serpentface · 4 months ago
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What exactly are living gods in the blightseed universe?
Ok here's the (DANGEROUSLY vestigial at this point) Meta Deeplore:
There is a material form of energy that is utilized by biological bodies essentially as an animating force. This IS the vaguely defined, extremely ambiguous magic in the setting. It is what produces the actual experience of Consciousness and can be basically considered 1:1 with conscious experience. All life utilizes this energy (whether actually conscious life in the traditional sense or not).
It cannot be created or destroyed, and rather follows pathways of dispersal between one material plane and a parallel plane. This parallel plane is 'the ether' 'the dreamlands' etc, and has its own matter. Discrete entities from the dreamlands are essentially formed as a byproduct of consciousness and, when interacted with, are deeply susceptible to the influence of conscious Thought (they are essentially matter organized By consciousness and can be reorganized by consciousness)
These are the entities that can become living gods. Dreamlands fauna occasionally slips into prime material reality, at which point they are directly under the influence of consciousness and can be transformed. Dreamlands fauna in of itself is not directly perceivable but produces a sense of Presence, like the feeling of being watched when alone in the wilderness, a 'third man effect', a sense of inexplicable awe or fear, seeing shadows from the corner of your eye, etc. The combination of their tangible effects and their susceptibility to consciousness creates a self-reinforcing cycle that produces living gods.
IE: if one is on a forest and people experience the sensation of its presence, belief that there is some entity there may develop. This will follow the lines of the cultural worldview- say there are already beliefs in spectral hounds that encounter travelers at night, it might be interpreted as a location-specific hound, given a name and identity through stories. This in turn causes the dreamlands fauna to physically embody that form and the assumed qualities, and people will start having absolute materially real encounters with it, thus reinforcing the initial beliefs that created it and generating new elements of the mythology. This is what a living god is.
They need persistent, localized, and coherent beliefs to hold their forms. If a village creates a living god and is then wiped out in a disaster, the god will gradually lose its form and return to its initial state of a sense of Presence. This is also a limiting factor on the 'size' and power of a living god, if an entire religion formed around it and became a widespread phenomena, the living god itself cannot 'keep up'. It is sustained on direct and localized interactions, so belief becoming widely dispersed (especially if the localized belief is lost) will cause it to gradually become less discrete. The effect of this property is that living gods are almost always minor deities or spirits tied to a specific location by a specific nearby culture. A lot of deities in larger religions may have once had a living god component that is now indiscrete.
The living god of the Ur-tree is an unusual exception in that it was created over millennia, basically by the survival instincts of the Plants it interacts with, and has held its form over hundreds of millions of years due to this being ubiquitous and un-susceptible to cultural change. The only thing that could 'kill it' is if its forest was entirely destroyed.
So 99% of living gods can be described as thoughtforms created by the process of folkloric/religious development. They are created BY people and not the other way around, and nothing about their nature confirms or denies the existence of other deities or etc.
And yeah I'm going to be 100% real I am REALLY tempted to dump even this extremely ambiguous magical element like it is soooooooooooooooo fucking NOT important to the setting at this point. I've kind of allowed 'literal god entities created by mortal belief' to be just a tiny part of the world's fabric by their nature, like it works within the worldbuilding for such a hugely significant concept to ultimately be insignificant in the overall framework, so I COULD just Leave It but idk. If it were not for me wanting to still have my big fucking god tree and a talking dog as an actual character it would be out of here soooo fast..........
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bunjywunjy · 4 years ago
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Why were animals so giant in prehistoric times?
at least some animals in any given ecosystem tend to evolve towards gigantism over long periods of time, so at any given point in earth’s history when tetrapods had shown up and the climate had been stable for a while, you absolutely find giant animals.
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and remember, animals were actually still pretty giant until fairly recently on the geologic scale, a mere ten thousand years ago!
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the reason there are very few giant animals around now is that we’re actually living in a post-apocolyptic world. 
SOMETHING happened ten thousand years ago to wipe almost all of the ice-age megafauna off the planet, and we’re still not sure what. (and no, it wasn’t us.) but the first animals to fall in a mass extinction events are always the giants, because they require so much food! and it takes them tens of millions of years to show up again after a mass die-off. but give it another twenty million years or so, and giant animals will appear once again!
until then, please take a moment to appreciate whales.
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script-a-world · 4 years ago
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Do asteroids have an atmosphere? I sort of remember there was some giant worm on an asteroid in Star Wars? Or is this obviously a low Moh scale world building? Or any way I can possibly put life on an asteriod? Even if artificial?
Lockea: Inherently, what determines whether an object in space has an atmosphere or not depends on quite a few different factors. The biggest factor is simply gravity, but we also know that Earth’s molten core and magnetic fields contribute to how Earth keeps its atmosphere.
By definition, asteroids are not big enough for gravity fields.
Feral: Mynocks living inside a giant space worm living inside an asteroid inside an asteroid field with asteroids that are unusually close together probably all makes for pretty soft science fiction.
However, I don’t think asteroids must be devoid of life in harder works, particularly when we start talking about artificial life. It’s just that the life on the asteroids would not have evolved there.
The Expanse, both the books and SyFy show, handled this really well. Belters, or the people born on the asteroid belt in our solar system, are the descendents of immigrants from Earth, the same way the Martians are descendents of immigrants. Life on asteroids in the series is a hard one. The lack of natural atmosphere and gravity physically affects the people who are born and live on the asteroids, often causing deformities or debilitating conditions. This is part of the cycle of the socioeconomic oppression of the Belters by the Earth-born that is at the forefront of conflict in the series.
Synth: IIRC the asteroid worm in Star Wars is a silicon-based lifeform. Apparently so are mynocks, and since they can survive in the vacuum of space I guess the worms can too, so that’s one option for you: create alien life that does not need air air to survive. Feral mentioned that it’s unlikely life (as we currently understand it) would have evolved naturally on asteroids (as we currently understand them), but it could have arrived there via some form of panspermia: naturally via fragments of other life-bearing bodies, accidentally as a hitchhiker on a spacecraft, or deliberately introduced.
Can an asteroid have an atmosphere, though? Like with many of the space-themed Asks we’ve had in the past, the answer is: “Probably not but actually maybe?”
A lot depends on what you mean by “atmosphere”. If you’re thinking of what we’ve got on Earth, no, an asteroid won’t have that unless you play up the sci-fi aspects of your story and have it be artificially generated. If you just mean “a layer of gases around a celestial body,” then yes, an asteroid could potentially have an atmosphere. You probably wouldn’t be able to breathe it, though. Not for very long, anyway.
As Lockea said, the primary thing behind an astronomical body’s ability to hold on to an atmosphere is its gravity. Some other factors, among many, are the presence of a magnetic field, and the atmospheric temperature.
Gravity: asteroids, relative to planets, are tiny. They just haven’t got the gravitic oomph to hang onto any gases over the long term. The escape velocity — how fast something needs to go to get out of the object’s gravity well and into space — is low enough that the lighter atoms in the atmosphere can just leisurely fly away, or be very easily stripped off. The asteroid/dwarf planet Ceres does have an atmosphere of water vapour, but it is extremely delicate and only exists because it is constantly regenerating from sublimating surface ice, or possibly cryovolcanoes, or both. The solar wind strips it away about as fast as it respawns.
A strong, stable magnetic field protects a planet’s atmosphere from the constant onslaught of particles streaming out from the system’s sun, the aforementioned solar wind. One of the theories behind Mars’ thin atmosphere is its lack of protection by a magnetic field. Earth’s magnetic field acts as a buffer against the solar wind, deflecting it and preventing the molecules of our atmosphere from getting torn away, except a little bit at the poles. Mars hasn’t much of a magnetic field to speak of, so there isn’t anything running interference. Earth’s magnetic field is generated by the motion of the molten metals in the core of the planet. Mars doesn’t have that*. An asteroid doesn’t either. The moons Titan and Io don’t have notable magnetic fields of their own, but Saturn and Jupiter are huge planets with proportionally massive magnetic fields extending far enough to provide protection to their moons’ atmospheres.
*Mars may have had a magnetic field several billion years in its past, but has since lost it.
Remember the escape velocity bit mentioned in the “gravity” section? Here’s where temperature comes into play. Molecularly speaking, warmer things move faster. Warmer atmosphere = particles are moving faster = easier for them to achieve escape velocity and nyoom off into space. Mercury is roughly twice the diameter and some twenty-seven times the mass of Pluto, with an escape velocity over three-and-a-half times greater, and has a magnetic field whereas Pluto does not, yet Mercury has very little atmosphere to speak of (surface pressure of 1 nPa — one nanoPascale), while Pluto’s is noticeable (pressure varies but averages about 1 Pa, one thousand times higher than Mercury’s, and higher than the Moon’s). What’s the deal? Temperature. Mercury is extremely toasty, and Pluto is the polar (ha) opposite of that. Pluto’s less energetic atmospheric molecules can’t make it out of the gravity well, so they stay hugging the planet.
You have a few options for giving this asteroid an atmosphere:
Make it bigger/denser so it has more gravity and can hang onto its air. Problematic because gravity likes to make things round, so go past a certain mass and oops it’s a planet now I guess? Potentially takes a long while to reach equilibrium, though, so if you set the story early enough in the asteroid’s history, you could make it sound plausible.
A magnetic field for protection. Again unlikely to be natural, mostly due to the geological composition and structure of most asteroids, while potentially rife with various metals, precludes the existence of a molten core to act as a dynamo.
Locate it far away from any star so it isn’t subject to strong stellar winds, and it’s cold enough for the atmosphere to not drift away on its own. However the temperature extremes involved present their own problems regarding long-term habitability.
Mineralogical composition is such that it generates its own atmosphere via some kind of off-gassing (e.g. Ceres, mentioned earlier). Does come with a time-limit; resources on even a large asteroid are way more finite than on a planet.
Apply Handwavium™ as required to make it work the way you want, because you are the god of your story universe. Most people wouldn’t blink twice at an industrialized, inhabited asteroid if they came across it in a sci-fi tale. Also, Space Is Weird, so who’s to say there doesn’t exist a massive magnetic-field-having asteroid with a self-regenerating atmosphere and some kind of ecosystem somewhere out in the vast wilds of outer space?
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a-dinosaur-a-day · 5 years ago
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Inkayacu paracasensis
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By José Carlos Cortés 
Etymology: King of the Water
First Described By: Clarke et al., 2010
Classification: Dinosauromorpha, Dinosauriformes, Dracohors, Dinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoromorpha, Maniraptoriformes, Maniraptora, Pennaraptora, Paraves, Eumaniraptora, Averaptora, Avialae, Euavialae, Avebrevicauda, Pygostaylia, Ornithothoraces, Euornithes, Ornithuromorpha, Ornithurae, Neornithes, Neognathae, Neoaves, Aequorlitornithes, Ardeae, Aequornithes, Austrodyptornithes, Sphenisciformes, Spheniscidae
Status: Extinct
Time and Place: Between 37.2 and 33.9 million years ago, in the Priabonian age of the Eocene of the Paleogene 
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Inkayacu is known from Yumaque Point of the Otuma Formation in Ica, Peru 
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Physical Description: Inkayacu was an extinct penguin, and had a lot of similar traits to other extinct penguins - though resembling modern forms, extinct ones were unique in having extremely large bill size and just large body size in general. Inkayacu was about 1.5 meters long, which is a significant jump from the biggest living penguin (the Emperor Penguin at 1.2 meters long), and Inkayacu wasn’t even the biggest penguin at the time. It had a long, pointed bill, much longer than those seen on living members of the group. And - uniquely - we know the color of Inkayacu! Unlike living penguins, which are all varying shades of black and white with some splashes of other colors elsewhere, Inkayacu was grey and brown. We only known these colors form the flippers (wings), which show grey backs of the flipper and brown fronts, but it’s reasonable to suppose this pattern would follow the patterns of living penguins, where the color of the back of the flipper extends throughout the back of the animal, and the color of the front extends to the front. Thus, we depict Inkayacu with a grey back and a brown front, but this is still a conjecture. The melanosomes are similar to modern birds, long and narrow within the feathers - living penguins actually have wider ones. Other than that, the feathers of Inkayacu are similar to modern penguins in other ways, indicating that it had the same aquatic lifestyle. As such, it was flightless.
Diet: Inkayacu, like other penguins, would have fed on a wide variety of fish and aquatic invertebrates. 
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Icadyptes and Inkayacu by Apokryltaros, CC BY-SA 3.0 
Behavior: Though shaped in a lot of ways like living penguins, Inkayacu was different in a number of ways. It had fewer melanosomes in its feathers than living penguins - and these melanosomes provide rigidity in modern penguin feathers that help with deep-sea diving. Without such melanosomes, Inkayacu might not have been as well adapted to deep diving. Still, it was clearly adapted for spending its life in the sea, diving and sea-flying all over its habitat. It would have used its long beak to stab and grab food, especially slippery food that might be hard to get a grip on. Using its flippers, it could propel itself through the water. Its feet were small and not good for moving, so on land it would probably waddle. This is not an uncommon bird to find, fossil-wise, and so it stands to reason that it would have been very social like living penguins. It would have probably laid its eggs on land, and took care of its young with mated partners. Given it lived in Peru, in the Eocene, it was more adapted for warm weather than cold, and wouldn’t have ventured very far south. 
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By Julio Lacerda, used with permission from Earth Archives 
Ecosystem: Inkayacu lived along the Pervuian Priabonian coast, the Western coast of South America right as the global rainforest of the Eocene was collapsing and being replaced with more varying and arid climates. This was also a time of notable climate change and effects on the ocean, leading to a small mass extinction (especially in the oceans) at this time - killing off many iconic forms, including proto-whales. The conditions of this mass extinction actually allowed the penguins to flourish, and Inkayacu was a part of that flourishing. Inkayacu lived alongside proto-whales like Cynthiacetus and Mystacodon - a toothed baleen whale. Inkayacu wasn’t the only penguin in this area, but was joined by the larger and longer-beaked Icadyptes. As for proper fish, there were ray-finned fish like Engraulis and Sardinops, and unnamed sharks. There may have also been the marine snake Pterosphenus. There were many kinds of invertebrates as well. Inkayacu would probably have had to look out for the sharks and whales, though the fish would have had to look out for it! The coast that Inkayacu would have spent its time on would probably have been more rocky than sandy, though it’s uncertain either way. 
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By Ripley Cook 
Other: Inkayacu is very closely related to living penguins and is just outside the group of modern penguins and their closest relatives, so it showcases the evolution of penguins towards what we’re familiar with today. It’s interesting to note that short beaks seem to be characteristic of the modern crown group of penguins, and that long beaks were found in penguins even as close to the crown group as Inkayacu.
~ By Meig Dickson
Sources under the Cut 
Acosta Hospitaleche, C., and M. Stucchi. 2005. Nuevos restos terciarios de Spheniscidae (Aves, sphenisciformes) procedentes de la Costa del Peru. Revista española de paleontología 20(1):1-5
Clarke, J.A.; Ksepka, D.T.; Stucchi, M.; Urbina, M.; Giannini, N.; Bertelli, S.; Narváez, Y.; Boyd, C.A. (2007). "Paleogene equatorial penguins challenge the proposed relationship between biogeography, diversity, and Cenozoic climate change". Proceedings of the National Academy of Sciences. 104 (28): 11545–11550.
Clarke, J. A., D. T. Ksepka, R. Salas-Gismondi, A. J. Altamirano, M. D. Shawkey, L. D’Alba, J. Vinther, T. J. DeVries, and P. Baby. 2010. Fossil evidence for evolution of the shape and color of penguin feathers. Science 330
Hoffstetter, R. 1958. Un serpent marin du genre Pterosphenus (Pt. Sheppardi nov. sp.) dans L’Éocène supérieur de L’Équateur (Amérique de Sud). Bulletin de la Société Géologique de France 6:45-50
Hooker, J.J.; Collinson, M.E.; Sille, N.P. (2004). "Eocene-Oligocene mammalian faunal turnover in the Hampshire Basin, UK: calibration to the global time scale and the major cooling event". Journal of the Geological Society. 161 (2): 161–172.
Ivany, Linda C.; Patterson, William P.; Lohmann, Kyger C. (2000). "Cooler winters as a possible cause of mass extinctions at the Eocene/Oligocene boundary". Nature. 407 (6806): 887–890.
Köhler, M; Moyà-Solà, S (December 1999). "A finding of oligocene primates on the European continent". Proceedings of the National Academy of Sciences of the United States of America. 96 (25): 14664–7.
Li, Y. X.; Jiao, W. J.; Liu, Z. H.; Jin, J. H.; Wang, D. H.; He, Y. X.; Quan, C. (2016-02-11). "Terrestrial responses of low-latitude Asia to the Eocene–Oligocene climate transition revealed by integrated chronostratigraphy". Clim. Past. 12 (2): 255–272.
Marocco, R., and C. d.e. Muizon. 1988. Los vertebrados del Neogeno de La Costa Sur del Perú: Ambiente sedimentario y condiciones de fosilización. Bulletin de l'Institut Frances d'Etudes Andines 17(2):105-117
Martinez-Cacers, M., and C. de Muizon. 2011. A toothed mysticete from the Middle Eocene to Lower Oligocene of the Pisco Basin, Peru: new data on the origin and feeding evolution of Mysticeti. Sixth Triennial Conference on Secondary Adaptation of Tetrapods to Life in Water 56-57
Molina, Eustoquio; Gonzalvo, Concepción; Ortiz, Silvia; Cruz, Luis E. (2006-02-28). "Foraminiferal turnover across the Eocene–Oligocene transition at Fuente Caldera, southern Spain: No cause–effect relationship between meteorite impacts and extinctions". Marine Micropaleontology. 58 (4): 270–286.  
Shackleton, N. J. (1986-10-01). "Boundaries and Events in the Paleogene Paleogene stable isotope events". Palaeogeography, Palaeoclimatology, Palaeoecology. 57 (1): 91–102.
Vinther, J., D. E. G. Briggs, R. O. Prum, V. Saranathan. 2008. The colour of fossil feathers. Biology Letters 4 (5): 522 - 525.
Zachos, James C.; Quinn, Terrence M.; Salamy, Karen A. (1996-06-01). "High-resolution (104 years) deep-sea foraminiferal stable isotope records of the Eocene-Oligocene climate transition". Paleoceanography. 11 (3): 251–266.
Zhang, R.; Kravchinsky, V.A.; Yue, L. (2012). "Link between Global Cooling and Mammalian Transformation across the Eocene-Oligocene Boundary in the Continental Interior of Asia]". International Journal of Earth Sciences. 101 (8): 2193–2200.
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shirlleycoyle · 4 years ago
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The End of the Oil Age Is Upon Us
The oil industry is on the cusp of a process of almost total decimation that will begin over the next 30 years, and continue through to the next century. That’s the stark implication of a new forecast by a team of energy analysts led by a former US government energy advisor, seen exclusively by Motherboard.  
2020, the forecast suggests, will go down in history as the final point-of-no-return for the global oil industry—a date to which we will look back and remember how the production of oil, as well as other fossil fuels like gas and coal, underwent a slow, but inexorable and largely irreversible decline.  
Along the way, some 80 percent of the industry as we know it is going to be wiped out. 
Of course, the COVID-19 pandemic is likely to be recognized as a principal trigger for this decline. The new era of oscillating social distancing rules and remote working has crushed once rocketing demand, at least temporarily.  
But in reality, the broad contours of this decline were already set in motion even before the pandemic hit. And the implications are stark: we are in the midst of a fundamental energy transition which will see the bulk of the fossil fuel industry gradually eclipsed in coming decades.  
The end of the line 
These conclusions are laid out in a soon-to-be-published analysis written by a former top strategy advisor to the US Department of Energy, Rodrigo Villamizar Alvargonzález—previously Columbian Minister of Energy, World Bank senior economic consultant, an advisor to the Dutch Ministry of Foreign Affairs, and energy expert for the Texas State Senate Economic Development Committee and Texas Public Utility Commission.  
I obtained the draft manuscript, titled Energy and Power Futures, from the authors earlier this year when it was first finalized in January—just before the COVID-19 pandemic came on the scene. Villamizar’s forecast placed “the start date of oil’s decline at around 2020”—described as a “tipping point” for world oil production which, from then on “will go down. Nowhere in sight is the possibility of going over the all-time production high of 35.7 billion barrels per year (or 100 million barrels per day) beyond 2020.”  
Villamizar is currently Head of Strategy for the Americas at Kaiserwetter Energy Asset Management, an energy investment firm based in Hamburg, Madrid, and New York. His analysis is co-authored with Randy Willoughby, a professor of political science at San Diego University, and Vicente Lopez-Ibor Mayor, previously founding Chairman of Europe’s largest solar energy company Lightsource BP (owned by oil and gas giant BP) and a former Commissioner at Spain’s National Energy Commission. Their study is due to be published later this year by Durham University’s School of Government and International Affairs. 
After the COVID-19 crisis, they revised their forecasts—finding that the pandemic has reinforced the trends they had previously identified. In their updated text, they argue that the remaining years of the 21st century and beyond will be marked by a “slow but permanent decline in demand for plenty of oil resources.” 
The new forecast is in broad agreement with the predictions of several other agencies, including the Norwegian energy consultancy DNV GL, the US financial consultancy McKinsey, and even oil and gas giant BP, which similarly portend a relentless decline in oil demand out to 2050. 
But unlike those predictions, the forecast shows this decline could be faster, with huge ramifications for global oil production. 
Too much oil? 
In the view of Villamizar, Willoughby and Mayor, this is not an oil scarcity crisis, but a demand crisis. They write: “Perhaps we were the first to notice that, even before COVID-19, the year 2019 would be the last ever to register daily production of oil closer to 100 million barrels. Indeed, before the coronavirus landed in Italy, the size of the oil market had already started its permanent slippery downward slide towards an uncertain future.” 
In this analysis, oil demand was seen to peak at the end of 2019 and early 2020. “I thought we had a glitch in our forecasting model,” explained Villamizar. “But all the revisions pointed to a similar result.”  
Among the factors behind the portended decline are a combination of “climate change action initiatives” demanding a brake on fossil fuel production; a shift toward more electric cars and other forms of transport; the persistence of lower oil prices undermining oil industry profitability; and a decrease in investment in new oil infrastructure and technology: 
“Our results showed petroleum consumption reduced 31 percent by 2050 and 60 percent by 2100. That means that 2019 was the highest ever production level reached (100 million barrels per day, mbd).” 
Villamizar and his colleagues point out that oil will still be needed for many key industries, including petrochemicals and plastics.  
And there are vast reserves of oil still in the ground. So the industry will not simply disappear. But most of the world’s oil assets will, in their view, become ‘stranded’—left alone because global demand for it gradually evaporates.
The overall prognosis—that we are now moving into the second and final half of the oil age—is sobering: “Oil will not die anytime soon but it is already on a downward slippery slope.” 
Natural selection 
While the oil industry as such will not simply collapse, these experts believe it is now entering a protracted period of terminal decline over the next three decades. What emerges as a consequence will be a very different type of industry. 
“We forecast a long-term Darwinian transformation in the future oil sector,” write Villamizar, Willoughby, and Mayor. “The new market structure rising from the old oil reality will be dominated by an oil troika made up of US, Saudi Arabia, and Russia.”  
Only 20 percent of industry players will survive by 2050, they forecast. And the oil market will be “one-third smaller than today.”  
This drop in demand means, of course, that global oil production will also decline because it is no longer needed. According to the authors, production will decline from 100 million barrels per day (mbd) to 68-69 mbd by mid-century, and 40 mbd by 2100.  
The world will simultaneously see a dramatic reduction of exports from 46 mbd to about 25 mbd by 2050, and a reduction in the number of exporting countries from today’s 58 to about 15.  
These projected declines in global oil production by a third, and in global oil exports by nearly half—within the next 30 years—comprises a colossal collapse by any standard.  
The analysts compare this sweeping oil sector transformation to the decimation of the tobacco industry. This time, the result will be “fewer players, shrinking markets and lots of enemies everywhere accusing the companies of selling an environmentally poisonous product… With less water in a shrinking pond, the bigger fish will push the smaller out and regroup in isolated sections of what’s left.” 
Climate danger 
But it is too early to rejoice that the coming decimation of the oil industry will happen sufficiently fast to save us from dangerous climate change.  
Villamizar, Willoughby, and Mayor point out that “this future lower level of oil supply is still much higher than what the Paris Agreement on climate mitigation expects to be produced to maintain the world’s average temperature above no higher than 2 degree Celsius from the level registered during the Industrial Revolution.” 
So it would be a huge mistake to sit back and wait casually for the oil industry to slowly die out. That approach would put us on a path to breach the scientifically recognized 2C safe limit. Beyond that level, scientists warn that we will experience an increasingly deadly and unpredictable climate. 
And some scientists warn that even now, due to the uncertainties in predicting how tightly interconnected complex ecosystems might unfold, we may already be on the brink of triggering a runaway warming process that could culminate in an uninhabitable planet. 
This predicament puts the task of rapidly decarbonizing our economy at the forefront of global priorities. That will, according to Villamizar and his co-authors, require huge investments in “areas like electrification, affordable long-term energy storage, and regenerative agriculture.”  
It also means a change in investor mindsets, and thus a shift to a slower but perhaps more stable economy—instead of expecting quick bucks for the next quarter, investors should recognize the need to wait 10-15 years for returns, they argue.  
Supply or demand? 
While the demand slump is right now the big factor in the global oil crisis, several other studies have pointed out that the oil industry was overdue a reckoning due to the increasing costs of oil production and how this might impact supply relative to profits.  
Earlier in February, I reported on a major study by the Geological Survey of Finland which assessed the implications of the fact that conventional oil production began to plateau around 2005. After this point, the world has become increasingly dependent on unconventional oil and gas supplies. Since 2008, the rise in demand has been met almost entirely by more expensive and difficult to extract sources such as shale oil, tar sands and offshore drilling.  
While market prices have remained too low for oil companies to make a meaningful profit relative to rocketing extraction and production costs, they have ramped up billions of dollars in debt to keep the show on the road: all enabled by massive post-2008 quantitative easing. Thus, the study warned: 
“The era of cheap and abundant energy is long gone. Money supply and debt have grown faster than the real economy. Debt saturation and paralysis is now a very real risk, requiring a global scale reset.” 
In June, a peer-reviewed study led by Dr Roger Bentley of the Petroleum Analysis Centre in Ireland found that global conventional oil production had indeed reached a “resource-limited plateau” from 2005 onwards. Although this was relieved by the rise in US shale oil, even before the pandemic there were signs that the shale boom “may be fairly short-lived.” 
The new forecast from Villamizar and his co-authors, when taken into context with such studies, suggests that the oil industry now faces a perfect storm of crises affecting both supply and demand. 
Production was increasingly uneconomical due to the transition to more expensive and difficult to extract unconventional oil and gas. The unsustainable debt-drenched economics of unconventional resources mean that, however vast those reserves are, it was increasingly unviable to continue extraction without even more unsustainable levels of debt. Meanwhile, global demand was already set to begin a slow but precipitous decline from 2020 onwards. But the pandemic accelerated that collapse in demand, and we have reached the point-of-no-return.
If this analysis is right, then the end of the oil age is in full swing. The real question is, how fast can we transition to what comes next?
The End of the Oil Age Is Upon Us syndicated from https://triviaqaweb.wordpress.com/feed/
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brightovate · 5 years ago
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Earth Science Literacy
Earth Science Literacy
The Big Ideas and Supporting Concepts of Earth Science
Each big idea is backed by supporting concepts comparable to those underlying the National Science Education Standards and the American Association for the Advancement of Science Benchmarks for Science Literacy
Big Idea 1. Earth scientists use repeatable observations and testable ideas to understand and explain our planet.
1.1 Earth scientists find solutions to society’s needs. Earth scientists work on challenging problems that face humanity on topics such as climate change and human impacts on Earth. Earth scientists successfully predict hazards to humans and locate and recover natural resources, making possible the flourishing of humans on Earth. 1.2 Earth scientists use a large variety of scientific principles to understand how our planet works. Earth scientists combine the study of Earth’s geology with aspects of biology, chemistry, physics, and mathematics in order to understand the complexities of the Earth system. 1.3 Earth science investigations take many different forms. Earth scientists do reproducible experiments and collect multiple lines of evidence. This evidence is taken from the field, analytical, theoretical, experimental, and modeling studies. 1.4 Earth scientists must use indirect methods to examine and understand the structure, composition, and dynamics of Earth’s interior. With the exception of wells and mine shafts drilled into the Earth, direct observations of Earth’s interior are not possible. Instead, Earth scientists observe the interior of the planet using seismic waves, gravity, magnetic fields, radar, sonar, and laboratory experiments on the behavior of materials at high pressures and temperatures. 1.5 Earth scientists use their understanding of the past to forecast Earth’s future. Earth science research tells us how Earth functioned in the past under conditions not seen today and how conditions are likely to change in the future. 1.6 Earth scientists construct models of Earth and its processes that best explain the available geological evidence. These scientific models, which can be conceptualized or analytical, undergo rigorous scrutiny and testing by collaborating and competing groups of scientists around the world. Earth science research documents are subjected to rigorous peer review before they are published in scientific journals. 1.7 Technological advances, breakthroughs in interpretation, and new observations continually refine our understanding of Earth. This Earth Science Literacy framework must be a living document that grows along with our changing ideas and concepts of Earth.
Big Idea 2. The earth is 4.6 billion years old.
2.1 Earth’s rocks and other materials provide a record of its history. Earth scientists use the structure, sequence, and properties of rocks, sediments, and fossils to reconstruct events in Earth’s history. The decay rates of radioactive elements are the primary means of obtaining numerical ages of rocks and organic remains. Understanding geologic processes active in the modern world are crucial to interpreting Earth’s past. 2.2 Our Solar System formed from a vast cloud of gas and dust 4.6 billion years ago. Some of this gas and dust were the remains of the supernova explosion of a previous star; our bodies are therefore made of “stardust.” This age of 4.6 billion years is well established from the decay rates of radioactive elements found in meteorites and rocks from the Moon. 2.3 Earth formed from the accumulation of dust and gas, and multiple collisions of smaller planetary bodies. Driven by gravity, Earth’s metallic core formed as iron sank to the center. Rock surrounding the core was mostly molten early in Earth’s history and slowly cooled to form the Earth’s mantle and crust. The atoms of different elements combined to make minerals, which combined to make rocks. The earth’s ocean and the atmosphere began to form more than 4 billion years ago from the rise of lighter materials out of the mantle. 2.4 Earth’s crust has two distinct types: continental and oceanic. Continental crust persists at Earth’s surface and can be billions of years old. Oceanic crust continuously forms and recycles back into the mantle; in the ocean, it is nowhere older than about 200 million years. 2.5 Studying other objects in the solar system helps us learn Earth’s history. Active geologic processes such as plate tectonics and erosion have destroyed or altered most of the Earth’s early rock records. Many aspects of Earth’s early history are revealed by objects in the solar system that have not changed as much as Earth has. 2.6 Life on Earth began more than 3.5 billion years ago. the fossils indicate that life began with single-celled organisms, which were the only life forms for billions of years. Humans (Homo sapiens) have existed for only a very small fraction (about 0.004%) of Earth’s history. 2.7 Over Earth’s vast history, both gradual and catastrophic processes have produced enormous changes. Super-continents formed and broke apart, the compositions of the atmosphere and ocean changed, sea level rose and fell, living species evolved and went extinct, ice sheets advanced and melted away, meteorites slammed into Earth, and the mountains formed and eroded away.
Big Idea 3. Earth is a complex system of interacting rock, water, air, and life.
3.1 The four major systems of Earth are the geosphere, hydrosphere, atmosphere, and biosphere. The geosphere includes a metallic core, solid and molten rock, soil, and sediments. The atmosphere is the envelope of gas surrounding Earth. The hydrosphere includes the ice, water vapor, and liquid water in the atmosphere, the ocean, lakes, streams, soils, and groundwater. The biosphere includes Earth’s life, which can be found in many parts of the geosphere, hydrosphere, and atmosphere. Humans are part of the biosphere, and human activities have important impacts on all four spheres. 3.2 All Earth processes are the result of energy flowing and mass cycling within and between Earth’s systems. This energy is derived from the sun and the Earth’s interior. The flowing energy and cycling matter cause chemical and physical changes in Earth’s materials and living organisms. For example, large amounts of carbon continually cycle among systems of rock, water, air, organisms, and fossil fuels such as coal and oil. 3.3 Earth exchanges mass and energy to the rest of the Solar System. Earth gains and loses energy through incoming solar radiation, heat loss to space, and gravitational forces of the sun, moon, and planets. Earth gains mass from the impacts of meteoroids and comets and loses mass by the escape of gases into space. 3.4 Earth’s systems interact over a wide range of temporal and spatial scales. These scales range from microscopic to global in size and operate over fractions of a second to billions of years. These interactions among Earth’s systems have shaped Earth’s history and will determine the Earth’s future. 3.5 Regions where organisms actively interact with each other and their environment is called ecosystems. Ecosystems provide the goods (food, fuel, oxygen, and nutrients) and services (climate regulation, water cycling and purification, and soil development and maintenance) necessary to sustain the biosphere. Ecosystems are considered the planet’s essential life-support units. 3.6 Earth’s systems are dynamic; they continually react to changing influences. Components of Earth’s systems may appear stable, change slowly over long periods of time, or change abruptly with significant consequences for living organisms. 3.7 Changes in part of one system can cause new changes to that system or to other systems, often in surprising and complex ways. These new changes may take the form of “feedbacks” that can increase or decrease the original changes and can be unpredictable and/or irreversible. Deep knowledge of how most feedbacks work within and between Earth’s systems is still lacking. 3.8 Earth’s climate is an example of how complex interactions among systems can result in relatively sudden and significant changes. The geologic record shows that the interactions between tectonic events, solar inputs, planetary orbits, ocean circulation, volcanic activity, glaciers, vegetation, and human activities can cause appreciable, and in some cases rapid, changes in global and regional patterns of temperature and precipitation.
Big Idea 4. Earth is continuously changing.
4.1 Earth’s geosphere changes through geological, hydrological, physical, chemical, and biological processes that are explained by universal laws. These changes can be small or large, continuous or sporadic, and gradual or catastrophic. 4.2 Earth, like other planets, are still cooling, though radioactive decay continuously generates internal heat. This heat flows through and out of Earth’s interior largely through convection, but also through conduction and radiation. The flow of Earth’s heat is like its lifeblood, driving its internal motions. 4.3 Earth’s interior is in constant motion through the process of convection, with important consequences for the surface. Convection in the iron-rich liquid outer core, along with Earth’s rotation around its axis, generates Earth’s magnetic field. By deflecting solar wind around the planet, the magnetic field prevents the solar wind from stripping away Earth’s atmosphere. Convection in the solid mantle drives the many processes of plate tectonics, including the formation and movements of the continents and oceanic crust. 4.4 Earth’s tectonic plates consist of the rocky crust and uppermost mantle and move slowly with respect to one another. New oceanic plate continuously forms at mid-ocean ridges and other spreading centers, sinking back into the mantle at ocean trenches. Tectonic plates move steadily at rates of up to 10 centimeters per year. 4.5 Many active geologic processes occur at plate boundaries. Plate interactions change the shapes, sizes, and positions of continents and ocean basins, the locations of mountain ranges and basins, the patterns of ocean circulation and climate, the locations of earthquakes and volcanoes, and the distribution of resources and living organisms. 4.6 Earth materials take many different forms as they cycle through the geosphere. Rocks form from the cooling of magma, the accumulation and consolidation of sediments, and the alteration of older rocks by heat, pressure, and fluids. These three processes form igneous, sedimentary, and metamorphic rocks. 4.7 Landscapes result from the dynamic interplay between processes that form and uplift new crusts and processes that destroy and depress the crust. This interplay is affected by gravity, density differences, plate tectonics, climate, water, the actions of living organisms, and the resistance of Earth materials to weathering and erosion. 4.8 Weathered and unstable rock materials erode from some parts of Earth’s surface and are deposited in others. Under the influence of gravity, rocks fall downhill. Water, ice, and the air carry eroded sediments to lower elevations, and ultimately to the ocean. 4.9 Shorelines move back and forth across continents, depositing sediments that become the surface rocks of the land. Through dynamic processes of plate tectonics and glaciation, Earth’s sea level rises and falls by up to hundreds of meters. This fluctuation causes shorelines to advance and recede by hundreds of kilometers. The upper rock layers of most continents formed when rising sea levels repeatedly flooded the interiors of continents.
Big Idea 5. Earth is the water planet.
5.1 Water is found everywhere on Earth, from the heights of the atmosphere to the depths of the mantle. Early in Earth’s history, surface water accumulated through both outgoing from its interior and the capture of some extraterrestrial ice. Water vapor in the atmosphere condensed and rained out as the planet cooled. 5.2 Water is essential for life on Earth. Earth is unique in our Solar System in that water has coexisted at the Earth’s surface in three phases (solid, liquid, and gas) for billions of years, allowing the development and continuous evolution of life. 5.3 Water’s unique combination of physical and chemical properties are essential to the dynamics of all of Earth’s systems. These properties include the manner in which water absorbs and releases heat, reflects sunlight, expands upon freezing, and dissolves other materials. 5.4 Water plays an important role in many of the Earth’s deep internal processes. Water allows the rock to melt more easily, generating much of the magma that erupts as lava at volcanoes. Water facilitates the metamorphic alteration of rock and is integral to plate tectonic processes. 5.5 Earth’s water cycles among the reservoirs of the atmosphere, streams, lakes, ocean, glaciers, groundwater, and deep interior of the planet. The total amount of water on the Earth’s surface has remained fairly constant over geologic time, although its distribution among reservoirs has varied. 5.6 Water shapes landscapes. Flowing water in streams strongly shapes the land surface through weathering, erosion, transport, and deposition. Water participates in both the dissolution and formation of Earth’s materials. 5.7 Ice is an especially powerful agent of weathering and erosion. Water expands as it freezes, widening cracks and breaking apart rocks. Movement of massive glaciers can scour away land surfaces. The flowing ice of glaciers covers and alters vast areas of continents during Ice Ages. 5.8 Freshwater is less than 3% of the water of the Earth’s surface. Most of this fresh water is stored as glaciers in Antarctica and Greenland. Less than 1% of Earth’s near-surface water is drinkable liquid freshwater, and about 99% of this water is in the form of groundwater in the pores and fractures within the soil, sediment, and rock.
Big Idea 6. Life evolves on a dynamic Earth and continuously modifies Earth.
6.1 Fossils are the preserved evidence of ancient life. Fossils document the presence of life early in Earth’s history and the subsequent evolution of life over billions of years. 6.2 Evolution, including the origination and extinction of species, is a natural and ongoing process. Changes to Earth and its ecosystems determine which individuals, populations, and species survive. As an outcome of dynamic Earth processes, life has adapted through evolution to new, diverse, and ever-changing niches. 6.3 Biological diversity, both past, and present is vast and largely undiscovered. A new species of living and fossil organisms are continually finding and identified. All of this diversity is interrelated through evolution. 6.4 More complex life forms and ecosystems have arisen over the course of Earth’s history. This complexity has emerged in association with adaptations to new and constantly changing habitats. But not all evolution causes greater complexity; organisms adapting to changing local environments may also become simpler. 6.5 Microorganisms dominated Earth’s early biosphere and continue today to be the most widespread, abundant, and a diverse group of organisms on the planet. Microbes change the chemistry of Earth’s surface and play a critical role in nutrient cycling within most ecosystems. 6.6 Mass extinctions occur when global conditions change faster than species in large numbers can adapt. Mass extinctions are often followed by the origination of many new species over millions of years as surviving species evolve and fill vacated niches. 6.7 The particular life forms that exist today, including humans, are a unique result of the history of Earth’s systems. Had this history been even slightly different, modern life forms might be entirely different and humans might never have evolved. 6.8 Life changes the physical and chemical properties of Earth’s geosphere, hydrosphere, and atmosphere. Living organisms produced most of the oxygen in the atmosphere through photosynthesis and provided the substance of fossil fuels and many sedimentary rocks. The fossil record provides a means for understanding the history of these changes. 6.9 Life occupies a wide range of Earth’s environments, including extreme environments. Some microbes live in rocks kilometers beneath the surface, within glacial ice, and at seafloor vents where hot fluids escape from the oceanic crust. Some of these environments may be similar to the conditions under which life originated, and to environments that exist on other planets and moons.
Big Idea 7. Humans depend on Earth for resources.
7.1 Earth is our home; its resources mold civilizations, drive human exploration and inspire human endeavors that include art, literature, and science. We depend upon Earth for sustenance, comfort, places to live and play, and spiritual inspiration. 7.2 Geology affects the distribution and development of human populations. Human populations have historically concentrated at sites that are geologically advantageous to commerce, food production, and other aspects of civilization. 7.3 Natural resources are limited. The earth’s natural resources provide the foundation for all of human society’s physical needs. Most are nonrenewable on human time scales, and many will run critically low in the near future. 7.4 Resources are distributed unevenly around the planet. Resource distribution is a result of how and where geologic processes have occurred in the past and have extremely important social, economic, and political implications. 7.5 Water resources are essential for agriculture, manufacturing, energy production, and life. Earth scientists and engineers find and manage our freshwater resources, which are limited in supply. In many places, humans withdraw both surface water and groundwater faster than they are replenished. Once fresh water is contaminated, its quality is difficult to restore. 7.6 Soil, rocks, and minerals provide essential metals and other materials for agriculture, manufacturing, and building. Soil develops slowly from weathered rock, and the erosion of soil threatens agriculture. Minerals and metals are often concentrated in very specific ore deposits. Locating and mining these ore deposits provide the raw materials for much of our industry. Many electronic and mechanical devices have specific requirements for particular rare metals and minerals that are in short supply. 7.7 Earth scientists and engineers develop new technologies to extract resources while reducing pollution, waste, and ecosystem degradation caused by extraction. For example, land reclamation can partially restore surface environments following surface mining. 7.8 Oil and natural gas are unique resources that are central to modern life in many different ways. They are the precursors to chemicals used to make numerous products, such as plastics, textiles, medications, and fertilizers. Petroleum sources are needed to manufacture most industrial products. 7.9 Fossil fuels and uranium currently provide most of our energy resources. Fossil fuels, such as coal, oil, and natural gas, take tens to hundreds of millions of years to form. Their abundance will make them the dominant source of energy in the near future. New sources, such as methane hydrates, are being explored. 7.10 Earth scientists help society move toward greater sustainability. Renewable energy sources, such as solar, wind, hydroelectric, and geothermal, are being developed. They will replace fossil fuels as those become scarcer, more expensive to retrieve from Earth, and undesirable due to environmental damage. Earth scientists foster global cooperation and science-informed stewardship that can help to ensure the availability of resources for future generations.
Big Idea 8. Natural hazards pose risks to humans.
8.1 Natural hazards result from natural Earth processes. These hazards include earthquakes, tsunamis, hurricanes, floods, droughts, landslides, volcanic eruptions, extreme weather, lightning-induced fires, sinkholes, coastal erosion, and comet and asteroid impacts. 8.2 Natural hazards shape the history of human societies. Hazardous events can significantly alter the size of human populations and drive human migrations. Risks from the natural hazards increase as populations expand into vulnerable areas or concentrate on already-inhabited areas. 8.3 Human activities can contribute to the frequency and intensity of some natural hazards. These hazards include floods, landslides, droughts, forest fires, and erosion. 8.4 Hazardous events can be sudden or gradual. They range from sudden events such as earthquakes and explosive volcanic eruptions to more gradual phenomena such as droughts, which may last decades or longer. Changes caused by continual processes such as erosion and land subsidence can also result in risks to human populations, as with the increased risk of flooding in New Orleans. 8.5 Natural hazards can be local or global in origin. Local events can have distant impacts because of the interconnectedness of both human societies and Earth’s systems. For example, a volcanic eruption in the Pacific Ocean can impact the climate around the globe. 8.6 Earth scientists are continually improving estimates of when and where natural hazards occur. This analysis is done through continuous monitoring Earth, increasing our understanding of the physical processes that underlie its changes, and developing scientific models that can explain hazard-related scientific observations. 8.7 Humans cannot eliminate natural hazards but can engage in activities that reduce their impacts. Loss of life, property damage, and economic costs can be reduced by identifying high-risk locations and minimizing human habitation and societal activities in them, improving construction methods, developing warning systems, and recognizing how human behavior influences preparedness and response. 8.8 An Earth-science-literate public is essential for reducing risks from natural hazards. This literacy leads to the promotion of community awareness about natural hazards and to the development of scientifically informed policies that reduce risk.
Big Idea 9. Humans significantly alter the Earth.
9.1 Human activities significantly change the rates of many of the Earth’s surface processes. Humankind has become a geological agent that must be taken into account equally by natural processes in any attempt to understand the workings of Earth’s systems. As human populations and per capita consumption of natural resources increase, so do our impacts on the Earth’s systems. 9.2 Earth scientists use the geologic record to distinguish between natural and human influences on the Earth’s systems. Evidence of natural and human influences on Earth processes is found in ice cores and soils, and in the lake, estuary, and ocean sediments. 9.3 Humans cause global climate change through fossil fuel combustion, land-use changes, agricultural practices, and industrial processes. The consequences of global climate change include melting glaciers and permafrost, rising sea levels, shifting precipitation patterns, increased forest fires, more extreme weather, and the disruption of global ecosystems. 9.4 Humans affect the quality, availability, and distribution of Earth’s water through the modification of streams, lakes, and groundwater. Engineered structures such as canals, dams, and levees significantly alter water and sediment distribution. Pollution from sewage runoff, agricultural practices, and industrial processes reduce water quality. Overuse of water for electric power generation and agriculture reduces water availability for drinking. 9.5 Human activities alter the natural land surface. Humans use more than one-third of the land’s surface not covered with ice to raise or grow their food. Large areas of land, including delicate ecosystems such as wetlands, are transformed by human land development. These land surface changes impact many Earth processes such as groundwater replenishment and weather patterns. 9.6 Human activities accelerate land erosion. At present, the rate of global land erosion caused by human activities exceeds all-natural processes by a factor of ten. These activities include urban paving, removal of vegetation, surface mining, stream diversions, and increased rain acidity. 9.7 Human activities significantly alter the biosphere. Earth is experiencing a worldwide decline in biodiversity—a modern mass extinction—due to loss of habitat area and high rates of environmental change caused by human activities. The rates of extinctions are now comparable to the rates of mass extinctions in the geologic past. 9.8 Earth scientists document and seek to understand the impacts of humans on global change over short and long time spans. Many of these human impacts on Earth’s systems are not reversible over human lifetimes, but through human cooperation, their impacts on future generations can be lessened and even reversed. 9.9 An Earth-science-literate public, informed by current and accurate scientific understanding of Earth, is critical to the promotion of good stewardship, sound policy, and international cooperation. Earth science education is important for individuals of all ages, backgrounds, and nationalities.
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dorcasrempel · 5 years ago
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Continuing a legacy of Antarctic exploration
When Robert F. Scott’s Discovery expedition began exploring the Antarctic continent in 1901, they set out to geographically and scientifically characterize the regions touched by the Ross Sea. As the group of naval officers and scientists set foot upon the Ross Ice Shelf, they mapped their travels and completed surveys, collecting biological specimens for further study.
Two polar explorers and physicians on the expedition, Reginald Koettlitz and Edward Wilson, noticed microbial mats composed of cyanobacteria growing along the edges of shallow freshwater ponds on the McMurdo Ice Shelf in and around Ross Island. In the name of natural science, they sampled them, and the preserved mats spent nearly the next century in the collections of London’s Natural History Museum. Now a new comparison of contemporary lipids with those old samples is shedding light on the evolution of complex life, and that which existed during the planet’s “Snowball Earth” phase.
In 2017, Anne Jungblut, a life sciences researcher at the museum, examined Koettlitz’s and Wilson’s mats to study whether Antarctica’s cyanobacterial diversity had changed since the Discovery expedition by comparing them to modern mats from the same region. Her results showed that, for the most part, the microbial community remained stable, with slow genetic turnover — a testament to the cyanobacteria’s resilience on the icy continent.
Roger Summons, the Schlumberger Professor of Geobiology in the Department of Earth, Atmospheric and Planetary Sciences (EAPS), traveled to Antarctica in 2018 with colleagues Ian Hawes of the University of Waikato and Marc Schallenberg of the University of Otago in New Zealand to take a first-hand look at the types of environments in which these microbial mats thrive. The trio ventured to Bratina Island, which is surrounded by the Ross Ice Shelf. There, the meltwater ponds form in the midst of “dirty ice,” debris-covered slopes of ice and volcanic rock.
“The ponds have liquid water, though there a few ponds that have thin layers of ice over them — and its full-on sunlight,” Summons says. “What a phenomenal challenge it would have been for the early explorers to carry equipment across this place because of its precipices, holes, miserable weather, and wind.”
The unique topography of the glacial environment results from a vertical conveyer-belt mechanism that moves sediment from the sea bed up to the surface of McMurdo Ice Shelf. While wind causes the ice’s surface to ablate — to evaporate or melt — seawater freezes beneath the ice shelf, sometimes trapping sea sediments and organisms in the ice. As more ice ablates at the surface over time, material from the sea beneath is transported upwards over long time scales, accumulating at the surface. In Antarctica, Summons saw ancient sponges and bryozoans — aquatic invertebrates that once grew in the water beneath the ice — scattered among the sediments. And, like Koettlitz and Wilson, Summons and his colleagues sampled the microbial mats thriving in the ephemeral meltwater ponds.
Thomas Evans, a postdoc in the EAPS Summons lab, has been studying these microbial communities because of their potential as models for the evolution of complex life on Earth during the Cryogenian Period, an enigmatic geologic time-slice that took place 720-635 million years ago. “These oases of life in high latitude ecosystems are of interest because they might serve as analogs to those that existed when the Earth experienced two long-lasting glaciations of global extent,” Evans says.
These glaciations play a central role in the version of the Snowball Earth hypothesis described by Paul Hoffman, professor emeritus at Harvard University. The hypothesis delineates scenarios in which the Earth becomes entirely or almost entirely covered by ice, putting the brakes on biological productivity. But those icy events didn’t quite halt the existence or radiation of life.
“I’ve always been interested in the evolution of animals after the Cryogenian,” Summons says. “Why do we see Ediacara fauna so quickly after such a dramatic epoch in Earth’s history?” The Ediacaran marks the rise of multicellularity with tissue specialization, although little fossil evidence exists concerning the precise nature of the Ediacaran biota. To study what conditions during the Cryogenian may have contributed to the resiliency of life during glacial periods, Summons and Evans both examine lipids, molecules that play roles in energy storage, biological signaling, and in fortifying cell membranes.
Evans specifically focused on intact polar lipids — known as IPLs — biomarkers diagnostic for living cells. “IPLs represent an important barrier by maintaining the flux and gradients of ions and nutrients between the inner cell and the environment,” Evans says.
“The analysis of IPLs provides the perfect tool to investigate how microbes can thrive under extreme climatic conditions, and how they adjust to the radical summer-winter environmental changes,” Evans says. Even further, the IPLs can help pinpoint important chemotaxonomic information about the cyanobacterial communities in the mats — which helps researchers like Jungblut determine the effects of climate change in the region over time.
To study the IPLs, Evans analyzed the compounds on an instrument that employs high-pressure liquid chromatography, coupled with a mass spectrometer. The instrument, which takes the space of a large closet, separates molecules based on their polarity and molecular formulae. From there, Evans deduces the lipid structures and abundances, and connects them with the environmental parameters of the particular microbial mats to determine what contributes most to the lipid variability within the different mat communities.
“Based on our data, environmental conditions, such the availability of nutrients and variations in temperature, seem to be the main driver of lipid membrane setup,” Evans says. “These microbes have a very special lipid signature that allows them to adapt to the extreme climatic conditions in Antaractica’s harsh environment.” In a continuation of this work, Summons and Evans are investigating other compound classes, such as the sterols that modulate the membrane behavior of the microscopic eukaryotes that occupy particular niches within an otherwise bacterially-dominated landscape.
“In the process of answering the most obvious questions others always crop up,” Summons says. “No matter what we learn, there are always curiosities that beg to be investigated.”
Continuing a legacy of Antarctic exploration syndicated from https://osmowaterfilters.blogspot.com/
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