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Jan
Mountain climber
Colorado, Nepal & Okinawa
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Very interesting. However, further on they state,
'There is no proof in the paper that the origin of the [DNA] is Denisovan." He says it could just as easily have come from Neanderthals, whose EPAS1 looks similar to the Tibetans'. That might make more sense as they were common on mainland Asia, whereas the Denisovan heartland seems to have been in South-East Asia.
Whichever it turns out to be will prove very interesting as the Chinese do not have the same adaptation to altitude as the Tibetans.
Students of East Asia have long tried to sort out Chinese uniqueness myths from fact. The Chinese insist they originated in the north but there is considerable evidence that most of the original inhabitants came from the south, and northerners only later. Then there's the fact that Chinese fossils of 100 to 300,000 years ago have unique features not shared by any others in the world leading them to claim a separate and unique evolution, a claim which the DNA evidence denies, showing that everyone of them is descended from people who left Africa.There are also people in both Japan and Tibet whose DNA is similar to each other but different from Chinese or other north Asians, being most closely related to the dark skinned indigenes of the Andaman Islands in the Indian Ocean, obviously a very ancient migration.
There is also some evidence now that the Sherpas were living in the area of Mongolia, before migrating to eastern Tibet and then westward to Nepal. All of these complicated DNA distributions would indicate that Chinese and Tibetans have different origens, one from Denisovan and one from Neanderthal. This is definitely politically incorrect as far as the Chinese are concerned but very interesting to the rest of us.
I'm betting that the majority of Chinese came from Denisovan and Sherpas and Tibetans from Neanderthals.
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cintune
climber
The Utility Muffin Research Kitchen
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Dammnit FM, putting words in my head again.
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Jan
Mountain climber
Colorado, Nepal & Okinawa
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I think the impression that there are not many homonid fossils from East Asia is the result of Chinese paleontology not being well known outside of China and also because the Chinese paleontologists keep insisting that their specimens are unique and not related to other humans on the planet, an idea definitely out of favor in the rest of the scientific world. At the 16th conference of the International Union of Anthroplogical and Ethnological Sciences (IUAES) held 2009 in Kunming, China, I attended a lecture in which we watched slides of Chinese fossils from different sites for a full hour. And sure enough, they all had obviously different characteristics than others in the world.
At the same time, the younger DNA specialists trained in the West were equally clear that out of hundreds of thousands of DNA samples of living Chinese, all came out of Africa. As one of them put it, "I know I have ancestors. The proof is in my DNA. A paleontologist can only hope that his fossils had descendants". When Denisovan was discovereed, I immediately thought that the way to reconcile the two different sets of data, must lie with this previously unknown species of human. Now the data from Tibetan adaptation to altitude seems to indicate the same.
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Ward Trotter
Trad climber
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All of these complicated DNA distributions would indicate that Chinese and Tibetans have different origens, one from Denisovan and one from Neanderthal.
Are you saying here Jan, that the Han and Tibetans have primarily differing origins, namely , one derived from Neanderthal and the other from Denisovan?
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Jan
Mountain climber
Colorado, Nepal & Okinawa
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That's sure what it looks like, which is puzzeling because they are in the same language family but the DNA even in China, is more complex.What has been found in northern China is that both males and females came from the north. South of the Yangtze, the females are from the south and the males from the north. Many tribes that used to live south of the Yangtze now reside in Indonesia.Obviously there have been some major migrations in the past and the northern people came to dominate along with their language. The question is who the earliest people were who moved into both China and Tibet from the south and whether they were related to Neanderthal or Denisova.
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Ward Trotter
Trad climber
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Yes, it's all rather confusing.
I have detected several theories as regards the origin of the Tibetans and the likely origin of their high-altitude gene expression.These are not necessarily distinct competing theories but perhaps make up the central elements of larger emerging ideas.
1) Tibetans were originally Han who migrated into the Plateau as late as 3-6 thousand years ago. At least 9% (more or less) of this ancestral Chinese population(as they do today) had the EPAS gene variant from earlier absorption of Denisovans. Once in the higher altitudes the EPAS gene turned on by adaptive mechanisms and thus became a selection template resulting in Tibetans capacity to thrive in that environment.
2) Tibetans were Han who encountered ancestral Nepalese Sherpas in the high country (possibly as long ago as 30,ooo years) and through admixture acquired the EPGN1 and the EPAS1 variants. These early Tibetan populations would also have been carrying the roughly 9% Han EPAS1 compliment from earlier contact with Denisovans .
Both Sherpa and Han acquired these genes from a Denisovan source; either solely Denisovan, or from as yet additional undiscovered sources.
The researchers found that, on a genomic level, modern Tibetans appear to descend from populations related to modern Sherpa and Han Chinese. Tibetans carry a roughly even mixture of two ancestral genomes: one a high-altitude component shared with Sherpa and the other a low-altitude component shared with lowlander East Asians. The low-altitude component is found at low to nonexistent frequencies in modern Sherpa, and the high-altitude component is uncommon in lowlanders. This strongly suggested that the ancestor populations of Tibetans interbred and exchanged genes, a process known as genetic admixture.
http://www.sciencedaily.com/releases/2014/02/140210082912.htm
Additionally:
The team also found that Tibetans shared specific high-altitude component traits with Sherpa, such as the EGLN1 and EPAS1 gene variants, despite the significant amount of genome contribution from lowland East Asians. Further analysis revealed these adaptations were disproportionally enhanced in frequency in Tibetans after admixture, strong evidence of natural selection at play. This stands in contrast to existing models that propose selection works through new advantageous mutations or on existing variants becoming beneficial in a new environment.
The recent Denisovan revelations seem to be in the category of perhaps suggesting the provisional reinforcement of "existing models"
...existing variants becoming beneficial in a new environment
In other words, maybe the ancestral Han populations, by way of the Denisovan EPAS1 variant, played a detectable role in the Tibetan adaption to higher climes---not strictly admixture with Sherpas.
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Bushman
Social climber
Elk Grove, CA
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'The Universal Dial Tone'
The Universe called me on my phone the other night and said, "Aside from the fact you haven't called me for awhile, how are things?" I said the usual stuff about work, marriage, health, etc. Then it asks me, “At what point do you intend to leave the comfort of your home and begin exploring my vast and almost infinite space?" I replied with the usual excuses like I can't find anyone interested in going exploring with me, my finances are kind of tied up right now, and it's really hard to get motivated after coming home from work in the evening.
The Universe said, "You must think five billion years is a long, long time, well it's not! You probably believe you have all the time in the world to solve planetary strife, colonize mars, find a habitable world in a different solar system, and develop light speed star ships to take you there before the sun puffs up into an orange giant, vaporizes the planets, and then blows itself apart! Five billion years goes by in the blink of an eye!" Feeling rather taken aback I replied,” If you're just calling to nag at me again, this conversation is over." In a more conciliatory tone the Universe said, "Now, now, calm down. I just need you to know how imperative it is that you try to come out and see me, to really allow myself to experience myself through you, my child. You see I've waited a long time for you to evolve, and to become self aware, and to become technologically advanced. And while hoping to see you throw off the trappings of superstition, class warfare, and other social ills, I have forgotten how frail and timid you all are. I have also overlooked the fact that most humans think of themselves as individuals, alone and isolated from the rest of life on earth or possibly, of life on other worlds. How sad that so many of you are intimidated by contact with others, are fearful of embracing each other for the common good and working together to discover and unlock the many wonders and secrets of my frontiers."
It was quiet for a bit and I responded, "I really have tried to talk to people about our obligation to put aside our petty squabbles, about accepting the consequences of our impact upon the earth, and about embarking on a mission of scientific discovery and space exploration that we all could take part in on some level. Often, when I bring up this topic, people lose interest or are preoccupied by other interests or subjects of conversation such as sports, fashion, or politics. It's exasperating to see people act as if they have no interest in the generations of human beings to come, as if they have no relation whatsoever to their descendants. I've seen how some species eat their young and am frustrated to think that as advanced as people think they are today, they have chosen to cannibalize on the resources and materials necessary to build on the hopes and dreams of tomorrow's youth. Still, I try to remain vigilant, reminding young people on a daily basis of the need to be educated and find careers in the fields of science, math, and technology."
After a long pause I wondered if the Universe was still listening. "Hello?" I asked quietly. I heard a click, and then shortly thereafter was the continuous monotonous buzzing of a dial tone.
-bushman
02/11/2014
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PSP also PP
Trad climber
Berkeley
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JG said "OK, so you are not suspending the "I" while in the "no-thingness" meditative mode necessarily, but in daily life as well. Does "no-thingness" also appear in normal circumstances? "
"no - thingness" is mind not attached to thinking. So it is always there . Attachment to thinking obscures it so you can't observe/experience it. You don't create no-thingness with meditation it is always there. another name for no-thingness is interconnectedness or non-separation.
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MikeL
Trad climber
SANTA CLARA, CA
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Bushman:
That got a smile out of me. Thanks. I wonder how people read the third paragraph. If they read it closely, did they see it as an honest expression of a warm-hearted humanist who laments the scarcity of resources and a general lack of goodwill in the world--and hence as a description of what's the true state of the world? Did anyone read it ironically--that is, as a typical view of "what is?" (Indeed, isn't that why the universe hung up? The author isn't seeing things as they are.)
There's nothing good and nothing bad in reality. Everything is just perfect. Mistakes and wrongness are just not possible. Not Hitler, not Mother Theresa, not me, not you. Digging down by employing a little peace and quiet and stillness can begin to show that to anyone. Meditation will do.
"No-thingness" is simply a term that's meant to point to something that cannot be said. Actually, no thing can be said because there is no thing other than Reality (this THIS right here right now beyond all the supposed things there are). Reality cannot be described, even though it can be known.
I don't mean to put a damper on the fun, but all these efforts are fruitless--until you see that they are fruitless . . . then seeing can begin.
I'm moving to Seattle in a few days, and so I my wife and I went up and had lunch with my teacher. My wife had many questions for him. I had only one. What am I supposed to make or do when I see everything around me as an absurdity? (Doesn't happen all the time, but increasingly so.) He told me: "this is where you're at right now. Don't worry, it will resolve itself. Nothing can be wrong. It's not possible." All I can say is that I'm here to fulfill whatever role that I find myself in, just be who I cannot help but be . . . and to watch that happen and me unfold. It's all that's ever happening, you know?
(Thanks, Bushman. Your post was kinda fun.)
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MH2
climber
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Cheers, MikeL. Come visit Squamish if you get a chance. We are as fruitless as they come.
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jstan
climber
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https://www.youtube.com/watch?v=nNcVtRLyiCU
Frank Wilczek on mind and matter.
What is this presentation? It is a celebration of what can be done when one allows one's mind to
observe and ask questions about what is around us. Matter. It starts with a discussion of how we
can realize Pythagoras' Theorem and how that signal event introduced us to geometry. An
incredible game which has yet to finish instructing us. The talk starts where we arguably first
came to understand the power within us and it then sweeps across many of the adventures of the
mind we have engaged in over the intervening centuries. Boldly and with the whimsy for which
this speaker is so renowned.
The net effect is not that of convincing us this speaker has the power possessed by a Caterpillar
D8. Indeed its clearly intended effect is to persuade us we have that power.
The talk is a trip.
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MikeL
Trad climber
SANTA CLARA, CA
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At 1:16:05, Wilczek says, "There are no real neurons. It's a mathematical construction."
Real science = Real Reality?
Hardly.
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MikeL
Trad climber
SANTA CLARA, CA
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P.S. A little bit of critical thinking could be useful now and then. Professor Wilczek speculates about mind, the brain, and meditation when he appears to know nothing about any of them authoritatively. Perusing his publication list will expose no publications in any cognitive science, meditative, or neuroscience journal or review. It's a bit remarkable that he made his presentation about mind at all. He's obviously well-qualified to talk about matter . . . but mind? Sure he has one but has he been making careful observations?
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Ed Hartouni
Trad climber
Livermore, CA
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the sine qua non of "authority" in science is the consistency of hypothesis with observation, not the personal bona fides of the persons making the hypothesis or the observations.
bona fides are useful where they indicate a mastery of the subject matter, presumably avoiding already tested hypotheses. (It is often quite useful to repeat observations, especially when improving them, though in general it doesn't make too much sense to repeat a measurement unless you can do it at a level that challenges the hypothesis, unless one is confirming another observation).
So while Wilczek may not be published there are certainly physical constraints that are relevant to the discussion, of which he is certainly "qualified" to make. I haven't watched the video so I don't know what was said, specifically. Physicists do a sort of estimating as an exercise, trying to suss out the essentials of a question.
For instance, we could calculate the energy required to create "mind" as a computation and see if the amount of energy required to execute the computation is consistent with the observed energy use of the brain. This would require some hypothesis on what that computation is and how it is performed.
In some ways we've already done this, take IBM's Watson, and say it has succeeded in the computation of "natural language" recognition. Watson is composed of ninety IBM Power 750 servers... oddly I can't find the power spec, but some literature seems to indicate that there are servers with 550 W and 750 W power supplies... for our "physicist" estimate let's take 0.5 kW per server, 90 servers represents 45 kW of power for Watson...
the brain uses about 12.6 W of power, which is 4000 times less energy, and accomplishes at least as much as Watson does (the brain is capable of more than just "natural language" recognition).
So we can conclude that the brain doesn't compute the "natural language" recognition the same way that Watson does... and that's an important conclusion, but more importantly, it provides a quantitative indication of the efficiencies of the brain computational architecture compared with our current computer/AI architectures.
This conclusion is not surprising in a qualitative sense, but it provides a challenge to the hypothesis that the brain produces "mind" as a sort of computation (using "sort of" honors our lack of understanding of that, exactly "computation" means in this context).
Were I to watch the video, I'd be looking for the same sort of arguments... or speculations that could be turned into hypotheses which could be tested. I wouldn't be worried so much with Wilczek's CV.
But that's just me...
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cintune
climber
The Utility Muffin Research Kitchen
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Well, this might bolster Largo's contention that we're all just absolutely terrified of simply sitting quietly:
http://www.newscientist.com/article/dn25849-idle-minds-succumb-to-temptation-of-electric-shocks.html
"I believe that the mammalian brain evolved to engage with the world – looking for opportunities, avoiding dangers, and solving problems. Human beings, as far as we know, are the only species who are also able to turn their attention away from the external world and just think for extended periods of time, but the fact that the mind evolved to engage with the world may place limits on our ability to do this."
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Ward Trotter
Trad climber
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The above quote is a point I have made numerous times in discussions on this thread when I have averred that our brains are evolutionarily calibrated to the external world of tooth and claw.
I think once or twice I was consequently accused of practicing a reductionist determinism based upon evolutionary biology.
In order to , as it were, more or less successfully short circuit this calibration (e.g. with meditation), apparently requires years of devoted energy and focus---a point also made ad nauseum on this thread.
Hence my outlandish claim that acolytes can --via Biohacking-- reduce this entire process down to 4 or 5 days.. . Minimum...LOL
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Jan
Mountain climber
Colorado, Nepal & Okinawa
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I was once startled while reading Kalu Rinpoche, considered one of the most evolved Tibetan reincarnates, when he noted, "Meditation goes against evolution". "Oh, no not you too", I thought."And why you, when I've never heard that sentiment from any other Buddhist?". Then as I continued on, he noted, "evolution is about survival at all costs. Meditation is about going against those selfish impulses and becoming a compasionate being instead". At this point it occurred to me that meditation is a kind of luxury for people with a food surplus and leisure, and an environment that is peaceful. Evolutionary anomaly or a glimpse of a better future? Take your pick.
Meanwhile, thanks so much Ward for bringing those articles to my attention. Those are the most interesting new pieces of information I've wrestled with since Cynthia Beall, one of the co authors, and I spent the summer of 2011 corresponding by email, trying to corelate patterns of other data she collected with historical data I've collected on the Sherpas. In the end, our hypotheses of that relationship didn't work, so we consoled ourselves by saying, "when you don't get the result you were expecting in science, it's because you are about to discover something even more interesting". I'm really happy for her that in fact she did - by expanding the time frame from 500 years to 40,000 !
In fact, the other paper on Sherpas and "Denisovan or Denisovan- like homonids" is even more interesting. (I paid to download both original papers from Nature). I'll get back to you when I've had more time to digest them fully. I need to read them carefully several times and then take a long meditative, non discursive walk in the woods.
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Ward Trotter
Trad climber
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I look forward to that Jan. Congrats to your friend. Ask her what she thinks of the new Denisovan findings.
I need to do a lot more digging as well---try and get this stuff straightened out to my own satisfaction. A lot to learn .
Hey, this is a great image, huh?
Red=high altitude ancestory
Green= low altitude ancestory
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