought relief supplies to the outpost.

Wegener was the German meteorologist and geophysicist who first gave a well-developed hypothesis of continental drift. Others saw the fit of coastlines of South America and Africa, but Wegener added more geologic and paleontologic evidence that these two continents were once joined. From Today In Science History

Manidens condorensis, A New Heterodontosaurid From Patagonia

A Middle Jurassic heterodontosaurid dinosaur from Patagonia and the evolution of heterodontosaurids. 2011. D. Pol, et al. Naturwissenschaften, 98:369–379.



Abstract [edit]: Heterodontosauridae is a morphologically divergent group of dinosaurs that has recently been interpreted as one of the most basal clades of Ornithischia. Heterodontosaurid remains were previously known from the Early Jurassic of southern Africa, but recent discoveries and studies have significantly increased the geographical and temporal range for this clade.

Here, we report a new ornithischian dinosaur from the Middle Jurassic Cañadón Asfalto Formation in central Patagonia, Argentina. This new taxon, Manidens condorensis gen. et sp. nov., includes well-preserved craniomandibular and postcranial remains and represents the only diagnostic ornithischian specimen yet discovered in the Jurassic of South America so far.

Derived features of its anatomy indicate that Manidens belongs to Heterodontosauridae, as the sister taxon of Heterodontosaurus and other South African heterodontosaurids. The presence of posterior dentary teeth with high crowns but lacking extensive wear facets in Manidens suggests that this form represents an intermediate stage in the development of the remarkable adaptations to herbivory described for Heterodontosaurus. At an estimated total length of 60–75 cm, Manidens furthermore confirms the small size of basal heterodontosaurids.

Cranial Osteology of a Juvenile Tarbosaurus

Cranial osteology of a juvenile specimen of Tarbosaurus bataar from the Nemegt Formation (Upper Cretaceous) of Bugin Tsav, Mongolia. Journal of Vertebrate Paleontology. 31(3). 2011. Tsuihiji, T., M. Watabe, K. Tsogtbaatar, T. Tsubamoto, R. Barsbold, S. Suzuki, A. H. Lee, R. C. Ridgely, Y. Kawahara, and L. M. Witmer.

Get the PDF from the Project Website

Courtesy of the Hayashibara Museum of Natural Sciences.

While adult tyrannosaurs wielded power and size to kill large prey, youngsters used agility to hunt smaller game.

An international team of scientists have analyzed the youngest and most-complete known skull for any species of tyrannosaur, offering a new view of the growth and feeding strategies of these fearsome predators.

"It's one of the secrets of success for tyrannosaurs—the different age groups weren't competing with each other for food because their diets shifted as they grew," said Ohio University paleontologist Lawrence Witmer.

The Tarbosaurus skull was found as part of an almost complete skeleton, missing only the neck and a portion of the tail. Estimated to have been only 2 to 3 years old when it died, was about 9 feet in total length, about 3 feet high at the hip and weighed about 70 pounds.

"The juvenile skull shows that there must have a change in dietary niches as the animals got older," Tsuihiji said. "The younger animals would have taken smaller prey that they could subdue without risking damage to their skulls, whereas the older animals and adults had progressively stronger skulls that would have allowed taking larger, more dangerous prey." link

Watch the video

Read the fact sheet

Died This Day: Skull Island Witch Doctor

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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

The Predatory Behaviour of the Thylacine

The predatory behaviour of the thylacine: Tasmanian tiger or marsupial wolf?. 2011. B. Figueirido and C. Janis. Biology Letters

Jimmy Olsen © DC Comics

Its head and body looked like a dog, yet its striped coat was cat-like. It carried its young in a pouch, like a kangaroo. No wonder the thylacine — the enigmatic, iconic creature of Australia and Tasmania — was the object of so much confusion, alternately called the "marsupial wolf" and the "Tasmanian tiger."

So what was it? By studying bones of thylacines and 31 other mammals, researchers at Brown University have the answer: The thylacine was a Tasmanian tiger — more cat than dog, although clearly a marsupial. The researchers have also shown that the extinct thylacine was a solitary, ambush-style predator. That hunting approach separates thylacines from wolves and other large canid, or dog-like, species that hunt in packs and generally pursue their quarry over some distance.

Image: Carl Buell

For millions of years, Thylacinus cynocephalus roamed mainland Australia. Its numbers declined as humans settled throughout the continent, beginning some 40,000 years ago, and the dingo, a small, dog-like creature, was introduced, about 4,000 years ago. Thylacines' last remaining outpost was in dingo-free Tasmania, but a concerted eradication effort wiped out the species. The last known thylacine, said to be named "Benjamin," died at a zoo in Hobart in 1936.

Examining the bones, they found that the thylacine's humerus was oval and elongated at the end closest to the elbow, implying that the animal's forearm bones, the radius and ulna, were separate. That means the Tasmanian tiger would have been able to rotate its arm so that the palm faced upwards, like a cat. The distal humerus on dog-like animals, such as dingoes and wolves, is "more squared-up and shorter," Janis said. This indicates the radius and ulna were closer together in these species, reflecting that these animals' hands are more fixed in the palm-down position.

In terms of hunting, the increased arm and hand movement would have given the thylacine a greater capability of subduing its quarry after a surprise attack. Since dingoes and other dog-like creatures have less latitude in arm-hand movement, that helps explain why these animals hunt by pursuit and in packs, rather than in an ambush setting, the researchers note. link

Born This Day: Thomas Huxley

From the UC Berkeley Page:

Huxley (May, 4, 1825 - June 29, 1895) was born in Ealing, near London, the seventh of eight children in a family that was none too affluent. At 21, Huxley signed on as assistant surgeon on the H.M.S. Rattlesnake, a Royal Navy frigate assigned to chart the seas around Australia and New Guinea. Huxley collected and studied marine invertebrates, in particular cnidarians, tunicates, and cephalopod mollusks. After leaving the Navy in 1854, Huxley managed to secure a lectureship at the School of Mines in London.

Huxley was a passionate defender of Darwin's theory -- so passionate that he has been called "Darwin's Bulldog" – and also a great biologist in his own right, who did original research in zoology and paleontology.

He is best known for his famous debate in June 1860, at the British Association meeting at Oxford. His opponent, Archbishop Samuel Wilberforce, was not-so-affectionately known as "Soapy Sam" for his renowned slipperiness in debate. During the debate, Archbishop Wilberforce ridiculed evolution and asked Huxley whether he was descended from an ape on his grandmother's side or his grandfather's. Accounts vary as to exactly what happened next, but according to one telling of the story, Huxley muttered "The Lord hath delivered him into my hands," and then rose to give a brilliant defense of Darwin's theory, concluding with the rejoinder, "I would rather be the offspring of two apes than be a man and afraid to face the truth."

All accounts agree that Huxley trounced Wilberforce in the debate, defending evolution as the best explanation yet advanced for species diversity.

However, Huxley did not blindly follow Darwin's theory, and critiqued it even as he was defending it. In particular, where Darwin had seen evolution and a slow, gradual, continuous process, Huxley thought that an evolving lineage might make rapid jumps, or saltations. As he wrote to Darwin just before publication of the Origin of Species, "You have loaded yourself with an unnecessary difficulty in adopting Natura non facit saltum [Nature does not make leaps] so unreservedly."



Huxley's most famous writing, published in 1863, is Evidence on Man's Place in Nature. This book, published only five years after Darwin's Origin of Species, was a comprehensive review of what was known at the time about primate and human paleontology and ethology. More than that, it was the first attempt to apply evolution explicitly to the human race. Huxley explicitly presented evidence for human evolution.

Huxley founded a remarkable dynasty of English scientists and thinkers. His son Leonard was a noted biographer and "man of letters." Leonard's oldest son Julian was one of the authors of the evolutionary synthesis of the early 20th century; Julian's son Francis became a noted anthropologist. Julian's brother Aldous Huxley was a novelist, screenwriter and essayist; his best-known book is the anti-utopia Brave New World.

Born This Day: Sir D'Arcy Thompson

From cscs.umich.edu:

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.

Surrounded By Sea Honkers!

Microspectroscopic Evidence of Cretaceous Bone Proteins. 2011. J. Lindgren et al. PLoS ONE 6(4): e19445.

Turok © current copyright holders.

Scientists have visualized type I collagen in a mosasaur fossil. Collagen previously been reported in dinosaur fossils based primarily on mass spectrometric analyses. link

Published This Day: Species Plantarum by Linnaeus

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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.

The Linnean Society

Born This Day: Pierre Teilhard de Chardin

From the San Jose University webpage:

Teilhard de Chardin (May 1, 1881 – April 10, 1955) was a paleontologist, Jesuit priest and philosopher, who was born in Auvergne, France. He lectured in science at the Jesuit College in Cairo, became professor of geology at the Intitut Catholique in Paris, and studied at the Institute of Human Paleontology at the Museum of Natural History in Paris. In 1922 he obtained his doctorate and a year later left France on a paleontological expedition to China, where he stayed until 1946.

His many writings include Building the Earth, Le Milieu Divin, Trialogues at the Edge of the West, various essays. His major work, The Phenomenon of Man (written 1938-40) was posthumously published. Based on Teilhardís scientific thinking, it argues the humanity is in a continuous process of evolution towards a perfect spiritual state.