Via flight global.
Wednesday, November 30, 2011
Thursday, November 17, 2011
Duration of the Permian Extinction
"This is the first paper to provide rates of such massive extinction," says Dr. Charles Henderson, professor in the Department of Geoscience at the University of Calgary and co-author of the paper: Calibrating the end-Permian mass extinction. "Our information narrows down the possibilities of what triggered the massive extinction and any potential kill mechanism must coincide with this time."About 95 percent of marine life and 70 percent of terrestrial life became extinct during what is known as the end-Permian, a time when continents were all one land mass called Pangea. The environment ranged from desert to lush forest. Four-limbed vertebrates were becoming diverse and among them were primitive amphibians, reptiles and a group that would, one day, include mammals.Through the analysis of various types of dating techniques on well-preserved sedimentary sections from South China to Tibet, researchers determined that the mass extinction peaked about 252.28 million years ago and lasted less than 200,000 years, with most of the extinction lasting about 20,000 years."These dates are important as it will allow us to understand the physical and biological changes that took place," says Henderson. "We do not discuss modern climate change, but obviously global warming is a biodiversity concern today. The geologic record tells us that 'change' happens all the time, and from this great extinction life did recover."
That's far and away the shortest time period that I've heard for the PT. I'd be interested in what other contrasting sources have to show.
Protoceratops Nest Full of Babies
A 70-million-year-old nest of the dinosaur Protoceratops andrewsi has been found with evidence that 15 juveniles were once inside it, according to a paper in the latestJournal of Paleontology.While large numbers of eggs have been associated with other dinosaurs, such as the meat-eating Oviraptor or certain duck-billed hadrosaurs, finding multiple juveniles in the same dino nest is quite rare.
This would be the strongest evidence yet of parental care of ceratopsians. That has been a topic of considerable arguments as of late. In fact, one of the papers in the book, Horns and Beaks, iirc, argued that ceratopsians abandoned their young to form their own pre breeding herds in NorAm. Now Protoceratops is not Triceratops by any means, but being related as closely as they (relatively) are makes it more likely that the NorAm ceratopsians gave as much parental care.
Wednesday, November 16, 2011
Three-Dimensionally Preserved Integument Reveals Hydrodynamic Adaptations in the Extinct Marine Lizard Ectenosaurus (Reptilia, Mosasauridae)
Three-Dimensionally Preserved Integument Reveals Hydrodynamic Adaptations in the Extinct Marine Lizard Ectenosaurus (Reptilia, Mosasauridae)1. Johan Lindgren (a,*)2. Michael J. Everhart (b)3. Michael W. Caldwell(c)a. Department of Earth and Ecosystem Sciences, Lund University, Lund, Swedenb. Sternberg Museum of Natural History, Fort Hays State University, Hays, Kansas, United States of Americac. Department of Earth and Atmospheric Sciences, and Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada* E-mail: johan.lindgren@geol.lu.seAbstract:The physical properties of water and the environment it presents to its inhabitants provide stringent constraints and selection pressures affecting aquatic adaptation and evolution. Mosasaurs (a group of secondarily aquatic reptiles that occupied a broad array of predatory niches in the Cretaceous marine ecosystems about 98–65 million years ago) have traditionally been considered as anguilliform locomotors capable only of generating short bursts of speed during brief ambush pursuits. Here we report on an exceptionally preserved, long-snouted mosasaur (Ectenosaurus clidastoides) from the Santonian (Upper Cretaceous) part of the Smoky Hill Chalk Member of the Niobrara Formation in western Kansas, USA, that contains phosphatized remains of the integument displaying both depth and structure. The small, ovoid neck and/or anterior trunk scales exhibit a longitudinal central keel, and are obliquely arrayed into an alternating pattern where neighboring scales overlap one another. Supportive sculpturing in the form of two parallel, longitudinal ridges on the inner scale surface and a complex system of multiple, superimposed layers of straight, cross-woven helical fiber bundles in the underlying dermis, may have served to minimize surface deformation and frictional drag during locomotion. Additional parallel fiber bundles oriented at acute angles to the long axis of the animal presumably provided stiffness in the lateral plane. These features suggest that the anterior torso of Ectenosaurus was held somewhat rigid during swimming, thereby limiting propulsive movements to the posterior body and tail.
Tuesday, November 08, 2011
Return to the XenoPermian
A Quick Intro:
The XenoPermian Period is a fictitious, alternate geological period that takes place because we hand wave away the Permian Extinction. The assumed point of departure is that the Permian Extinction never takes place. The reason for this is that the Siberian Traps are defused and their eruptions happen over a much longer period of time. This has knock-on effects. One of them being that the world's geography is different and another being that evolution has gone in rather different directions, too.
Scott, Raven, Zach and I have been working on this for some time. We'd hoped to be further along than we are, but there have been multiple setbacks and everyone has been dealing with other projects and life in general. I either had the choice of waiting until the project was further along - which would mean probably another year - or going ahead and unveiling what we have so far.
With that in mind, I have decided to start showing off what we have. I will be putting up one XenoPermian post every other week. This will space out the posts enough that maybe we might be able to get something else done prior to the last post and reduce the lag getting new artwork done.
Geography and Areas of Interest
A world is a big place. Covering the whole world is rather difficult even in a fantasy world like the XenoPermian. This is doubly difficult because we want to give a "real" sampling of the ecologies. One of the criticisms we have for Dougal Dixon is that he does such a tepid sampling that the world feels incredibly unfinished. We realized part way through we can do better, but not even get as close as we wanted to get this done right. Even then, when we considered a better than tepid attempt, but less than boiling, we realized the world was simply too big. To that end, we settled on six places to cover, with a seventh possible if we had time (ha!). The six places are Arctica, Ural Sea, Megavongo, Transpangean Mountains, Karoo and Conan Doyle's Relica.
Let's run through the five and exhibit some of the high level characteristics of each environ and the biota there.
Arctica:
Arctica is as close to a tundra as can exist under the conditions of the XenoPermian. It has very seasonal weather. This is no surprise given that the whole environment is above the Arctic Circle. While there are some shrub like vegetation, in the form of various conifers, the vast majority of the plants present are ferns. They sprout during the start of spring as the sun moves above the horizon and then die as the sunsets for winter. Life in the north polar region is tough, albeit not as tough as Arctic of our Holocene. Temperatures hover around freezing in the winter and get quite warm in the summer. Snow dusts and covers, but no more than what can happen in, say, the Midwestern states of the US in relative spring. That's nontrivial, but not what happens in the depths of winter of our Holocene. Since vegetation is sparse in winter, most herds of animals out migrate to the more southern reaches.
Animal life is dominated thoroughly by the therapsids. While archosaurs are present, the parareptiles and nonarchosaurian diapsids are largely not. The waters are filled with temnospondyls and lepospondyls, though there are no known reptilomorphs. Despite the presence of the macrofauna, the biggest presence is actually insect and a huge number of archaic invertebrate detrivores that are active even in winter munching up the dead ferns and fertilizing for the next spring.
Megavongo:
The Megavongo is a vast outletless river delta that covers a huge area in what would have been North America. This is similar to the Okavango Delta in modern Africa, but on a far, far grander scale. Life during the dry season is much like living in a desert, even one you would fine in modern Arizona or southern New Mexico, but when the megamonsoon rains hit the Transpangean Mountains, a fraction, albeit a still vast inundation, runs down the far side of the mountains and into the dry desert. The model is much like what happens in the Ethiopian Highlands for the Okavango Delta and Nile River.
Life here is harsh and dry for most of the year. Seasonal ferns mixed with specialized horsetails and lots of seed plants, especially cycads and conifers. The most inland fringes of the delta, furthest away from the seasonal water source nearly salt flats.
The fauna here is dominated by migrants. Animals conduct impressive migrations from the foothills of the Transpangaean Mountains and the coasts of the Panthalassa and Tethys consume and breed. All clades, parareptilian, diapsid & archosarian, and therapsid participate. Of those that stay between the wet seasons, active or aestivating, there is surprising diversity amongst the clades, though shockingly low on the species level.
Transpangean Mountains:
These are the mountains that straddle and divide the vast Pangaea supercontinent. Due to the fact that the world has a lower than lower oxygen level than in our time (18% instead of 21 %), the mountains make for an interesting, but rather different biota than elsewhere. The upper altitudes are filled with archosaurs and archaic amphibians in cloud forests that get megamonsoons. The lower reaches in the rift that will eventually become the Newark supergroup, is a tropical rain forest with extremely unique mix of the clades.
Karoo:
The Karoo of what is modern South Africa also joins the mix as a temperate environment. A mix of plains, forests and everything between can be found here. Despite its name, this environment stretches all the way from one side of the Therapsids dominate southern hemisphere's terrestrial environment to the other, producing a swath of life filling the analogous role of Eurasia in our own biota.
Here, too, therapsids dominate, but the neoparieasaurs and the archosaurs have truly important additions. Vast herds migrating from along the latitudes are common here. Some that reach even from one end to the other in circular migratory paths.
Conan Doyle's Relica:
Lost worlds are a common theme. The Xenopermian is an extrapolation of the lost biota of the end Permian. Here, though, too a large single island has allowed populations of archaic forms to survive...and evolve in different directions than the mainland populations. Relica separated from the mainland during the early Permian allowing for pelycosaur grade synapsids and early parareptiles to evolve into strange, but plausible forms independent of the therapsids and more derived mainland clades. What happens when a sphenodont evolves for 60 million years independently of the therapsids and differently?
Life here is harsh and very similar in flora to Arctica, at least in analogous forms. Yet still very, very unique.
Ural Sea:
We jump back to the northern hemisphere for an environment that is like someone took the Red Sea, Tropical Forests, the coast of California and coast of Crimea and mixed them up in a massive way. Flanked in the east by the AnteUral Mountains and the West by the ProtoUral Mountains, the Ural Sea formed when the two mountain ranges that would form the future Ural Mountains caused the crust between them to buckle under rather than rise. Due to the weathering from the two mountain ranges, the sea is a very fertile and the lands, although narrow in the east-west direction, are very fertile as well, sporting a terrestrial fauna as diverse and teeming as the marine.
The reason that the Ural Sea was held to last, out of the north to south order, is that this is our first land to visit and the first
The XenoPermian Pareiasaurs, the pseudochelonids and their phylogeny, are our first graphic examples of the Xenopermian. They are excellent examples of one side of a megafaunal arms race!
Check back on 11/22!
The XenoPermian Period is a fictitious, alternate geological period that takes place because we hand wave away the Permian Extinction. The assumed point of departure is that the Permian Extinction never takes place. The reason for this is that the Siberian Traps are defused and their eruptions happen over a much longer period of time. This has knock-on effects. One of them being that the world's geography is different and another being that evolution has gone in rather different directions, too.
Scott, Raven, Zach and I have been working on this for some time. We'd hoped to be further along than we are, but there have been multiple setbacks and everyone has been dealing with other projects and life in general. I either had the choice of waiting until the project was further along - which would mean probably another year - or going ahead and unveiling what we have so far.
With that in mind, I have decided to start showing off what we have. I will be putting up one XenoPermian post every other week. This will space out the posts enough that maybe we might be able to get something else done prior to the last post and reduce the lag getting new artwork done.
Geography and Areas of Interest
A world is a big place. Covering the whole world is rather difficult even in a fantasy world like the XenoPermian. This is doubly difficult because we want to give a "real" sampling of the ecologies. One of the criticisms we have for Dougal Dixon is that he does such a tepid sampling that the world feels incredibly unfinished. We realized part way through we can do better, but not even get as close as we wanted to get this done right. Even then, when we considered a better than tepid attempt, but less than boiling, we realized the world was simply too big. To that end, we settled on six places to cover, with a seventh possible if we had time (ha!). The six places are Arctica, Ural Sea, Megavongo, Transpangean Mountains, Karoo and Conan Doyle's Relica.
Let's run through the five and exhibit some of the high level characteristics of each environ and the biota there.
Arctica:
Arctica is as close to a tundra as can exist under the conditions of the XenoPermian. It has very seasonal weather. This is no surprise given that the whole environment is above the Arctic Circle. While there are some shrub like vegetation, in the form of various conifers, the vast majority of the plants present are ferns. They sprout during the start of spring as the sun moves above the horizon and then die as the sunsets for winter. Life in the north polar region is tough, albeit not as tough as Arctic of our Holocene. Temperatures hover around freezing in the winter and get quite warm in the summer. Snow dusts and covers, but no more than what can happen in, say, the Midwestern states of the US in relative spring. That's nontrivial, but not what happens in the depths of winter of our Holocene. Since vegetation is sparse in winter, most herds of animals out migrate to the more southern reaches.
Animal life is dominated thoroughly by the therapsids. While archosaurs are present, the parareptiles and nonarchosaurian diapsids are largely not. The waters are filled with temnospondyls and lepospondyls, though there are no known reptilomorphs. Despite the presence of the macrofauna, the biggest presence is actually insect and a huge number of archaic invertebrate detrivores that are active even in winter munching up the dead ferns and fertilizing for the next spring.
Megavongo:
The Megavongo is a vast outletless river delta that covers a huge area in what would have been North America. This is similar to the Okavango Delta in modern Africa, but on a far, far grander scale. Life during the dry season is much like living in a desert, even one you would fine in modern Arizona or southern New Mexico, but when the megamonsoon rains hit the Transpangean Mountains, a fraction, albeit a still vast inundation, runs down the far side of the mountains and into the dry desert. The model is much like what happens in the Ethiopian Highlands for the Okavango Delta and Nile River.
Life here is harsh and dry for most of the year. Seasonal ferns mixed with specialized horsetails and lots of seed plants, especially cycads and conifers. The most inland fringes of the delta, furthest away from the seasonal water source nearly salt flats.
The fauna here is dominated by migrants. Animals conduct impressive migrations from the foothills of the Transpangaean Mountains and the coasts of the Panthalassa and Tethys consume and breed. All clades, parareptilian, diapsid & archosarian, and therapsid participate. Of those that stay between the wet seasons, active or aestivating, there is surprising diversity amongst the clades, though shockingly low on the species level.
Transpangean Mountains:
These are the mountains that straddle and divide the vast Pangaea supercontinent. Due to the fact that the world has a lower than lower oxygen level than in our time (18% instead of 21 %), the mountains make for an interesting, but rather different biota than elsewhere. The upper altitudes are filled with archosaurs and archaic amphibians in cloud forests that get megamonsoons. The lower reaches in the rift that will eventually become the Newark supergroup, is a tropical rain forest with extremely unique mix of the clades.
Karoo:
The Karoo of what is modern South Africa also joins the mix as a temperate environment. A mix of plains, forests and everything between can be found here. Despite its name, this environment stretches all the way from one side of the Therapsids dominate southern hemisphere's terrestrial environment to the other, producing a swath of life filling the analogous role of Eurasia in our own biota.
Here, too, therapsids dominate, but the neoparieasaurs and the archosaurs have truly important additions. Vast herds migrating from along the latitudes are common here. Some that reach even from one end to the other in circular migratory paths.
Conan Doyle's Relica:
Lost worlds are a common theme. The Xenopermian is an extrapolation of the lost biota of the end Permian. Here, though, too a large single island has allowed populations of archaic forms to survive...and evolve in different directions than the mainland populations. Relica separated from the mainland during the early Permian allowing for pelycosaur grade synapsids and early parareptiles to evolve into strange, but plausible forms independent of the therapsids and more derived mainland clades. What happens when a sphenodont evolves for 60 million years independently of the therapsids and differently?
Life here is harsh and very similar in flora to Arctica, at least in analogous forms. Yet still very, very unique.
Ural Sea:
We jump back to the northern hemisphere for an environment that is like someone took the Red Sea, Tropical Forests, the coast of California and coast of Crimea and mixed them up in a massive way. Flanked in the east by the AnteUral Mountains and the West by the ProtoUral Mountains, the Ural Sea formed when the two mountain ranges that would form the future Ural Mountains caused the crust between them to buckle under rather than rise. Due to the weathering from the two mountain ranges, the sea is a very fertile and the lands, although narrow in the east-west direction, are very fertile as well, sporting a terrestrial fauna as diverse and teeming as the marine.
The reason that the Ural Sea was held to last, out of the north to south order, is that this is our first land to visit and the first
The XenoPermian Pareiasaurs, the pseudochelonids and their phylogeny, are our first graphic examples of the Xenopermian. They are excellent examples of one side of a megafaunal arms race!
Check back on 11/22!
Monday, October 10, 2011
Thursday, September 29, 2011
Tuesday, September 27, 2011
Thursday, September 22, 2011
Wednesday, September 21, 2011
Monday, September 19, 2011
This is actually pretty important...at least for us
A bit of a preface...
My family, as I have stated here before, has a very long tradition of being soldiers. My great grandfather, grandfather, father and brother all served. We served as a "family battalion" in the Civil War (Tennesseans fighting for the north). We were even exiled from Scotland for being Covenanters back in 1683 when we rose up against the then Dual Scottish/English crown (and like almost all glorious celtic rebellions rose heroically, fought like lions and were crushed thoroughly).
I've pondered that heritage more than a few times: why do we make such good soldiers? Why do we gravitate to the profession whether or not irregardless of our person wealth.
My wife and I are very different people. We often discuss it. One of the thing that came out is that I described that I truly enjoy being around other people...but I don't need to interact with others for me to be fine, even happy. My father was a true loner, but I don't see myself that way.
IDK if I ought to be very, very worried or not. I'm conflicted whether or not to take a look under the hood as another friend put it. However, the only real benefit from doing so would be to see what I can do to raise my son better. (The fringe benefit is that I get my curiosity satisfied) That alone may be worth it.
IDK when regular postings will continue. I'd like to, but...Too Damned Busy.
Tuesday, August 30, 2011
Another Terrestrial Fish
One of the world's strangest animals – a unique fish that lives on land and can leap large distances despite having no legs – has a rich and complex social life, a new study has found.The odd lifestyle of the Pacific leaping blenny (Alticus arnoldorum) has been detailed for the first time in research findings that throw new light on how animal life first evolved to colonise the land.
The Pacific leaping blenny is a marine fish yet is terrestrial in all aspects of its daily adult life, eking out a precarious existence in the intertidal zone of rocky shores in Micronesia, according to the study published in the journal Ethology , led by Dr Terry Ord, of the UNSW Evolution and Ecology Research Centre.
"This remarkable little fish seems to have made a highly successful transition across the water–land interface, although it is still needs to stay moist to enable it to breathe through its gills and skin," says Dr Ord, who is an evolutionary ecologist with a special interest in animal behaviour.
"Our study showed that life on land for a marine fish is heavily dependent on tide and temperature fluctuations, so much so that almost all activity is restricted to a brief period at mid-tide, the timing of which changes daily. During our field study on Guam we never saw one voluntary return to water. Indeed, they spend much of their time actively avoiding submersion by incoming waves, even when we tried to capture them for study.
"I can tell you they are very hard to catch and are extremely agile on land. They move quickly over complex rocky surfaces using a unique tail-twisting behaviour combined with expanded pectoral and tail fins that let them cling to almost any firm surface. To reach higher ground in a hurry, they can also twist their bodies and flick their tails to leap many times their own body length."
Working with Toni Hsieh, of Temple University in the US, Dr Ord found that adult blennies shelter in rock crevices at high and low tide, emerging at mid-tide to feed, breed and socialise in surprisingly complex ways – given their brief window of opportunity.
The researchers discovered that males are territorial and use complex visual displays to warn off rivals and attract mates. Females were seen aggressively defending feeding territory at the start of their breeding season, while males displayed a red-coloured fin and nodded their heads vigorously to attract females to their closely defended rock holes. The team filmed females inspecting these holes before entering with a chosen mate.
Little is known of their breeding and development of the young, but it seems that females lay their eggs in a chosen rock hole then play no further role in parenting, leaving the male to guard the eggs.
There's a good video here. The thing is damned agile. I was only aware of the mudskipper.
I Hate the Name Anthropocene
Anthropocene Mapping from Globaïa on Vimeo.
The Holocene is the same thing, really, and predates the goofy name. This is a nifty video though.
Nicked from James,
Wednesday, August 24, 2011
Juramaia sinensis: Earliest Known Eutherian Mammal?
A remarkably well-preserved fossil discovered in northeast China provides new information about the earliest ancestors of most of today's mammal species—the placental mammals. According to a paper published August 25 in the prestigious journal Nature, this fossil represents a new milestone in mammal evolution that was reached 35 million years earlier than previously thought, filling an important gap in the fossil record and helping to calibrate modern, DNA-based methods of dating the evolution.The paper by a team of scientists led by Carnegie Museum of Natural History paleontologist Zhe-Xi Luo describes Juramaia sinensis, a small shrew-like mammal that lived in China 160 million years ago during the Jurassic period. Juramaia is the earliest known fossil of eutherians—the group that evolved to include all placental mammals, which provide nourishment to unborn young via a placenta. As the earliest known fossil ancestral to placental mammals, Juramaia provides fossil evidence of the date when eutherian mammals diverged from other mammals: metatherians (whose descendants include marsupials such as kangaroos) and monotremes (such as the platypus). As Luo explains, "Juramaia, from 160 million years ago, is either a great-grand-aunt, or a 'great-grandmother' of all placental mammals that are thriving today."[...]The fossil of Juramaia sinensis was discovered in the Liaoning Province in northeast China and examined in Beijing by Zhe-Xi Luo and his collaborators: Chong-Xi Yuan and Qiang Ji from the Chinese Academy of Geological Sciences, and Qing-Jin Meng from the Beijing Museum of Natural History, where the fossil is stored. The name Juramaia sinensis means "Jurassic mother from China." The fossil has an incomplete skull, part of the skeleton, and, remarkably, impressions of residual soft tissues such as hair. Most importantly, Juramaia's complete teeth and forepaw bones enable paleontologists to pin-point that it is closer to living placentals on the mammalian family tree than to the pouched marsupials, such as kangaroos.
less than no time...but could not resist.
Monday, August 22, 2011
Wednesday, August 17, 2011
Wednesday, August 03, 2011
From the GLXP Summit
Thursday, July 28, 2011
Wow
This blog has been rather neglected.
I am hoping about the middle of next month, I can get past what has been eating my brain, time and life to post once more. I may get something out tomorrow though.
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