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Dinosaur-Killing Asteroid Could Have Caused 2 Years of Darkness
- QAPereo 9y agoNaively I would assume that if we really had experienced two years of darkness, avian species would not be here now.
- ljf 9y agoWould be interested to hear your thoughts that led you that way (not saying wrong or right, just interested)
- cwbrandsma 9y agoFeathers act as insulation, they are warm blooded, and opportunistic eater. My chickens are hardy to -20 degrees outside. So long as they were farther south I could imagine them surviving. Even if they were north, as long as they could eat meat, the coming cold temperatures could keep food (other dead animal) around for quite a while. Even then, I could image ancestors of vultures doing quite well for a good long while. Anyway, also a naive set of guesses on my part.
- blacksmith_tb 9y agoI do have to wonder how plants could have rebounded from two years without being able to photosynthesize - you'd think lots of species wouldn't have viable seeds kicking around at that point. Which would make for some massive changes to the fossil record for plants. To say nothing of the animals that depend on them...
- retSava 9y ago66 mn years is plenty of time to diversify a lot from a few, so you might be correct that "lots of species wouldn't have viable seeds". Perhaps they didn't, and just the (relative) few that did are the basis of what we have today.
- colordrops 9y agoLots of seeds remain viable for more than 2 years.
- QAPereo 9y agoIt would also have to remain viable in the sense that no animals starving in the darkness will try to eatthem, or fungus or bacteria running wild. I think you have to assume that are small burrowing ancestors ate pretty much every seed they could get their tiny paws on. We know that quite a few different organisms survived, and while some of them estivated or hibernated most of them presumably we had to live and eat in a roughly normal way.
- colordrops 9y agoSure but there's no way they'd find every single seed on earth.
- rangibaby 9y agoFungi and bacteria don't like the cold. There would be a lot more food to eat for survivors (chickens) as things that they competed with for food (T rex) died off.
- mixmastamyk 9y agoOwls and kiwis prefer the dark.
- QAPereo 9y agoDo their food sources?
- Gingeas 9y agoInteresting point - even though some animals might thrive in the dark, the food chain can also be undermined in a way that it topples the foundation of the members above, thus indirectly destroying it. Owls consume rodents such as squirrels, rats, and mice, which are nocturnal. Kiwis eat grubs and worms - only the latter of which I know can be nocturnal.
- rangibaby 9y agoKiwi's long beak is for scooping things out of the ground. I think it is pretty dark down there.
- roceasta 9y agoI think our present space technology research focus should be on these asteroids. Both how to deflect them (peacefully) and how to mine them for rare metals. If I read this table correctly it seems that only eight days ago a fairly chunky rock passed within 60,000 miles of us: https://cneos.jpl.nasa.gov/ca/ https://cneos.jpl.nasa.gov/ca/
- retSava 9y agoWell, in >4 bn years there have been probably less than 5 such events. Catastrophic yes, but very low possibility. I can understand if any agency even the slightest related to space prioritizes other things. As far as my understanding goes, space is very unevenly distributed, with lots of debris and asteroids in dense (well, humpf) parts of space, but the vast majority of it is just... empty space with so little matter in between that it is basically negligible. To mine an asteroid likely means going to where it's more probable to find a suitable one, and also more risky. Asteroids around us are few (IIUC).
- sqeaky 9y agoDeath by asteroids is a low risk but high impact type of event. We cannot afford to have even one such event. It really does only take one and costs little for us to prepare. We want to mine asteroids and further science anyway, so we are going up there already. It's not like the cost of the whole space program is dedicated to defending from this. We just need to have a few plans ready to go when we do find it. It would cost millions of dollars, compared to the billions already in space and trillions we spend in defense. What is money in the face of a 0.00001% chance of annihilation? EDIT - Wording and spelling.
- coldtea 9y ago>Death by asteroids is a low risk but high impact type of event. We cannot afford to have even one such event. Depending on how rare and difficult to tackle would be, we probably also cannot afford to do anything about it. If we have as much as 1% or even 0.1% possibility of one hitting earth in the next 100 years, we would have rallied to build something even if is very costly and difficult. In 0.00001% chances or less, there's no way any country is gonna's devote any significant resources... >What is money in the face of a 0.00001% chance of annihilation? Still very important? (We have a much more concrete and possible chance of billions of deaths from nuclear arms and/or global warming, but we still don't do anything about it).
- brianbreslin 9y agoThis may be a dumb question, but were all the dinosaurs reptilian and avian? Were there no mammalian dinosaurs pre-66M years ago? like rodents?
- rarec 9y agoThere were proto-mammals then, similar to possums. https://www.thoughtco.com/the-first-mammals-1093311 https://www.thoughtco.com/the-first-mammals-1093311
- kobeya 9y agoDinosaur is a specific class of animal. Theee were rodents back then, which we evolved from, but they weren't dinosaurs.
- thanksforcoming 9y agoDisclaimer: this is proving hard from me to explain via text without the use of visualization. Mammals did not evolve from dinosaurs. Mammals are synapsids, a branch of tetrapods. Dinosaurs come from a different branch of tetrapods entirely, called sauropsids. (There is a third branch of tetrapods, amphibia.) Sauropsida is a really diverse branch containing both extinct and extant species. Look at the tree at the bottom of the page here [0]. A fork of interest is Sauria, which splits into lepidosauromorphs (including modern lizards & snakes) and archosauromorphs. Archosauromorphs have many branches as well (one of note being turtles), with one that traces far enough to get to archosaurs [1]. Modern crocodiles come from a branch of archosaurs. Dinosauria are another branch of archosaurs, and birds are descendants of dinosauria. They are the only extant species of dinosauria. The confusion comes because many of these animals co-existed at the same time, some become extinct, others evolved and change and form new branches (but still belong to the parent group). The word 'Dinosaur' itself is also misapplied by the public - it's not all of the animals that lived 65+ million years ago. It's a very specific group of related animals and all of their descendants. TLDR: Mammals didn't evolve from dinosaurs, but from a different branch further up the chain that dinosaurs also belong to. Those mammalian ancestors did co-exist with dinosaurs. Like mammals, modern reptiles didn't evolve from dinosaurs, but from ancestors that co-existed with dinosaurs. Reptiles and dinosaurs are more closely related than mammals and dinosaurs. Birds did evolve from dinosaurs, and are the only living dinosaurs today. [0] https://en.wikipedia.org/wiki/Sauropsida https://en.wikipedia.org/wiki/Sauropsida [1] https://en.wikipedia.org/wiki/Archosaur https://en.wikipedia.org/wiki/Archosaur
- julienchastang 9y ago"A world without photosynthesis", "photosynthesis would still have been impossible for an entire year" Clearly, photosynthesis did survive in some capacity. No? Life did not re-evolve photosynthesis in the last 66 million years.
- Xeoncross 9y agoSeeds can germinate after much longer than a year: https://en.wikipedia.org/wiki/Oldest_viable_seed https://en.wikipedia.org/wiki/Oldest_viable_seed
- blacksmith_tb 9y ago"Some seeds can live for a long time before germination, while others can only survive for a short period after dispersal before they die."[1] I wasn't suggesting all seeds would fail to germinate after two years, just that some would, and that change would be noticeable in the fossil record. 1: https://en.wikipedia.org/wiki/Seed#Germination https://en.wikipedia.org/wiki/Seed#Germination
- Xeoncross 9y agoOld seeds had much higher germination rate according to the linked wikipedia article. In addition, cold storage increases the life of seeds. I doubt you would see much of anything in the fossil record.
- dasil003 9y agoAll photosynthesizing plants could die and then re-sprout from seeds without extinction.
- pilom 9y agoSeeds can remain viable for significantly longer than a year. My guess is that as it got significantly colder for that same time period, most seeds were too cold to grow until it warmed up after the soot left the atmosphere.
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- excalibur 9y ago> While the scientists think the new study gives a robust picture of how large injections of soot into the atmosphere can affect the climate, they also caution that the study has limitations. > For example, the simulations were run in a model of modern-day Earth, not a model representing what Earth looked like during the Cretaceous Period, when the continents were in slightly different locations. The atmosphere 66 million years ago also contained somewhat different concentrations of gases, including higher levels of carbon dioxide. > Additionally, the simulations did not try to account for volcanic eruptions or sulfur released from the Earth's crust at the site of the asteroid impact, which would have resulted in an increase in light-reflecting sulfate aerosols in the atmosphere. Additionally, the "world-class computer model" in which the simulations were run may or may not have been a Minecraft server.
- sogen 9y agoHow can they publish something so wrong? Also: Get off my server
- SapphireSun 9y agoBefore decrying how wrong it is, try estimating how much those effects matter.
- mrfusion 9y agoI'd be curious how any animals survived.
- frandroid 9y agoAlso: Soul-killing Election Causes 4 Years of Dankness.
- 09bjb 9y agoGraham Hancock dedicates at least 10% of his most recent book "Fingerprints of the Gods" to exploring the recent evidence for a cataclysmic meteor impact that catalyzed the precipitous drop in global temperatures we observe 12900 years ago at the "Younger Dryas Boundary." https://en.wikipedia.org/wiki/Younger_Dryas#Impact_hypothesis https://en.wikipedia.org/wiki/Younger_Dryas#Impact_hypothesi... He has some pretty out there theories but that section is pretty convincing.
- Retric 9y agoMy understanding is the duration does not really line up with an impact event also the starting periods don't seem to line up correctly. "In Western Europe and Greenland, the Younger Dryas is a well-defined synchronous cool period.[34] Cooling in the tropical North Atlantic may, however, have preceded it by a few hundred years; South America shows a less well-defined initiation but a sharp termination." Which is what I find annoying about pet theories in books, you can make plenty of things seem convincing by leaving out other evidence.
- Pica_soO 9y agoFascinating is the feedback loop recovering after the impact. So basically, all that is needed to bring the sood from the atmosphere down is a long enough cooling window, binding ice to the dirt.