The Ottawa, ON, based band <><>>>>> (aka The Band Whose Name is A Symbol, aka TBWNIS) will shortly be releasing their new vinyl-only LP, Scrappy Little Jaw. Yes, that scrappy little jaw on the cover is the holotype of Gryphoceratops.
If you want to pick up a copy of this limited edition beauty contact John at Birdman Sound.
Tuesday, February 26, 2013
Monday, February 25, 2013
The Brainless Origin of The Head
The bilaterian head patterning gene six3/6 controls aboral domain development in a cnidarian. 2013. Sinigaglia, C., et al. PLoS Biology 10.1371/journal.pbio.1001488.
In a simple, brainless sea anemone, the same genes that control head development in higher animals regulate the development of the front end of the swimming larvae. link
Author Summary [edit]: The evolutionary origin of head development is a fundamental question for understanding the evolution of animal body plans. Bilaterally symmetrical animals (Bilaterians) have an anterior-posterior (head-to-tail) axis, whose anterior end is usually characterized by a head and a brain.
Bilaterians evolved from an ancestor shared with cnidarians (corals, sea anemones, jellyfish), but brain-like structures are absent in cnidarians, although they have an obvious oral-aboral axis. Cnidarian larvae move with the aboral pole forward, but as adult polyps this pole is anchored to the ground, while the oral end is used for feeding. It is unclear whether one of the termini of cnidarians corresponds to the bilaterian head-forming region.
We show here that in the sea anemone Nematostella vectensis genes regulating bilaterian head development are expressed at the larval aboral pole and that a key anterior developmental gene, six3/6, controls the development of the aboral pole. These findings support the hypothesis that the anterior, head-forming, region of bilaterians and the aboral region of cnidarians derived from the same domain of their last common ancestor and are therefore homologues.
In a simple, brainless sea anemone, the same genes that control head development in higher animals regulate the development of the front end of the swimming larvae. link
Author Summary [edit]: The evolutionary origin of head development is a fundamental question for understanding the evolution of animal body plans. Bilaterally symmetrical animals (Bilaterians) have an anterior-posterior (head-to-tail) axis, whose anterior end is usually characterized by a head and a brain.
Bilaterians evolved from an ancestor shared with cnidarians (corals, sea anemones, jellyfish), but brain-like structures are absent in cnidarians, although they have an obvious oral-aboral axis. Cnidarian larvae move with the aboral pole forward, but as adult polyps this pole is anchored to the ground, while the oral end is used for feeding. It is unclear whether one of the termini of cnidarians corresponds to the bilaterian head-forming region.
We show here that in the sea anemone Nematostella vectensis genes regulating bilaterian head development are expressed at the larval aboral pole and that a key anterior developmental gene, six3/6, controls the development of the aboral pole. These findings support the hypothesis that the anterior, head-forming, region of bilaterians and the aboral region of cnidarians derived from the same domain of their last common ancestor and are therefore homologues.
Thursday, February 21, 2013
Bads News on Jobs for Recent Ph.D.s
Read the article at The Atlantic: The Ph.D Bust: America's Awful Market for Young Scientists—in 7 Charts
Tuesday, February 12, 2013
Born This Day: Barnum Brown
From the AMNH bio:
The greatest dinosaur hunter of the twentieth century was Barnum Brown, who began his career at the American Museum of Natural History in 1897 as an assistant to Henry Fairfield Osborn. Brown traveled all over the world collecting dinosaurs and fossil mammals. Some consider him to be the last of the great dinosaur hunters.
Brown was always impeccably dressed, often wearing a tie and topcoat even in the field. He was a shrewd "horse trader" when it came to wheeling and dealing for fossil specimens. Many of Brown's greatest discoveries, including the first specimens of Tyrannosaurus rex ever found, are displayed in the Museum's Dinosaur Halls.
The greatest dinosaur hunter of the twentieth century was Barnum Brown, who began his career at the American Museum of Natural History in 1897 as an assistant to Henry Fairfield Osborn. Brown traveled all over the world collecting dinosaurs and fossil mammals. Some consider him to be the last of the great dinosaur hunters.
Brown was always impeccably dressed, often wearing a tie and topcoat even in the field. He was a shrewd "horse trader" when it came to wheeling and dealing for fossil specimens. Many of Brown's greatest discoveries, including the first specimens of Tyrannosaurus rex ever found, are displayed in the Museum's Dinosaur Halls.
Sunday, February 10, 2013
Published This Day: Steno Recognizes the Organic Origin of Fossils
From Today In Science History:
In 1667, a classic paleontological paper by Nicolaus Steno was published by the Royal Society, London. His topic, Head of a shark dissected, represented the first such scientific paper to recognise that fossils were the remains of creatures who had died and subsequently had become petrified. Controversy resulted as the same claim had been made in the time of the ancient Greeks, two millennia earlier.
In 1667, a classic paleontological paper by Nicolaus Steno was published by the Royal Society, London. His topic, Head of a shark dissected, represented the first such scientific paper to recognise that fossils were the remains of creatures who had died and subsequently had become petrified. Controversy resulted as the same claim had been made in the time of the ancient Greeks, two millennia earlier.
Saturday, February 09, 2013
Asteroid Did Kill The Dinosaurs
Time Scales of Critical Events Around the Cretaceous-Paleogene Boundary. 2013. P.R. Renne, et al. Science 339: 684-687.
Abstract: Mass extinctions manifest in Earth's geologic record were turning points in biotic evolution. We present 40Ar/39Ar data that establish synchrony between the Cretaceous-Paleogene boundary and associated mass extinctions with the Chicxulub bolide impact to within 32,000 years. Perturbation of the atmospheric carbon cycle at the boundary likely lasted less than 5000 years, exhibiting a recovery time scale two to three orders of magnitude shorter than that of the major ocean basins. Low-diversity mammalian fauna in the western Williston Basin persisted for as little as 20,000 years after the impact. The Chicxulub impact likely triggered a state shift of ecosystems already under near-critical stress.
Abstract: Mass extinctions manifest in Earth's geologic record were turning points in biotic evolution. We present 40Ar/39Ar data that establish synchrony between the Cretaceous-Paleogene boundary and associated mass extinctions with the Chicxulub bolide impact to within 32,000 years. Perturbation of the atmospheric carbon cycle at the boundary likely lasted less than 5000 years, exhibiting a recovery time scale two to three orders of magnitude shorter than that of the major ocean basins. Low-diversity mammalian fauna in the western Williston Basin persisted for as little as 20,000 years after the impact. The Chicxulub impact likely triggered a state shift of ecosystems already under near-critical stress.
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