Below are the first three strips from V.T. Hamlin’s classic cartoon, “Alley Oop”, scanned from the reprint collection from Dragon Lady Press “Alley Oop” #1 (1987). The blog will return to regular postings later in the week.
Sunday, December 31, 2006
Here Comes Alley Oop!
Below are the first three strips from V.T. Hamlin’s classic cartoon, “Alley Oop”, scanned from the reprint collection from Dragon Lady Press “Alley Oop” #1 (1987). The blog will return to regular postings later in the week.
Thursday, December 28, 2006
Born This Day: Alfred Sherwood Romer
Dec. 28, 1894 – Nov. 5, 1973
”Romer was director of the Museum of Comparative Zoology at Harvard University until his retirement in 1961 and was one the singularly most influential vertebrate paleontologists of the 20th Century. His work ranged over virtually every
conceivable subject within that field, although it was the osteology and taxonomy of the therapsids and other proto-mammals which was nearest his heart.
In addition to this work, Romer was acutely interested in the origin and initial adaptive radiation of tetrapods, and his work became the basis for a theory of tetrapod origins which was canon until the description of Acanthostega gunnari by Clack & Coates in the 1990s. Romer was ahead of his time in his defense of monophyly of Dinosauria though he did feel that Theropoda was not ancestral to birds.” link from EvoWiki.org
Romer’s book, Vertebrate Paleontology (1966), was for many years THE textbook on VP and is still well worth picking up. One of Romer’s students, Bob Carroll, wrote an updated version entitled, ‘Vertebrate Paleontology and Evolution’, in 1987. image
No, I'm not back yet but I could not let this pass by.
”Romer was director of the Museum of Comparative Zoology at Harvard University until his retirement in 1961 and was one the singularly most influential vertebrate paleontologists of the 20th Century. His work ranged over virtually every
conceivable subject within that field, although it was the osteology and taxonomy of the therapsids and other proto-mammals which was nearest his heart.In addition to this work, Romer was acutely interested in the origin and initial adaptive radiation of tetrapods, and his work became the basis for a theory of tetrapod origins which was canon until the description of Acanthostega gunnari by Clack & Coates in the 1990s. Romer was ahead of his time in his defense of monophyly of Dinosauria though he did feel that Theropoda was not ancestral to birds.” link from EvoWiki.org
Romer’s book, Vertebrate Paleontology (1966), was for many years THE textbook on VP and is still well worth picking up. One of Romer’s students, Bob Carroll, wrote an updated version entitled, ‘Vertebrate Paleontology and Evolution’, in 1987. image
No, I'm not back yet but I could not let this pass by.
Monday, December 25, 2006
Happy Holidays!
My old friend Per Ahlberg send this card many years ago when he was still working in London at the Natural History Museum. So, I'm sharing it with you.
Have a safe and happy holiday. I'll be back to the blog in a week or so.
Some of the Great People I Work With
The Palaeoblog will be taking a short break to enjoy the holidays. But I'd like to wish all the cool folks I work with at the Cleveland Museum of Natural History all the best and thanks for a great year! Sorry I don't have photos of everyone...
VP volunteers Delina & Nicole. Casting Technician David Chapman supervises work in the gallaries.
Joe Klunder, Arky (from Exhibits) and Delina help move a new Dunkleosteous specimen onto display.
Joe cleans up our Haplocanthosaurus.
Ace preparator Gary Jackson collects some fossil fish material
Joe puts the finishing touches on 'Jane'.
Volunteer Steve Green preps some dino material
Volunteer Dale Z. digs into the Cleveland Shales
VP volunteers Delina & Nicole. Casting Technician David Chapman supervises work in the gallaries.
Joe Klunder, Arky (from Exhibits) and Delina help move a new Dunkleosteous specimen onto display.
Joe cleans up our Haplocanthosaurus.
Ace preparator Gary Jackson collects some fossil fish material
Joe puts the finishing touches on 'Jane'.
Volunteer Steve Green preps some dino material
Volunteer Dale Z. digs into the Cleveland Shales
Sunday, December 24, 2006
The Return of Chinggis Khaan
Last summer while I was in Mongolia we did not get much down time from the field. However, one afternoon between the two expeditions I took part in, the crew was taken to the village of Tugrug south of Ulannbaatar to witness “The Return of Chinggis Khaan After 800 Years”, part of Mongolia’s celebration the 800th anniversary of the founding of the Mongolian empire. In a grand display over 500 horsemen recreated the prossessions and battles of the Khaan armies.
I didn’t have my camera with me so all these great photos are by Philip Currie.
Happy Holidays from the Korean International Dinosaur Expedition (2006)!
Saturday, December 23, 2006
Giant Squid Captured
From National Geographic News:
Tsunemi Kubodera, a scientist with Japan's National Science Museum, caught the 7 m long animal earlier this month near the island of Chichijima, some 960 km southeast of Tokyo.
His team snared the animal using a line baited with small squid and shot video of the russet-colored giant as it was hauled to the surface. The squid, a young female, "put up quite a fight" as the team attempted to bring it aboard, Kudobera told the Associated Press, and the animal died from injuries sustained during the capture.
Giant squid, the world's largest invertebrates, are thought to reach sizes up to 18 m, but because they live at such great ocean depths they have never been studied in the wild.
Friday, December 22, 2006
Discovered This Day: Living Coelacanth
Internal anatomy of the coelacanth, Latimeria chalumnae.
From Today In Science History:
In 1938, a coelacanth, a primitive fish thought extinct, was discovered. Marjorie Courtenay-Latimer was curator of the museum in the port town of East London, northeast of Cape Town, South Africa, and always interested in seeing unusual specimens. Hendrik Goosen, captain of the trawler Nerine, called her to see his catch of the day before, made at about 70-m depth, off the Chalumna River southwest of East London. She spotted an unusual 5-ft fish in his "trash" fish pile. It was pale mauvy-blue with iridescent silver markings. She sent a sketch to Dr J.L.B. Smith, a senior lecturer in chemistry from Rhodes University in Grahamstown for identification. It was hailed as the zoological discovery of the century and equated to finding a living dinosaur!
Read this excerpt from ICHTHOS:
“December 22, 1938, Captain Goosen and the Nerine put into East London harbour with the usual catch of sharks, rays, starfish and rat-tail fish. But there was one unusual fish amongst the catch that had been caught in about 70 meters, near the mouth of the Chalumna River. Once ashore Captain Goosen left word at the Museum that there were several specimens at the ship for Miss Latimer. At first she said that she was too busy because she was hard at work cleaning and articulating the fossil reptile bones collected from Tarkastad. But as it was so near Christmas time she decided to go and wish the crew a “Happy Christmas” and took a taxi to the docks. There, attracted by a blue fin amid the pile of sharks, she found a magnificent fish. She and her assistant put it in a bag and persuaded a reluctant taxi driver to take it to the museum in the boot of the car. It measured 150 cm and weighed 57.5 kg. From its hard bony scales with sharp, prickly spines and paired fins looking rather like legs, she knew that it must be some kind of primitive fish.
Earth’s Climatic Heartbeat
The Heartbeat of the Oligocene Climate System. 2006. H. Pälike et al. Science 314: 1894 – 1898.
Analysis of the carbonate shells of these foraminifera microfossils that are between 23 million to 34 million years-old, has revealed that the Earth's climate and the formation and recession of glaciation events in the Earth's history have corresponded with variations in the earth's natural orbital patterns and carbon cycles.
The authors also show how simple models of the global carbon cycle, coupled to orbital controls of global temperature and biological activity, are able to reproduce the important changes observed after the world entered an "ice-house" state about 34 million years ago.
In the early half of the 20th century, Serbian physicist Milutin Milankovitch first proposed that cyclical variations in the Earth-Sun geometry can alter the Earth's climate and these changes can be discovered in the Earth's geological archives, which is exactly what this research team, consisting of members from the United Kingdom, the U.S. and Canada, has done.
An international team of researchers drilled down five km below Pacific Ocean sea level to uncover secrets of the Earth’s ancient climate.From the press release:
Analysis of the carbonate shells of these foraminifera microfossils that are between 23 million to 34 million years-old, has revealed that the Earth's climate and the formation and recession of glaciation events in the Earth's history have corresponded with variations in the earth's natural orbital patterns and carbon cycles.
The authors also show how simple models of the global carbon cycle, coupled to orbital controls of global temperature and biological activity, are able to reproduce the important changes observed after the world entered an "ice-house" state about 34 million years ago.
In the early half of the 20th century, Serbian physicist Milutin Milankovitch first proposed that cyclical variations in the Earth-Sun geometry can alter the Earth's climate and these changes can be discovered in the Earth's geological archives, which is exactly what this research team, consisting of members from the United Kingdom, the U.S. and Canada, has done.
Thursday, December 21, 2006
Turiasaurus & A New Sauropod Clade
A Giant European Dinosaur and a New Sauropod Clade. 2006. R. Royo-Torres et al. Science 314: 1925 – 1927.
The new sauropod, Turiasaurus riodevensis, is named for the Teruel area (Turia) and the village where dozens of sauropod bone fossils at the Barrihonda-El Humero site.
The sauropod is estimated to have weighed between 40 and 48 tons and is comparable to the world's largest known dinosaurs, including Argentinosaurus and Brachiosaurus. At its estimated length of 30 to 37 meters the sauropod would be as long as an NBA basketball court.
Artist rendering of Turiasaurus. AAAS/Science & Carin L. Cain
Fossils of a giant sauropod found in Teruel, Spain may have been the most massive terrestrial animal in Europe.From the press release:
The new sauropod, Turiasaurus riodevensis, is named for the Teruel area (Turia) and the village where dozens of sauropod bone fossils at the Barrihonda-El Humero site.
The sauropod is estimated to have weighed between 40 and 48 tons and is comparable to the world's largest known dinosaurs, including Argentinosaurus and Brachiosaurus. At its estimated length of 30 to 37 meters the sauropod would be as long as an NBA basketball court.
Skeletal elements of Turiasaurus riodevensis Credit: © Science
The characteristics of the new dinosaur allows the authors to group several sauropod remains from Portugal, France, United Kingdom and other Spanish areas in a new clade of dinosaurs that has more primitive limb and bone structures than other giant sauropods that have been found on other continents in Upper Jurassic to Lower Cretaceous rocks. "This dinosaur is also more evolutionary primitive than other giant sauropods found," Hanson said. 
Barrihonda-El Humero, Riodeva, Teruel, Spain Excavation. Credit: Fundación Dinópolis
Oldest Animal Fossils May Have Been Bacteria
Evidence of giant sulphur bacteria in Neoproterozoic phosphorites. 2006. J. V. Bailey et al. Nature advance online publication 20 Dec.
This week, a study in the same prestigious journal presents evidence for reinterpreting the 600 million-year-old fossils from the Precambrian era as giant bacteria.
The discovery "complicates our understanding of microfossils thought to be the oldest animals," said lead author Jake Bailey.
Bailey made his discovery by combining two separate findings about Thiomargarita, the world's largest known living bacterium. In 2005, Thiomargarita discoverer Heide Schulz showed that the bacterium promotes deposition of phosphorite. As it turs out, the fossils identified as eggs and embryos in 1998 came from southern China's Doushantuo Formation, which is rich in phosphorite.
Also in 2005, University of Georgia marine biologists found that Thiomargarita can multiply by reductive cell division, a process rare among bacteria but typical of animal embryos. The fossils had been identified as embryos in part because they showed evidence of reductive cell division.
"When I put those two pieces together, I said … perhaps they're not animal embryos at all."
The oldest-known animal eggs and embryos, whose first pictures made the cover of Nature in 1998, were so small they looked like bugs – which, it now appears, they may have been.From the press release:
This week, a study in the same prestigious journal presents evidence for reinterpreting the 600 million-year-old fossils from the Precambrian era as giant bacteria.
The discovery "complicates our understanding of microfossils thought to be the oldest animals," said lead author Jake Bailey.
Bailey made his discovery by combining two separate findings about Thiomargarita, the world's largest known living bacterium. In 2005, Thiomargarita discoverer Heide Schulz showed that the bacterium promotes deposition of phosphorite. As it turs out, the fossils identified as eggs and embryos in 1998 came from southern China's Doushantuo Formation, which is rich in phosphorite.
Also in 2005, University of Georgia marine biologists found that Thiomargarita can multiply by reductive cell division, a process rare among bacteria but typical of animal embryos. The fossils had been identified as embryos in part because they showed evidence of reductive cell division.
"When I put those two pieces together, I said … perhaps they're not animal embryos at all."
Wednesday, December 20, 2006
Sauropods: No Gastic Mills
No gastric mill in sauropod dinosaurs: new evidence from analysis of gastrolith mass and function in ostriches. 2006. O. Wings and P. M. Sander. Proceedings of the Royal Society B: Biological Sciences, early on-line publication.
Giant dinosaurs had a problem. Many of them had narrow, pointed teeth, which were more suited to tearing off plants rather than chewing them. But how did they then grind their food? Until recently many researchers have assumed that they were helped by stones which they swallowed. In their muscular stomach these then acted as a kind of 'gastric mill'.
But this assumption does not seem to be correct, as scientists have now shown that some dinosaurs did not have gastric mills such as some living birds have.
For their investigations, the scientists therefore offered stones such as limestone, rose quartz and granite as food to ostriches on a German ostrich farm. After the ostriches had been slaughtered, the scientists investigated the gastric stones. It became clear that they wore out quickly in the muscular stomach and were not polished. On the contrary, the surface of the stones, which had been partly smooth, became rough in the stomachs during the experiments.
'Whereas occasionally stones were found together with sauropod skeletons, we don't think they are remains of a gastric mill such as occurs in birds,' Dr. Sander comments. In that kind of gastric mill the stones would have been very worn and would not have a smoothly polished surface. Apart from that, gastric stones are not discovered regularly at sauropod sites. When present, their mass is, in relation to the body size, much less than with birds.
Yet what else were the dinosaurs' gastric stones used for? The researchers presume that they were accidentally eaten with their food or could have been swallowed on purpose to improve the intake of minerals.
There is another group of dinosaurs, however, whose remains of gastric stones can be linked up with a birdlike gastric mill. From these theropods today's birds developed. The gastric mill could therefore have developed in the ancestral line of birds.
Sauropods did not have a 'gastric mill.' How they processed their food without molars remains unclear.From the press release:
Giant dinosaurs had a problem. Many of them had narrow, pointed teeth, which were more suited to tearing off plants rather than chewing them. But how did they then grind their food? Until recently many researchers have assumed that they were helped by stones which they swallowed. In their muscular stomach these then acted as a kind of 'gastric mill'.
But this assumption does not seem to be correct, as scientists have now shown that some dinosaurs did not have gastric mills such as some living birds have.For their investigations, the scientists therefore offered stones such as limestone, rose quartz and granite as food to ostriches on a German ostrich farm. After the ostriches had been slaughtered, the scientists investigated the gastric stones. It became clear that they wore out quickly in the muscular stomach and were not polished. On the contrary, the surface of the stones, which had been partly smooth, became rough in the stomachs during the experiments.
'Whereas occasionally stones were found together with sauropod skeletons, we don't think they are remains of a gastric mill such as occurs in birds,' Dr. Sander comments. In that kind of gastric mill the stones would have been very worn and would not have a smoothly polished surface. Apart from that, gastric stones are not discovered regularly at sauropod sites. When present, their mass is, in relation to the body size, much less than with birds.
Yet what else were the dinosaurs' gastric stones used for? The researchers presume that they were accidentally eaten with their food or could have been swallowed on purpose to improve the intake of minerals.
There is another group of dinosaurs, however, whose remains of gastric stones can be linked up with a birdlike gastric mill. From these theropods today's birds developed. The gastric mill could therefore have developed in the ancestral line of birds.
Tuesday, December 19, 2006
Dr. Pat Druckenmiller: Extreme Paleontologist!
"We ate and ate and ate. I ate the fattiest sausage I could find. I ate nothing but fat."From Billingsgate.com:
The hunt for ancient sea monsters sometimes calls for extreme paleontologists. One, Pat Druckenmiller, flew 800 miles away from the North Pole, rode a boat across an icy fjord and jumped into the sea to reach the shore where no one lives except polar bears and reindeer.
Student Linn Kristin Novis, left, and Pat Druckenmiller discuss sausages during an expedition to the Arctic. Photo courtesy of Natural History Museum, U. Oslo
Then the Montana State University scientist hiked, rifle in hand, across an Arctic island to map the remains of 28 sea reptiles that are 150 million years old. The biggest sea reptile found - a predator nicknamed "The Monster" - had a skull as long as seven feet and a body as long as 40.
After pitching his tent in the tundra, Druckenmiller helped set up a trip-wire system to scare away polar bears from camp. Then he ate fat - lots of fat- to keep warm.
"We ate and ate and ate. I ate the fattiest sausage I could find. I ate nothing but fat," said Druckenmiller, who traveled to the Arctic last summer with a team of Norwegian-led scientists.
"The site we have chosen for next year's excavation is on a hillside with several exposures of shale," Dr. Jorn Hurum, co-leader of the team, wrote in an e-mail from the University of Oslo in Norway. "There will be three digs going on at the same time within five to 10 minutes' walking distance."
Born This Day (1944): Richard Leakey
image.
From Today In Science History:
Leakey is a Kenyan physical anthropologist, paleontologist and second of three sons of noted anthropologists Louis Leakey and Mary Leakey. At an early age, he decided he wanted nothing to do with paleoanthropology and started a expedition business. In 1964, he led an expedition to a fossil site which sparked his interest in paleontology. Since then he has been responsible for extensive fossil finds of human ancestral forms in East Africa, including a Homo habilis skull found in 1972, and a Homo erectus skull found in 1975.
His discoveries showed that man's ancestors used tools, which shows intelligence, and lived in eastern Africa at least 3 million years ago - almost doubling the previously accepted age of human origins.
Learn more about The Leakey Foundation HERE.
Monday, December 18, 2006
Evolution of Flight
A critical ligamentous mechanism in the evolution of avian flight. 2006. D.B. Baier, S.M. Gatesy and F. A. Jenkins. Nature, published online 17 Dec.
To better understand how the birds stabilized their wings during flight, they used CAT scans to make a 3D “virtual pigeon skeleton” and calculated the forces needed to maintain a gliding posture. They found that neither the shoulder socket nor the muscles could keep pigeon wings stable.
The critical player, they found, is the acrocoracohumeral ligament, a short band of tissue that connects the humerus to the shoulder joint. The ligament balances all of the forces exerted on the shoulder joint – from the pull of the massive pectoralis muscle in the bird’s breast to the push of wind under its wings – making it a linchpin for modern bird flight.
To find out if this ligament played the same shoulder-stabilizing role in primitive animals, the team looked to the alligator. In the laboratory the scientists put three alligators on motorized treadmills and took X-ray video. Baier and Stephen Gatesy found that alligators use muscles – not ligaments – to do the hard work of supporting the shoulder.
In examining the fossil record (i.e. Archaeopteryx, Confuciusornis, Sinornithoides, & Sinornithosaurus) they found that the new ligament-based force balance system appears to have evolved more gradually within Mesozoic fliers.
“What this means is that there were refinements over time in the flight apparatus of birds,” Baier said. “Our work also suggests that when early birds flew, they balanced their shoulders differently than birds do today. And so they could have flown differently."
Brown and Harvard scientists have learned that a single ligament at the shoulder joint stabilizes the wings of birds during flight.From the press release:
To better understand how the birds stabilized their wings during flight, they used CAT scans to make a 3D “virtual pigeon skeleton” and calculated the forces needed to maintain a gliding posture. They found that neither the shoulder socket nor the muscles could keep pigeon wings stable.
The critical player, they found, is the acrocoracohumeral ligament, a short band of tissue that connects the humerus to the shoulder joint. The ligament balances all of the forces exerted on the shoulder joint – from the pull of the massive pectoralis muscle in the bird’s breast to the push of wind under its wings – making it a linchpin for modern bird flight.
To find out if this ligament played the same shoulder-stabilizing role in primitive animals, the team looked to the alligator. In the laboratory the scientists put three alligators on motorized treadmills and took X-ray video. Baier and Stephen Gatesy found that alligators use muscles – not ligaments – to do the hard work of supporting the shoulder.
In examining the fossil record (i.e. Archaeopteryx, Confuciusornis, Sinornithoides, & Sinornithosaurus) they found that the new ligament-based force balance system appears to have evolved more gradually within Mesozoic fliers.
“What this means is that there were refinements over time in the flight apparatus of birds,” Baier said. “Our work also suggests that when early birds flew, they balanced their shoulders differently than birds do today. And so they could have flown differently."
Sunday, December 17, 2006
Science & Life: Hominid Evolution
I recently picked up this issue of the French science magazine, 'Science & Vie'. Cover dated June 2006, it's a special issue on the evolution of man complete with a lot of coverage on recent findings and dozens of photos and illustrations that will be useful in teaching evolution. If you live in a large enough city there should be a specialty newsstand where you can still pick this up.
CLICK IMAGES TO ENLARGE
Saturday, December 16, 2006
Drawing Dinosaurs
From Dan Varner comes a recommendation for the new instructional video, “Drawing Dinosaurs: Anatomy and Sketching” by David Krentz. From the site:
"In this DVD, David conveys a strong understanding of dinosaur anatomy mixed with the sheer joy of giving life, personality and motion to these inspiring creatures. He covers a wide range of topics from skeletal structures and muscles, to range of motion and the essential gestures of various body types. David focuses on capturing these elements in the form of quick sketches of both herbivorous and carnivorous dinosaurs."Krentz was Lead Character Designer on Disney’s ‘Dinosaur’, and has worked on numerous other films.
Check out the dvd HERE.
Friday, December 15, 2006
Phyloinformatics Hackathon
Two dozen leading bioinformatics and phylogenetics software developers are meeting at the National Evolutionary Synthesis Center in a unique hands-on exercise that will produce new open-source software for phylogenetic analysis.From the press release:
Phylogenetics is the study of the evolutionary relationships between organisms and their genes. The field is fundamental to many areas of basic biological research, and has applications from tracking the progress of disease epidemics to figuring out how best to conserve endangered populations. Techniques from phylogenetics even have been used to study the relationships among human languages and among medieval manuscripts.
Researchers rely on a bewildering array of phylogenetic methods for various specialized tasks. Solving complex problems often relies putting these individual methods together in complex ways. "The flowchart can get very complicated very fast", says Amy Zanne, a postdoctoral researcher at
NESCent whose research combines morphological, physiological and ecological data with phylogenetic methods. "Glue software is needed to make these tools speak the same language".Leading programmers from as far away as Japan and New Zealand have come to NESCent to build the missing pieces of glue software. Participants include developers of specific phylogenetic software packages, on the one hand, and experts in designing glue software toolkits such as BioPerl and BioJava.
The software produced will be freely available under an open-source license, and it is being documented as it is being produced. The first Phyloinformatics Hackathon is taking at place at NESCent in Durham, NC from December 11-15, 2006.
Thursday, December 14, 2006
Volaticotherium: Mesozoic Gliding Mammal
Abstract [edit]: Direct evidence of gliding is rare in fossil records and is unknown in mammals from the Mesozoic era. Here we report a new Mesozoic mammal [Volaticotherium antiquus—"ancient gliding beast"] —from Inner Mongolia, China, that represents a previously unknown group characterized by a highly specialized insectivorous dentition and a sizable patagium (flying membrane) for gliding flight.
The patagium is covered with dense hair and supported by an elongated tail and limbs; the latter also bear many features adapted for arboreal life. This discovery extends the earliest record of gliding flight for mammals to at least 70 million years earlier in geological history, and demonstrates that early mammals were diverse in their locomotor strategies and lifestyles; they had experimented with an aerial habit at about the same time as, if not earlier than, when birds endeavoured to exploit the sky.
Triassic Microbes In Amber
A microworld in Triassic amber. 2006. A.R. Schmidt et al. Nature: 444: 835.
Abstract: Amber provides an effective medium for conservation of soft-bodied microorganisms, but finds older than 135 million years are very rare and have not so far contained any microbial inclusions. Here we describe 220-million-year-old droplets of amber containing bacteria, fungi, algae and protozoans that are assignable to extant genera. These inclusions provide insight into the evolution and palaeoecology of Lower Mesozoic microorganisms: it seems that the basal levels of food webs of terrestrial communities (biocoenoses) have undergone little or no morphological change from the Triassic to the Recent.
More info from National Geographic News.
Abstract: Amber provides an effective medium for conservation of soft-bodied microorganisms, but finds older than 135 million years are very rare and have not so far contained any microbial inclusions. Here we describe 220-million-year-old droplets of amber containing bacteria, fungi, algae and protozoans that are assignable to extant genera. These inclusions provide insight into the evolution and palaeoecology of Lower Mesozoic microorganisms: it seems that the basal levels of food webs of terrestrial communities (biocoenoses) have undergone little or no morphological change from the Triassic to the Recent.
More info from National Geographic News.
Wednesday, December 13, 2006
New Miocene Mammal From New Zealand
Miocene mammal reveals a Mesozoic ghost lineage on insular New Zealand, southwest Pacific. 2006. T. H. Worthy et al. PNAC, published on-line.
The tiny fossilised jaw (left) and hip (below) bones that belonged to a unique, mouse-sized land animal unlike any other mammal known were unearthed from the rich St Bathans fossil bed, in the Otago region of South Island, NW.
But the real shock to scientists was that it was there at all: until now, decades of searching had shown no hint that the furry, warm-blooded animals that thrived and prospered so widely in other lands had ever trodden on New Zealand soil.
The fact that even one land mammal
had lived there, at least 16 million years ago, has put paid to the theory that New Zealand's rich bird fauna had evolved there because they had no competition from land mammals.
"It also suggests that New Zealand was not completely submerged, as some scientists thought, when sea levels were high about 25 to 30 million years ago."
The St Bathans fossil field - which has also produced many other species of animals, including fish and birds - also promises to shed new light on climate change in the Australasian region, recording a massive shift from a warm, wet phase to a much cooler and drier period.
Small but remarkable fossils found in New Zealand show for the first time that the so-called "land of birds" was once home to mammals as well.From the press release:
The tiny fossilised jaw (left) and hip (below) bones that belonged to a unique, mouse-sized land animal unlike any other mammal known were unearthed from the rich St Bathans fossil bed, in the Otago region of South Island, NW.But the real shock to scientists was that it was there at all: until now, decades of searching had shown no hint that the furry, warm-blooded animals that thrived and prospered so widely in other lands had ever trodden on New Zealand soil.
The fact that even one land mammal
had lived there, at least 16 million years ago, has put paid to the theory that New Zealand's rich bird fauna had evolved there because they had no competition from land mammals."It also suggests that New Zealand was not completely submerged, as some scientists thought, when sea levels were high about 25 to 30 million years ago."
The St Bathans fossil field - which has also produced many other species of animals, including fish and birds - also promises to shed new light on climate change in the Australasian region, recording a massive shift from a warm, wet phase to a much cooler and drier period.
Tuesday, December 12, 2006
Born This Day: Erasmus Darwin
Dec. 12, 1731 – April 18, 1802.
Erasmus was a prominent English physician, poet, philosopher, botanist, naturalist and the grandfather of naturalist Charles Darwin and the biologist Francis Galton. Erasmus Darwin was one of the leading intellectuals of 18th century England.
As a naturalist, he formulated one of the first formal theories on evolution in Zoonomia, or, The Laws of Organic Life (1794-1796). Although he did not come up with natural selection, he did discuss ideas that his grandson elaborated on sixty years later, such as how life evolved from a single common ancestor, forming "one living filament".
Download Zoonomia HERE
Erasmus was a prominent English physician, poet, philosopher, botanist, naturalist and the grandfather of naturalist Charles Darwin and the biologist Francis Galton. Erasmus Darwin was one of the leading intellectuals of 18th century England.
As a naturalist, he formulated one of the first formal theories on evolution in Zoonomia, or, The Laws of Organic Life (1794-1796). Although he did not come up with natural selection, he did discuss ideas that his grandson elaborated on sixty years later, such as how life evolved from a single common ancestor, forming "one living filament".
Download Zoonomia HERE
New Antarctic Elasmosaurid
The 70 million year old fossil remains of a 1.5m long juvenile elasmosaur represent one of the most-complete skeletons ever recovered from Antarctica.From the press release:
The animal's stomach area was spectacularly preserved. Stomach ribs (gastralia) span the abdomen, and rather than being long, straight bones like those of most plesiosaurs, these are forked, sometimes into three prongs. Moreover, numerous small, rounded stomach stones (gastroliths) are concentrated within the abdominal cavity, indicating stomach stones were ingested even by juvenile plesiosaurs to help maintain buoyancy or to aid digestion.
The skeleton is nearly perfectly articulated as it would have been in life, but the skull has eroded away from
the body. Extreme weather at the excavation site on Vega Island off the Antarctic Peninsula and lack of field time prevented further exploration for the eroded skull.The researchers speculate volcanism may have caused the animal's death. Excavation turned up volcanic ash beds layered within the shallow marine sands at the site, and chunks of ash were found with plant material inside. Silica released from the ash allowed spectacular preservation of the skeleton.
The juvenile plesiosaur appears to be related to one discovered in New Zealand in 1874. That plesiosaur was named Mauisaurus and is characterized by a rounded end of the major paddle bone. It was confined to the southern oceans where it existed more than 5 million years.
The bones will be unveiled at the South Dakota School of Mines and Technology's Museum of Geology Dec.13, 2006. image
Sunday, December 10, 2006
Sinclair Dinoland 1964-65: Part 2
As promised, here are the rest of the Dinoland booklet images. Art by Matthew Kalmenoff (thanks DV!).
Part 1 is HERE.
But wait--where's the time chart from the booklet? I'm saving that for a future posting.
Part 1 is HERE.
But wait--where's the time chart from the booklet? I'm saving that for a future posting.
Late Cretaceous Antarctic Land Bridge
Vicariant Origin of Malagasy Reptiles Supports Late Cretaceous Antarctic Land Bridge. 2006. B. P. Noonan and P.T. Chippindale. American Naturalist 168: 730-741.
ABSTRACT [edit]: Since the acceptance of Wegener's theory of plate tectonics in the 1960s, continental drift vicariance has been proposed as an explanation for pan-Gondwanan faunal distributions. Given the recognition of historical connections among continents, it no longer was necessary to invoke hypotheses of dispersal across nearly insurmountable barriers. Recent studies have demonstrated a significant, if not dominant, role for dispersal in the present-day distributions of "Gondwanan" taxa.
The evolutionary histories of three Malagasy groups (boid snakes, podocnemid turtles, and iguanid lizards) commonly have been interpreted as reflecting vicariance because of continental drift associated with the breakup of Gondwana. Bayesian analyses of divergence ages suggest that this pattern is the result of vicariance coincident with the isolation of Madagascar in the Late Cretaceous ( 80 million years ago).
This represents the first temporal evidence linking the vicariant origin of extant Malagasy vertebrates to a single geologic event. Specifically, our data provide strong, independently corroborated evidence for a contiguous Late Cretaceous Gondwana, exclusive of Africa and connected via Antarctica.
ABSTRACT [edit]: Since the acceptance of Wegener's theory of plate tectonics in the 1960s, continental drift vicariance has been proposed as an explanation for pan-Gondwanan faunal distributions. Given the recognition of historical connections among continents, it no longer was necessary to invoke hypotheses of dispersal across nearly insurmountable barriers. Recent studies have demonstrated a significant, if not dominant, role for dispersal in the present-day distributions of "Gondwanan" taxa.
The evolutionary histories of three Malagasy groups (boid snakes, podocnemid turtles, and iguanid lizards) commonly have been interpreted as reflecting vicariance because of continental drift associated with the breakup of Gondwana. Bayesian analyses of divergence ages suggest that this pattern is the result of vicariance coincident with the isolation of Madagascar in the Late Cretaceous ( 80 million years ago).
This represents the first temporal evidence linking the vicariant origin of extant Malagasy vertebrates to a single geologic event. Specifically, our data provide strong, independently corroborated evidence for a contiguous Late Cretaceous Gondwana, exclusive of Africa and connected via Antarctica.
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