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Humans Nearly Went Extinct 70,000 Years Ago
Josh Fink brings us a CNN story discussing evidence found by researchers which indicates that humans came close to extinction roughly 70,000 years ago. A similar study by Stanford scientists suggests that droughts reduced the population to as few as 2,000 humans, who were scattered in small, isolated groups. Quoting:
"'This study illustrates the extraordinary power of genetics to reveal insights into some of the key events in our species' history,' said Spencer Wells, National Geographic Society explorer in residence. 'Tiny bands of early humans, forced apart by harsh environmental conditions, coming back from the brink to reunite and populate the world. Truly an epic drama, written in our DNA.'"
This event probably ended up establishing the concept of "races", meaning small groups of geographically isolated humans ended up having a lot of genetically distinct features. As their populations grew, they seemed very foreign to each other and only in modern times those barriers to gene flow seem to be falling.
I look forward to the day when people stop saying "I'm X race" and instead say "I carry the genetic markers for A, B, and C." Well, perhaps it's unlikely, but an ex-biologist can dream, can't he?
Going back 70,000 years, then, there were only 2,000 of us...and...let's be honest...we were probably a skinny, not-too-bright, not-too-strong, disease-ridden, sorry-assed bunch of H. Sapiens. The Neanderthals obviously outnumbered us by many times over and could have rid the world of our kind. Thank you Neanderthals for sparing us...and we're sorry about anything we might have done to you...later.
The problem with global warming is three fold....
#1 it is unequally balanced..the temp changes more at the poles where the ecosystem is more sensitive to temperature. Therefore a small global change will mean dramatic changes in isolated areas.
#2 if you look through history, the average GLOBAL temperature over a one year period has typically hovered around 0 deg C for most of history. I hear that is an important temperature for something..... Anytime the temperature strays from freezing dramatic changes happen to the global environment.
#3 Consistency. So much of our modern society is based an the extremly mild conditions the earth has experienced over the last 20,000 years. Most of Europe is inhabitable ONLY because of the gulf stream and atlantic currents. Agriculture is ONLY possible because the temperature has been consistant year to year. We are in a sweet spot environmentally that is very unusual in earths history. screwing with the temperature is not going to help.
http://en.wikipedia.org/wiki/Toba_catastrophe_theory
Maybe it's because I pay attention to genetics and genealogy (and I thought people were geekier than I am here) but I clearly remember this news from 2006. Why is it getting recycled now, two years later?
Good old fashion starvation and disease. For reference, see the current food prices and how these are liked in the developing world. Biofuel mania has something to do with it, but increased consumption by people and animals people eat is the major problem.
Yes, it's entirely possible to get crop failures leading to starvation. But how many deaths? 1M? 10M? Not even a small dent in human population.
The flaw in your thinking is very common -- it assumes a static world that does not adjust. If people are dying by the millions, then things will adjust. Hunger is by far a distribution problem, not a food production problem.
Sometimes it's best to just let stupid people be stupid.
Volcanism. With global warming, the melting of the polar ice will result in a major redistribution of mass. The planet will want to conserve angular momentum. Something will have to give.
Huh? I suggest going to look up the mass of the earth, compared to the mass of all the water. The mass of ALL the water is proportionally tiny, much less the mass of just the ice. Then try and remember that the world goes through periodic ice ages that redistribute water mass all the time.
Sometimes it's best to just let stupid people be stupid.
This whole article seems to rest on the premise that humans left Africa en masse about 60,000 years ago. This is likely, but still a hotly contested theory. A rival theory contends that modern humans (Homo sapiens sapiens) originated about the same time from Homo erectus, whose bones have been found in Asia and Africa (the multiregional theory).
It stands to reason that the tests on mitochondrial DNA of a group in Africa is only useful if you assume everyone left Africa sometime after 60,000 years ago.
Given there are numerous sites in Australia that claim to have artefacts stretching back at least that far (and possibly 176,000 years ago) it is very likely there were pockets of humans in other parts of the world much earlier than 60,000 years.
This research actually only shows that there is evidence of a population crash in Africa. Not that homo sapiens across the world had a population crash.
If the pattern goes 9am, 10am, 11am, why isn't noon 12am?
...Could it have been a cataclysmic flood and not a drought?...
..through which the world that then was, being flooded by water, perished. 7 But the present heavens and the earth being kept in store by the same word, are being kept for fire until the day of judgment and destruction of ungodly men.
The same book where we may read about the (almost) extinction of humanity by water, informs us that the next time God will use fire!
2Peter 3:6
According to that book, Universe was stretched out (Big Bang) at the Beginning
Isaiah 45:12 I have made the earth, and created man on it; I with My hands have stretched out the heavens; and all their host have I commanded.
Isaiah 48:13 My hand also has laid the foundation of the earth, and My right hand has stretched out the heavens. I called; they stood up together.
And it will end up in "The Big Crunch" that follows "The Big Bang" that began it.
Isaiah 34:4 And all the host of the heavens shall be dissolved, and the heavens shall be rolled like a scroll; and all their host shall droop, as a leaf falls off from the vine, and as the falling from the fig tree.
2Peter 3:10 But the Day of the Lord will come like a thief. On that day the heavens will disappear with a roaring sound, the elements will be destroyed by fire, and the earth and everything done on it will be burnt.
Revelation 6:14 And the heaven departed like a scroll when it is rolled together. And every mountain and island were moved out of their places.
Now you don't HAVE to believe the things written in the Bible, but what if the above and everything else therein is true after all? Something to think about.
All theory is gray
Floods typically do follow droughts.. so I wouldn't be surprised if an oral tradition was formed around how the global flood (which is a legend in most every culture) was passed on for 70,000 years or so.
How we know is more important than what we know.
There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
the explosion of the Toba volcano, in Indonesia, that was believed to take humans to the brink of extinction:
Across the world the last eruption of a super volcano was the Toba volcano in Indonesia. This erupted around 75,000 years ago spewing out tremendous quantities of rock and ash and is thought to have reduced global temperatures by up to 21 degrees centigrade.
Answers: 1 - Geologic evidence. 2 - No. It tells us that the story's survival in ANY form after 65000 years of oral transmission defies probability? But we already knew that. 3 - None.
AFAIK things like ice cores can give us indirect (but very usable) evidence of temperatures for much longer time periods. Of course, with all the ice shelves/glaciers melting, that particular method might not be all that useful for much longer. However, I imagine that other geological methods can also give us indirect, usable evidence of climate over longer periods than, say, just using tree rings or the like.
Actually, there was a global flood 12000 years ago. The Laurentide Ice Sheet broke away and in the course of a few days the oceans rose over 100 feet.
Islands the size of those found in Indonesia disappeared in the Atlantic (the hoping points likely used by Clovis man to come to the Americas from Europe.) Entire groups of Flora and Fauna that lived on those Islands were wiped out as were any Human civilizations, unlikely to be found again due to their dept and location. The old coastal regions of the continents that were populated were wiped out as well. No wonder we have flood stories from all over the globe that are very similar.
There was a flood, but did God do it? no.
http://en.wikipedia.org/wiki/Silent_Spring How's this? Read the book for more.
Ponder that the gas, carbon dioxide, has light reflective properties that when amassed in the athmospere gets similar properties that of the glass in greenhouses. You don't deny the existance of greenhouses now do you?
If that is so, couldn't one set up a model of how an increase or decrease of that gas in the atmosphere would affect the temperature of the hypothetical scenario.
Indeed someone did, in the late 17:th century, Svante Arrhenius set up a model where he predicted that a doubling in the atmospheric carbon dioxide would increase average temperature by 4-6 degrees Celsius (IPCC puts this number closer to 2-4.5 degrees Celsius).
By measurement one has found todays carbon dioxide levels to be 35% higher than thoose of 1835, and the carbon in the new carbondioxide are consisting of isotopes which is consistant with the kind of isotopes it would be of if it came from the burning of fossil fuels (but not from natural sources).
So here I have the scientific method, and what do you have?
Your #1 is a downright lie, CO2 is a very potent very common greenhouse gas, a mere increase by 0.28 percentiles in the atmosphere would increase our global temperature by several degrees celsius.
#2 is a strawman, you only require a very small amount cyanide to kill you aswell, that doesn't mean cyanide is harmless.
#3/#4 are appeals to ignore the science for what feels right, nothing in thoose statements disprove global warming, even assuming their validity. Secondly, there have been no increase in solar activity, so why bring it up?
Global warming is very real and it was predicted more than a hundred years ago, yet now that it is happening, people are throwing their hands up and saying conspiracy/hoax/coincidence. Global warming is very real, and it will cost the society alot of money, wheter you beleive in it or not.
I used to get a very honest and insightful ecology magazine called "Garbage" edited by Patricia Poore. It did well for a year or so, then started getting angry letter campaign and boycotts because they didn't follow the party line on various issues. For instance, they actually did a life cycle analysis of disposable vs cloth diapers, and found that life cycle costs were less for cloth in areas with hydro power (New England) and plentiful water, less for disposable in arid areas (Arizona, California), and about the same everywhere else. That didn't sit well.
As for diseases, there is no earthly disease that kills 100% of its victims, (because such a disease would then itself become extinct).
HIV/AIDS. If the time between infection and death is long enough, a disease CAN kill 100% of its victims, finally dying with its last victim, no?
...vast majority of scientists agree...
And since when has the vast majority of scientists or even people in general been right? Truth is an independent variable. It has no relationship to how many believe or disbelieve a given theory.
The number of things that the majority of people, even scientists, have believed throughout history, that were dismally and totally wrong can fill books.
Need evidence? Take a look at the relatively recent history of the "science" of climate change and the media hype surrounding it:
In the Feb. 24, 1895 issue of the NY times the headline was: "GEOLOGISTS THINK THAT THE WORLD MAY BE FROZEN UP AGAIN". The same paper on May 15, 1932 headlined: "EARTH IS STEADILY GROWING WARMER". Again on May 21, 1975, in the Times, "MAJOR COOLING IS WIDELY CONSIDERED INEVITABLE" and also on the cover of TIME magazine of Dec 3, 1973, "THE BIG FREEZE". Finally recently, again on the front of TIME, April 3, 2006, "SPECIAL REPORT ON GLOBAL WARMING
Scientists today have fancier computer models and a little better data gathering capability than back in 1895, but are likely just as wrong as their ancestor scientists were over time. Those guys back then just as sincerely thought THEY were right as today's chicken little "scientists" think they must warn us that the temperature sky is REALLY going to fall THIS time.
So if you believe them, get out of your SUV now and WALK! If the gasoline prices keep going up at the pace they have recently, that problem will be solved, since everybody will be walking, or at least riding a bicycle.
All theory is gray
If you don't like Genesis, there is a Hungarian Myth that tells the story of the Huns (one of the language groups) beginning with the tower of Babel (the Genesis story above). The best telling, IMO, is The White Stag, by Kate Seredy.
I'm giving up modding to point this out, but perhaps you might want to consider that many systems in nature tend to be a kind of check-and-balance. There are effects in the system which dampen the issue, things which remove carbon from the air and bind it. If we continue to increase the CO2 levels, we will overwhelm those checks and then all hell will break loose.*
/rant
The other thing I'd like to mention is that there really are more things to consider than just CO2 levels in terms of global warming. I don't think that human carbon dioxide emissions will be the end of us, but it could trigger the chain of events that leaves our planet much less hospitable to us. Have you heard of the methane hydrates in the cold sea bed?** It's possible that a small shift caused by our increasing carbon dioxide emissions - even if they have to increase by another 30% or maybe more - will push the temperature over a critical threshold and trigger a cascade which will again cause all hell to break loose.
So in a way, you are right. Except in climates which are around a sensitive temperature (e.g. Those areas where the temperature hovers near 0 degrees C) there is very little change right now. That could be that CO2 emissions are having a very minimal effect on the temperature, or more likely IMO, that's just that we haven't quite overwhelmed the checks that are in place.
* (IANA Environmental Scientist, so there may be a margin of error in the direness of my predictions)
** http://dsc.discovery.com/news/2008/02/26/methane-global-warming.html
What I'm saying is: if we're already half way there, where are the effects we should be seeing today? Where are the droughts and famines and floods that everyone is talking about? Is there some reason to believe that there's a threshold value, and once we cross it the problems will begin. It seems to me that if the CO2 if trapping heat, we should see the temperature rise with CO2. That would mean that we can expect another 1/2 degree rise at the most in the next 50 years.
How do you think scientists got that information on the length of ice ages, but can't get a decent grasp on average temperature for more than 2000 years? Your sentences directly contradict each other.
Slashdot needs a "-1, Wrong" moderation option.
The Urban Hippie
http://www.rollingstone.com/news/story/12343892/can_dr_evil_save_the_world/print A real-life experiment in the Arctic was, of course, out of the question. But after some discussion, Caldeira and Wood decided to run some computer modeling to see if shooting particles into the stratosphere over the North Pole could help stabilize the region. How much sunlight, they wondered, would you have to reflect to stop the ice from melting? What effect would it have on the rest of the Earth's climate?
Scientists routinely use such computer models to test the effects of various climate-related scenarios, from rising CO2 levels to the impact of deforestation on global warming. After several weeks of running a climate simulation on Stanford's superfast computer network, Caldeira concluded that shading the sunlight directly over the polar ice cap by less than twenty-five percent would maintain the "natural" level of ice in the Arctic, even with a doubling of atmospheric CO2 levels. Push the shading up to fifty percent, and the ice grows. Even better, the restoration happens fast: Within five years, the temperature would drop by almost two degrees. 2 degrees Centigrade is a lot in global warming terms. Wikipedia says "The average global air temperature near the Earth's surface increased 0.74 ± 0.18 degrees C (1.33 ± 0.32 degrees F) during the hundred years ending in 2005". The modeling results interested Wood. He calculated that it would take roughly 300,000 metric tons of particles each year to shade the sunlight in the Arctic by twenty-five percent -- a tiny amount, on a planetary scale. As for how to get those particles up there, Wood thinks that a half-dozen 747s could do the job. Even better, you could build a Kevlar tube fifteen miles long, with a diameter slightly larger than a garden hose. The bottom of the hose would be connected to a combustor that created the aerosols, while the top would be held in place by high-tech kites or a high-altitude airship that the Defense Department is developing. "It's nothing more than a fancy blimp," Wood says.
In Wood's view, this was a no-brainer. You could stabilize the ice, save the polar bears and demonstrate the virtues of planetary engineering for less money than it takes to feed and clothe the soldiers in Iraq for a year. Because the aerosols are launched only over the Arctic, there is little danger of directly impacting humans. And best of all, you can try it for a few years and see if it works. If something goes wrong, you can quit, and within a year or so, all the particles will have dissipated, returning the region to its "natural" state. I like this quote too. "Human beings are like cockroaches," Wood says with typical black humor. "It's fairly easy to kill the first ten percent of the population. And if you try really hard, you might even get the next ten percent. But no matter what you do, you'll never get that last ten percent. We will find a way to survive." That's the spirit.
echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
Isn't this genetic bottleneck already credited to the Mt Toba explosion (Indonesia) which happened about 70,000 years ago?
The Mt Toba explosion is believed to have been so huge (vastly larger than Krakatoa) that it plunged the whole earth into a "nuclear winter"-like period (just look up "Mount Toba" or "Toba catastrophe theory" in Wikipedia).
In any event, we already knew that there was a genetic bottleneck about 70,000 years ago, as those Wikipedia articles indicate. What's the real genetics news here?
I am anarch of all I survey.
In addition, there are several thousand years worth of recorded events before that, but by historians living long after (although still ancient by our perspective) they supposedly occured. Many such cases can be considered the "historical" myths of their time, although in other cases historians mention the titles of prior works now unknown to us (thus indicating that these were written, rather than oral, legends).
See there's my problem with global warming....Ask most geologists if climate change is occurring, and they will tell you that climate is never constant.
If we are changing the climate, many species may die out but many will survive. However, from a human standpoint, we may be in for a lot of headaches as people have to adjust to conditions they and their dwellings are not used to. People may have to abandon entire countries as they turn into desert. It will be very unpleasant to us, not just the animals. It will make conservation look cheap in comparison.
Table-ized A.I.
I have. I talked to a lot of them when I was getting my geology degree in college. You're right that the climate is constantly changing. You're wrong if you think that implies that humans cannot change the climate.
You're also wrong if you think that recorded human history is the only record of past climate that we can reference. There are numerous natural records of past climate that go back much further into the past. And by the way, the best estimate for an average global surface temp is actually about 14 degrees C, not 0. I have no idea where the grandparent got that number. Maybe they mistook temp anamoly for absolute temp.
Finally, it may surprise you to learn that many researchers of past and current climate do in fact hold geology degrees.
Build a man a fire, he's warm for one night. Set him on fire, and he's warm for the rest of his life.
Depends how you define significant, of course, but the consequences of running out of oil...
We will NEVER "run out" of oil. It doesn't work like that. It just gets more and more expensive to pull out of the ground. When cheap fossil fuel gets more expensive than the alternatives, then we'll switch to the alternatives (of which there are many).
Sometimes it's best to just let stupid people be stupid.
What ever you say, big guy.
Let me know when Darfur gets down to 2000 people.
You will still be WRONG, by, say, the rest of the known world, but just to make it easy on you, I'll confine the argument to Darfur. The area will NEVER again see a population of less than 2000 individuals.
Sig Battery depleted. Reverting to safe mode.
The more we learn about ourselves and our planet, the more Dawkins is right: What really happened is just so much more interesting and fantastic than the fiction our ancestors put into their holy books.
This (hi-)story definitely beats the whole "flood and Noah's Ark" bullshit. Evolution is a lot more thrilling than creation. And quite frankly, being distantly related to the other animals creates a lot more emotional connection than being told "here, rule over them" by a fictional daddy-of-all.
Not to mention that even a short look into outer space beats the entire bible in amazement.
We need more science like this, and less funding for the outdated liars.
Assorted stuff I do sometimes: Lemuria.org
Funny though,IIRC the worst polluter we have for greenhouse gasses ISN'T cars and factories,as one would guess,but instead it is the methane created by the millions of cows we have bred farting their little brains out all over the planet. Apparently their natural diet makes for seriously gassy cows whose farts are almost pure methane. There has even been talk of trying to alter them genetically so as to make them not as flatulent. Too bad there isn't an easy way to capture all that methane. Talk about a quick fix to the rising costs of fuel. We could just run everything on cow farts!
ACs don't waste your time replying, your posts are never seen by me.
Actually it reminds me a lot more of the noah's ark myth/legend/passed-down-and-mutilated-account.
Is it such a big stretch to imagine such a tough time in history being passed on through stories until it ended up in one of the main spiritual books around today?
3) What remnants of an Ark would one expect to find 70000, or even 5000 years after the fact? Conversely, what evidence could be shown that would decisively PROVE OR DISPROVE that the event happened? And I'm talking about scientific evidence here. Not anecdotal faith-based cruft. Not even science-based faith-based cruft, if you please...
I thought the Noah legend was just that the Jews borrowed a preexisting actual story and adding in some morality to the story so there would be point in telling it. If I recall correctly, the current theory was that there was a guy that had a grain ship that he lived on with all his various livestock. Big flash flood/storm happened and washed them out to see. Big storm several days and when storm cleared/moved on. They were in the middle of the sea. What's the answer to where the land went? The entire earth must have flooded. O.k. the guy had a big ship so his concept of the entire earth was where he sailed his craft and who he normally traded with. Obviously, the guy made land fall traded with the natives and became local rich guy. Guy shows up with huge ship with grain/animals of course he is rich in the ancient sense. The guy lives somewhat happily ever after. The world hardly noticed that it was supposedly ended during a storm. Of course "the world" for the villages that the guy normally traded with where ended, but that was due to the damn river flooding and a storm. Oh, yeah the local survivors can blame it on the local deity being mad at them.
http://en.wikipedia.org/wiki/Deluge_(mythology)
Remember POV in these stories is everything. "The World" as the town/village and everything that you are normally exposed to has ended millions of time in our history. It s just now that alot of people are actually being exposed to the concept of the actual entire world rather than the tiny portion of it that they live on be ravaged by war or something that we now have to worry about it. We love to expand what we worry about. 200 years ago we didn't worry about gaint rocks falling from the sky killing everyone.
Live today, because you never know what tomorrow brings