Born This Day: Raymond: Dart

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Dart (Feb. 4 1893 - Nov. 22, 1988) was an Australian-born, South African physical anthropologist. In 1924, working with students in the Taung limestone South Africa, they discovered the first Australopithecus africanus. Dubbed "missing link" at the time, skull is also known as the 'Taung child', and was only three years old at the time of death. More on Dart here

Born This Day: Gideon Mantell

Mantell (Feb. 3, 1790 – Nov. 10, 1852), a physician of Lewes in Sussex in southern England, had for years been collecting fossils in the sandstone of Tilgate forest, and he had discovered bones belonging to three extinct species: a giant crocodile, a plesiosaur, and Buckland's Megalosaurus. But in 1822 he found several teeth that "possessed characters so remarkable" that they had to have come from a fourth and distinct species of Saurian. After consulting numerous experts, Mantell finally recognized that the teeth bore an uncanny resemblance to the teeth of the living iguana, except that they were twenty times larger.
In this paper, the second published description of a dinosaur, he concluded that he had found the teeth of a giant lizard, which he named Iguanodon, or "Iguana-tooth."

Mantell illustrated his announcement with a single lithographed plate. Mantell included at the bottom of the plate a drawing of a recent iguana jaw, which is shown four times natural size, and for further comparison, he added views of the inner and outer surface of a single iguana tooth, "greatly magnified."

The traditional story that Mantell's wife found the first teeth in 1822, while the doctor was visiting a patient, appears, alas, to be unfounded.

Info and plate from HERE.

Died This Day: Ernst Mayr

Any student of biology, or anyone with an interest in the natural world, will be familiar with Ernst Mayr who passed away on February 3rd, 2005 in Bedford, Mass. Born in Kempton, Germany he joined the American Museum of Natural History as a curator in 1931. In 1953 he left the museum to work at Harvard University where he stayed until his retirement in 1975.

While working on the problem of speciation in the birds of New Guinea, Mayr realized that the multitude of species and and subspecies that he saw could best be explained as being a snapshot of evolution in action. He suggested that new species could arise when the range of one species was fractured long enough for members in different parts of the range to evolve characters that would not allow individuals to reproduce when they were brought back together again. This lead to him developing the “biological species concept” in which species are defined as populations of interbreeding organisms rather than just a collection of characters. This idea, along with his theory of “allopatric speciation” was published in his book “Systematics and the Origin of the Species” (1942) and later contributed to the “Punctuated Equilibrium” theory of Niles Eldredge and Stephen Jay Gould.

Ernst Mayr was himself inspired by the work of geneticist Theodosius Dobzhansky on the fruit fly Drosophila melanogaster and his book “Genetics and the Origin of the Species” (1937). These two men, together with the paleontologist George Gaylord Simpson, combined the sciences of genetics, zoology and paleontology into what is now known as “the new synthesis” that provides the modern experimental underpinning to the concepts that Charles Darwin presented in his book, “On the Origin of the Species” .

For anyone interested in learning more about modern evolutionary theory I’d recommend Mayr’s recent book “What Evolution Is” (2002). It’s written in an engaging and readable format from the perspective of someone who’s thought about evolution all his life.

40,000 Years of London

Published This Day (1868): Variation of Animals and Plants under Domestication by Darwin

From Today In Science History:

In 1868, Charles Darwin's book - Variation of Animals and Plants under Domestication - was published. He was 58. It is probably the second in importance of all his works. This was a follow-up work, written in response to criticisms that his theory of evolution was unsubstantiated. Darwin here supports his views via analysis of various aspects of plant and animal life, including an inventory of varieties and their physical and behavioral characteristics, and an investigation of the impact of a species' surrounding environment and the effect of both natural and forced changes in this environment.

Died This Day: Dunkenfiled Henry Scott

Painting by Mary Parrish

Scott (Nov. 28, 1854 – Jan. 29, 1934) was an English paleobotanist and leading authority of his time on the structure of fossil plants, one of those who laid the foundations of paleobotany. He conducted experiments in the Jodrell Laboratory in Kew Gardens, where he became its honorary keeper (1892-1906). In collaboration with W.C. Williamson, he wrote three papers on fossil-plant morphology (1894-95).

Scott continued writing papers after Williamson's death and in which he described many otherwise unknown fossil plants. He wrote the classic Studies in Fossil Botany, which greatly popularized the subject.
From Today In Science History

Prehistoric Rodents With Brains The Size of Primates!

Virtual endocasts of Eocene Paramys (Paramyinae): oldest endocranial record for Rodentia and early brain evolution in Euarchontoglires. 2016. Royal Society B.

If new U of T research on the brains of an ancient rodent tells us anything, it's that bigger does not necessarily mean better.

Paramys was a large rodent by modern standards - about three kilograms, roughly the size of a small cat - that lived during the mid-Eocene, some 47 to 49 million years ago.

"The brain was certainly larger than we expected considering the time period," says Bertrand. "Even more surprising is that it [the brain] was almost as large, and in some cases larger, than primitive primates of the same time period."

The key difference is that Paramys was relatively smaller than even the most primitive primates in the neocortex region, the part of the brain that deals with "higher" brain functions like sight and hearing.

"This tells us that something is going on in the neocortex of early primates that is not observable in early rodents. " says Bertrand. "The changes in the neocortex of rodents occurred later in time and with less intensity than in primates." PR

Exceptional Preservation of the Eye of an Arthropod from the Jurassic

Exceptional preservation of eye structure in arthropod visual predators from the Middle Jurassic. 2016

Image: Earth Archives

Zoologists have succeeded in discovering the internal structure of an approximately 160 million year old compound eye of Dollocaris ingens from the Middle Jurassic.

Abstract[edit]: We reconstruct with unprecedented resolution the three-dimensional structure of the huge compound eye of a 160-million-year-old thylacocephalan arthropod from the La Voulte exceptional fossil biota in SE France.

This arthropod had about 18,000 lenses on each eye, which is a record among extinct and extant arthropods and is surpassed only by modern dragonflies.

Combined information about its eyes, internal organs and gut contents obtained by X-ray microtomography lead to the conclusion that this thylacocephalan arthropod was a visual hunter probably adapted to illuminated environments, thus contradicting the hypothesis that La Voulte was a deep-water environment.

Read more about it at Earth Archives

Died This Day: Adam Sedgwick

Adam Sedgwich (March 22, 1785 - January 27, 1873) was an English geologist who first applied the name Cambrian to the geologic period of time, now dated at 570 to 505 million years ago. In 1818 he became Woodwardian Professor of Geology at Cambridge, holding a chair that had been endowed ninety years before by the natural historian John Woodward.

He lacked formal training in geology, but he quickly became an active researcher in geology and paleontology. Many years after Sedgwick's death, the geological museum at Cambridge was renamed the Sedgwick Museum of Geology in his honor. The museum is now part of the Department of Earth Sciences at Cambridge University. From Today In Science History.

Born This Day: Roy Chapman Andrews

Photo from Parade of Life Through The Ages, by Charles Knight, Nat. Geo., Feb. 1942.

From the American Museum of Natural History web site:

Adventurer, administrator, and Museum promoter — Andrews (Jan. 26, 1884 – March 11, 1960) spent his entire career at the American Museum of Natural History, where he rose through the ranks from departmental assistant, to expedition organizer, to Museum director.

He became world famous as leader of the Central Asiatic Expeditions, a series of expeditions to Mongolia that collected, among other things, dinosaur eggs. Although on these expeditions, Andrews himself found few fossils, and during his career he was not known as an influential scientist, he instead filled the role of promoter, creating immense excitement and successfully advancing the research and exhibition goals of the museum.

Learn about the Roy Chapman Andrews Society HERE.

Born This Day: Theodosius Dobzhansky

Dobzhansky (Jan.25, 1900–Dec. 18, 1975) is noted for being one of the architects of the modern Synthetic Theory of evolution. During the first 20 years of the 20th century, Darwin's theory of natural selection had fallen out of favor among scientists. Many thought it insufficient to explain the origin of adaptations, while new discoveries of gene mutations seemed to them to be incompatible with Darwinian models of change.

But in 1937 Dobzhansky published his book, Genetics and the Origin of Species, that was the first systematic overview view encompassing organic diversity, variation in natural populations, selection, isolating mechanisms (a term he coined) and species as natural units.

Later, working with Sewall Wright, he went on to demonstrate how evolution can produce stability and equilibrium in populations rather than constant directional change. link. image.

Premiered This Day (1956): The Animal World

“2 Billion Years in the Making!”

Produced and directed by Irwin Allen, whose long career included such TV hits as Lost In Space and Voyage To The Bottom Of The Sea, and movies like The Poseidon Adventure and The Towering Inferno.

The Animal World was one of the first films to present dinosaurs in the quasi-nature documentary so beloved by the Discovery Channel today. Rarely seen now, it featured about 10 minutes of great dinosaur stop-animation by Ray Harryhausen with Willis O’Brien. The entire sequence was released as an extra on the 2003 DVD release of The Black Scorpion.

Louis Agassiz, A Life In Four Pages

Read it HERE.

Eotrachodon orientalis, A New Hadrosaurid from Appalachia

A primitive hadrosaurid from southeastern North America and the origin and early evolution of 'duck-billed' dinosaurs. Journal of Vertebrate Paleontology. 2016.

This new discovery shows that duck-billed dinosaurs originated in the eastern United States, what was then broadly referred to as Appalachia, before dispersing to other parts of the world. PR

Dracoraptor hanigani, 200 Million Year Old Theropod from Wales

The Oldest Jurassic Dinosaur: A Basal Neotheropod from the Hettangian of Great Britain. PLoS ONE 11(1): e0145713.

Art by Credit Bob Nicholls

Dracoraptor hanigani from south of Wales is possibly the oldest known Jurassic dinosaur from the UK.

The 200 cm long specimen appears to be a juvenile animal, as most of its bones were not yet fully formed or fused. PR

Left premaxilla with tooth in lateral view.

Prospea holoserisca, A Burrowing Frog From the Late Paleocene of Mongolia

A burrowing frog from the late Paleocene of Mongolia uncovers a deep history of spadefoot toads (Pelobatoidea) in East Asia. 2016. Scientific Reports

Abstract [edit]: Crown-group spadefoot toads (Anura: Pelobatoidea) are the best-known fossorial frog clade to inhabit arid environments, with species utilizing a characteristic bony spade on their foot for burrowing. Here we report a rare fossil of a crown-group spadefoot toad from the late Paleocene of Mongolia.

The late Paleocene age and other information suggestive of a mild climate cast doubt on the conventional assertion that burrowing evolved as an adaptation to aridity in spadefoot toads.

Quantitative biogeographic analysis suggests that Scaphiopodidae, despite originating in North America, dispersed into East Asia via Beringia in the Early Cenozoic.

Notocolossus gonzalezparejasi, A Giant New Sauropod From Argentina

Argentina and the evolution of the sauropod hind foot. 2016. Nature.

Notocolossus gonzalezparejasi has a humerus 1.76 m (5 ft 9 in) in length, and an estimated mass of 40,000–60,000 kg. It is one of the largest dinosaurs, and indeed, one of the largest land animals, yet known to science.

One of the two known Notocolossus specimens preserves the hind foot in its entirety, providing the first complete look at this important part of the skeleton in a super-massive dinosaur. The Notocolossus hind foot shows distinctive features not found in any other sauropod that appear to constitute adaptations for supporting extremely great weight. PR

Congrats to Matt Lamanna and his colleagues on this great new paper!

Died This Day: Frank Reicher

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Frank Reicher (Dec. 2, 1875 – Jan. 19, 1965) was born in Munich,Germany and had a long career in Hollywood. He appeared in over 200 films, often playing small roles in minor films, and he directed over three dozen silent movies.

He is best know for playing Capt. Englehorn in King King (1933), and it’s quickie sequel Son of Kong from later that same year.

Mammoth Skeleton Reveals Human Hunting 45,000 Years Ago

Early human presence in the Arctic: Evidence from 45,000-year-old mammoth remains. 2016. Science

The remains of a mammoth that was hunted down about 45,000 years ago have revealed the earliest known evidence of humans in the Arctic.

Marks on the bones, found in far northern Russia, indicate the creature was stabbed and butchered. The tip of a tusk was damaged in a way that suggests human activity, perhaps to make ivory tools.

With a minimal age estimate of 45,000 years, the discovery extends the record of human presence in the Arctic by at least about 5,000 years.

Read more at: Phys Org.

A Baby Chasmosaurus from Alberta

A juvenile chasmosaurine ceratopsid (Dinosauria, Ornithischia) from the Dinosaur Park Formation, Alberta, Canada. JVP

Life reconstruction of the baby chasmosaur, by artist Michael Skrepnick.

Our baby Chasmosaurus paper is finally published - hurrah! Read the PR here