Posted on 01/29/2002 7:23:19 PM PST by Sabertooth
We Dodged Extinction
Pruned Family Tree Leaves Little Genetic Variety
Just one group of chimpanzees can have more genetic diversity than all 6 billion humans on the planet. (Corel)
Special to ABCNEWS.com
A worldwide research program has come up with astonishing evidence that humans have come so close to extinction in the past that its surprising were here at all.
Pascal Gagneux, an evolutionary biologist at the University of California at San Diego, and other members of a research team studied genetic variability among humans and our closest living relatives, the great apes of Africa.
Humanoids are believed to have split off from chimpanzees about 5 million to 6 million years ago. With the passage of all that time, humans should have grown at least as genetically diverse as our cousins. That turns out to be not true.
We actually found that one single group of 55 chimpanzees in west Africa has twice the genetic variability of all humans, Gagneux says. In other words, chimps who live in the same little group on the Ivory Coast are genetically more different from each other than you are from any human anywhere on the planet.
The branch lengths illustrate the number of genetic differences, not only between species, but among species as well. The pruned bush for humans shows how little genetic diversity exists. (Marco Doelling/ABCNEWS.com)
The Family Bush
The family tree shows that the human branch has been pruned, Gagneux says. Our ancestors lost much of their original variability.
That makes perfectly good sense, says Bernard Wood, the Henry R. Luce Professor of Human Origins at George Washington University and an expert on human evolution.
The amount of genetic variation that has accumulated in humans is just nowhere near compatible with the age of the species, Wood says. That means youve got to come up with a hypothesis for an event that wiped out the vast majority of that variation.
The most plausible explanation, he adds, is that at least once in our past, something caused the human population to drop drastically. When or how often that may have happened is anybodys guess. Possible culprits include disease, environmental disaster and conflict.Almost Extinct
The evidence would suggest that we came within a cigarette papers thickness of becoming extinct, Wood says.
Gagneux, who has spent the last 10 years studying chimpanzees in Africa, says the implications are profound.
If you have a big bag full of marbles of different colors, and you lose most of them, then you will probably end up with a small bag that wont have all the colors that you had in the big bag, he says.
Similarly, if the size of the human population was severely reduced some time in the past, or several times, the colors that make up our genetic variability will also be reduced.
If that is indeed what happened, then we should be more like each other, genetically speaking, than the chimps and gorillas of Africa. And thats just what the research shows.
We all have this view in our minds that we [humans] started precariously as sort of an ape-like creature and our numbers grew continuously, adds Wood. Were so used to the population increasing inexorably over the past few hundred years that we think it has always been like that.
But if it had, Gagneux notes, our genetic variability should be at least as great as that of apes.A Stormy Past
Gagneux is the lead author of a report that appeared in the April 27 issue of the Proceedings of the National Academy of Sciences. The study, carried out with researchers in Germany, Switzerland and the United States, is the first to examine large numbers of all four ape species in Africa.
We can do that now because new technology allows us to non-invasively take some hair, or even some fruit that these apes chew, and then we get their DNA from a couple of cells that stick to a hair or a piece of fruit they chewed.
Then they compared the DNA variability of apes and chimps to that of 1,070 DNA sequences collected by other researchers from humans around the world. They also added the DNA from a bone of a Neanderthal in a German museum. The results, the researchers say, are very convincing.
We show that these taxa [or species] have very different amounts and patterns of genetic variation, with humans being the least variable, they state.
Yet humans have prevailed, even though low genetic variability leaves us more susceptible to disease.
Humans, with what little variation they have, seem to maximize their genetic diversity, Gagneux says.
Its ironic, he notes, that after all these years the biggest threat to chimpanzees is human intrusion into their habitats. When he returned to Africa to study a group of chimps he had researched earlier, Gagneux found them gone.
They were dead, he says, and I mean the whole population had disappeared in five years.
Yet as our closest living relatives, chimps still have much to teach us about ourselves.
Lee Dyes column appears Wednesdays on ABCNEWS.com. A former science writer for the Los Angeles Times, he now lives in Juneau, Alaska.
What excuses have I made for God? I described what I thought God had in mind with a perfect creation. How was that an excuse? What's your axe to grind here? Some mean ole Christian make you mad once, twice?
Pray or clean animals were taken on the Ark in larger numbers (seven pairs) to give them a jump-start.
Later, when the Law of Moses was given the clean and unclean animals were used as meat as well as sacrifice. It became necessary for dietary proposes for the list to be further refined.
Clear now?
A. Cricket
Can you translate this into English?
Also, why does god change His mind so often. Prior to the flood, people werre supposed to be vegetarians. After the flood, omnivores. After the Exodus, omnivors with restrictions. After Jesus, omnivores again. After Muhammed, restrictions again.
Clean used as sacrifice Genesis 8:20
Technically this is after the flood but it is before the Covenant so the same rules that were before the flood are still in place.
Seven pairs of clean animals taken on the ark. Genesis 7: 2
However as to what I am sure is your main question as to that predator and omnivores were unclean and herbivores clean before the flood that is something I learned from a Rabbi. Sorry, but I do not have the Talmudic reference at hand and I am fairly sure it is not in the Tanach. I will look it up and Freepmail it to you.
A. Cricket
Can you translate this into English?
Later, when the Law of Moses was given the clean and unclean animals were used as meat as well as sacrifice.
Later, when the Law of Moses was given, the clean animals were to be used as meat as well as sacrifice.
Did that help? If not please tell me what you do not understand and I will try to explain.
Also, why does god change His mind so often.
You want me to explain His working to you? Yikes! I recommend that you read the 38th chapter of Job to understand why I am not touching that one.
Prior to the flood, people were supposed to be vegetarians. After the flood, omnivores. After the Exodus, omnivores with restrictions. After Jesus, omnivores again. After Muhammad, restrictions again.
A question I can sort of answer. But I will break it apart if you don't mind to make it easier to work with. Please understand that my answers are not in depth.
Prior to the flood, people were supposed to be vegetarians.
Man was not meant to kill. That is something that was changed after the Fall. The first record we have of a man making a voluntary kill is Cain and Abel where Abel sacrificed one (or more) of his flock. Still men did not kill to eat. Since we started as vegetarians we might not have even thought of animals as food but that is just speculation.
After the flood, omnivores.
There were some great physical changes that came about after the flood. One of them was that mans life span began to shorten. Maybe there was some kind of physical change and we required certain nutrients that are not available only in veggies.
After the Exodus, omnivores with restrictions.
The Law was given for more then health reasons although there is a book called "None of these Diseases" which argues that many of them were just that.
My teachings was that it was a reminder to you every day to remember that you were different. When you looked at your shirt sleeve of either pure linen or pure wool, sat down to dinner, yoked your two donkeys or two oxen together to plow (you may not yolk a donkey and a ox together) or obeyed any of the other Laws you were to remember. You had a special covenant with Him. Much is required of you but you are blessed with much as well.
After Jesus, omnivores again.
You are referring to Peter and the sheet I presume. It is important to understand that Jewish restrictions did not change but Gentiles were not bound by the same Law.
Gentiles were instructed to obey the following rules:
1.) No idol worship
2.) No sex outside of marriage
3.) No eating of things strangled
4.) No blood.
After Muhammed, restrictions again
My request to study Islamic law was refused by the local Imam so I can offer no insight as to why they believe this.
Hope this helps. G'night!
A. Cricket
If you think that's fun, check out yourself doing Curlies on the floor over the same old bad assumption.
It is not logically necessary for a perfect Creator to Create a perfect Creation. All of your "Aha!" discoveries of imperfections in nature amount to a colossal "so what?"
Your materialist dogma betrays you when you assume the purpose of Creation is Creation. Hence, your errant assumption that God must immediately Create perfection.
Consider that God is a parent. He's the Father.
Does a father treat an infant like a toddler? A toddler like a teen? No.
Does that mean that the father has changed his mind? No, the child has grown, and is ready for the next level of rearing.
So it is with God and man.
His Terra project is world renowned. Here is one list of his accomplishments:
John R. Baumgardner, Ph.D. Geophysics/Space Physics
Education:
B.S. Electrical Engineering, Texas Tech University - 1968
M.S. Electrical Engineering, Princeton University - 1970
M.S. Geophysics and Space Physics, UCLA - 1981
Ph.D. Geophysics and Space Physics, UCLA - 1983
Organizations:
American Geophysical Union Mineralogical Society of America
Professional Experience:
Technical Staff Member/Scientist - Los Alamos National Laboratory, Theoretical Division, New Mexico (1984 - Present).
Member of Technical Staff and Consultant - Rockwell International, Rocketdyne Division, Laser Department (1978-1979, 1981-1984).
Graduate Research Assistant - University of California, Los Angeles, Dept. of Earth and Space Sciences (1979-1983).
Consultant - R & D Associates (1980-1981).
Project Officer - U. S. Air Force, Air Force Weapons Laboratory, Laser Division, Kirtland AFB, New Mexico (1971-1975).
Current Research Interests:
Three-dimensional numerical simulation of planetary mantle dynamics, global climate change, and nonlinear rheological behavior.
Development of efficient hydrodynamics methods, suitable for 3-D, both explicit and implicit, for massively parallel supercomputers.
Publications:
W.-S. Yang and J. R. Baumgardner, "Matrix-dependent transfer multigrid method for strongly variable viscosity infinite Prandtl number thermal convection," Geophys. and Astrophys. Fluid Dyn., in press, 2000.
H. R. Wenk, J. R. Baumgardner, C. N. Tome, and R. Lebensohn, "A deformation model to explain anisotropy of the inner core," J. Geophys. Res., in press, 2000.
M. A. Richards, H.-P. Bunge, C. Lithgow-Bertelloni, and J. R. Baumgardner, "Mantle convection and plate motion history: Toward general circulation models," History and Dynamics of Global Plate Motions, AGU Monograph Series, 1999.
J. R. Baumgardner and W.-S. Yang, "Earthlike mantle convection from relatively simple rheology," (abstract) Eos, Trans. Am. Geophys. Union, 80, (1999 Fall Meeting Supplement), F26, 1999.
M. A. Richards, W.-S. Yang, and J. R. Baumgardner, "The effectiveness of finite yield stress in obtaining platelike surface velocities," (abstract) Eos, Trans. Am. Geophys. Union, 80, (1999 Fall Meeting Supplement), F962, 1999.
W.-S. Yang and J. R. Baumgardner, "Feasibility of the lava lamp model for the Earth's mantle," (abstract) Eos, Trans. Am. Geophys. Union, 80, (1999 Fall Meeting Supplement), F941, 1999.
D. R. Stegman, M. A. Richards, and J. R. Baumgardner, "A parallel implementation of Lagrangian tracers in TERRA," (abstract) Eos, Trans. Am. Geophys. Union, 80, (1999 Fall Meeting Supplement), F950, 1999.
C. C. Reese, V. S. Solomatov, and J. R. Baumgardner, "Impacts and the thermal evolution of Mars," (abstract) Eos, Trans. Am. Geophys. Union, 80, (1999 Fall Meeting Supplement), F618, 1999.
John R. Baumgardner, Mark A. Richards, Woo-Sun Yang, and Carolina R. Lithgow-Bertelloni, "3-D Spherical Models of Plate Motion With Laterally Varying Rheology," (abstract) Eos, Trans. Am. Geophys. Union, 79, (1998 Fall Meeting Supplement), F911, 1998.
H.-P. Bunge, M. A. Richards, C. Lithgow-Bertelloni, J. R. Baumgardner, S. P. Grand, and B. A. Romanowicz, "Time scales and heterogeneity structure in geodynamic earth models," Science, 280, 91-95, 1998.
Hans-Peter Bunge, Mark A. Richards, and John R. Baumgardner, "A sensitivity study of 3-D spherical mantle convection at 108 Rayleigh number: effects of depth-dependent viscosity, heating mode, and an endothermic phase change," J. Geophys. Res., 102, B6, 11991-12007, 1997.
John R. Baumgardner and Woo-Sun Yang, "A finite element multigrid formulation for variable viscosity in 3-D spherical geometry," (abstract) Eos, Trans. Am. Geophys. Union, 77, (Fall Meeting Supplement), F750, 1996.
Hans-Peter Bunge, Mark A. Richards, and John R. Baumgardner, "The effect of depth-dependent viscosity on the planform of mantle convection," Nature, 379, 436-438, 1996.
Hans-Peter Bunge and John R. Baumgardner, "Mantle convection modeling on parallel virtual machines," Computers in Physics, 9, 207-215, 1995. J. R. Baumgardner, "Thermal runaway in the mantle" (abstract) Eos, Trans. Am. Geophys. Union, 75, 687, 1994.
John R. Baumgardner, "3-D numerical investigation of the mantle dynamics associated with the breakup of Pangea," in Flow and Creep in the Solar System: Observations, Modeling, and Theory, D. B. Stone and S. K. Runcorn, eds., NATO ASI Series C, Vol. 391, 207-224, 1993.
John Baumgardner, "3-D numerical investigation of the mantle dynamics associated with the breakup of Pangea," (abstract) Eos, Trans. Am. Geophys. Union, 73, 1992 Fall Meeting Abstract Volume, 576-577, 1992.
M. A. Moreno, G. Schubert, J. Baumgardner, M. G. Kivelson, and D. A. Paige, "Io's volcanic and sublimation atmospheres," Icarus, 93, 63-81, 1991.
John R. Baumgardner, "Application of supercomputers to 3-D mantle convection," in The Physics of the Planets, S. K. Runcorn, ed., John Wiley and Sons, 199-231, 1988.
J. Baumgardner, M. A. Moreno, G. Schubert, and M. G. Kivelson, "Two classes of volcanic eruptions and their corresponding atmospheres on Io," Bull. Am. Astr. Assoc., 19(3), 856, 1987.
John R. Baumgardner, "Three-dimensional treatment of convective flow in the earth's mantle," J. Stat. Phys., 39, 501-511, 1985.
John R. Baumgardner and Paul O. Frederickson, "Icosahedral discretization of the two-sphere," SIAM J. Numer. Anal., 22, 1107-1115, 1985.
Peter Bird and John Baumgardner, "Fault friction, regional stress, and crust-mantle coupling in southern California from finite element models," J. Geophys. Res., 89, No. B3, 1932-1944, 1984.
John R. Baumgardner and Paul O. Frederickson, "Three-dimensional treatment of mantle convection," (abstract) Eos, Trans. Am. Geophys. Union, 63, 1105, 1982.
Look at the paper he co-authored with Peter Bird in 1984. A few years before I had collaberated on a similar paper. Finite element models are very tricky to work with. They are reasonable equations to use to describe stress fields, etc., when you are considering a moment in time (like a snapshot). But when you model with them, and attempt reinterative processes, the whole thing breaks down.
Sorry, it's an academic thing. The bottom line is, a computer model must be constrained by real world observations, and then tested for predictability. Baumgardner's concept that crustal recycling can occur over the course of weeks or months has no support in academia. That his computer model can be made to generate these weird and outrageous results doesn't mean there is any validity to it. The entire concept has huge holes. If Baumgardner had a better understanding of rock mechanics and structural geology, he would realize his concept is fatally flawed.
Lest you think I'm just on Baumgardner's case, do a google on John Suppe, Professor of Geology at Princeton. He's a structural geologist and a creationist, and I wonder if he supports Baumgardner's rapid subduction concept.
A few years ago there was an astrophysicist by the name of Thomas Gold (if memory serves me). He somehow came to the conclusion that most crustal hydrocarbons (petroleum, natural gas, etc.) were the result of the degassing of the mantle - primarily inorganic methane. Somehow he talked a Nordic country into testing his pet theory by drilling an oil well in a meteorite impact crater.
The whole thing was a terrific and costly failure. Professor Gold, however, kept his blinders on and continued to push his idea. He should have studied a little petroleum geology first.
There is nothing wrong scientifically with proposing a hypothesis and putting it to the test. But how many "free energy" black boxes, or cold fusion devices to you have to look at before you realize you are being scammed?
AC->There were some great physical changes that came about after the flood. One of them was that mans life span began to shorten. Maybe there was some kind of physical change and we required certain nutrients that are not available only in veggies.
One explanation I've seen of this was that the flood was composed of the water vapors above the earth. It is postulated that there was a water canopy of sorts and that this canopy greatly restricted harmful radiation. Basically the world before the flood was a much more benign place than the world after the flood. With increased challenges came an increase in nutritional needs and a shorter lifespan. (or at least that's what I remember of it)
GSA(P)
The idea that nutritional needs change with time in a God directed universe seems silly. Same with the notion that killing is OK or NOTOK at the whim of God. As for the possibility that "clean" and "unclean" are statements about health and hygiene, why not simply say that some animals carry diseases?
Err... you're way off in la-la land there, sorry, and I'm not taking this from the POV of THOU ART D*MMED! The "world wide" flood is well documented and accepted by archaeologists and ethnologists alike; it's called the end of the Wurm Glaciation. It caused massive changes in weather patterns and rising water levels throughout the world. Since every major culture has a "flood" myth, there had _better_ have been a flood.
Especially in the Black Sea basin, there was a sudden and catastrophic rise, with water moving as much as three miles per hour. There was no way that humans could have outraced it on foot. The most likely direct explanation (which does _not_ preclude equality with the Christian explanation, if you accept that in an oral history things are going to get a tad allegorical) of the Noah myth is that a patriarch (or, alternatively, a nutcase, or, alternatively, the prehistoric equivalent of Murtaugh in the lethal weapon movies who just wanted a boat to tinker with) of one of the villages created a raft boat for reasons more or less unknown. And when the water started rising he piled his kids, his goats and his wife on the raft and floated to safety. I think that _I'd_ be looking to Divine Providence if my really odd hobby saved my life and the life of my family and best pair of goats. (And he led all the animals two by two...)
Now, one like _Waterworld_ (which is just the Noah flood, showing that True Believer Greens and True Believe Christians are alike in their belief in Revealed Truth) did not happen. But there was one _h*ll_ of a flood (and possibly alot of rain and even a rainbow or two) and dat's da trut'!
Over all, I found the article vey illuminating. And for the "there is no evolution" crowd, you can have your cake and eat it too. Although they discuss evolution, the data works just as well with "conscious creation" or whatever it's called. If God placed us on Earth x thousand years ago, there would be natural variation. (Blacks, browns, yellows, etc.) But there would be less (unless he was being deliberately sneaky) than "natural" species.
So stick your fingers in your ears and chant, "Nyah, nyah, nyah." It's a great way to avoid unpleasant realities.
You are quite welcome.
But I think you are aware that I consider your answer (and some others posted on this thread) to involve some serious rationalizations.
I knew I detected something there. It is SO nice to be right. It happens far to rarely.
Cannot answer for other people but I will be glad to explain my reasoning.
The idea that nutritional needs change with time in a God directed universe seems silly.
Why? If you live in different areas of the world your eating habits change. 100 years ago if you live in a cold climate you required a diet higher in fat then if you lived in a warmer climate. That has changed because of central heating and warmer houses. If you smoke you require more vitamin C then if you dont. Change in environment results in changes in diet. Even from childhood to adulthood our nutritional needs change.
Same with the notion that killing is OK or NOTOK at the whim of God.
I think you misunderstood me. It is not a case of Okay and Not Okay but of needed and not needed. Blood was always required for the redemption from sin but as long as the human race was without sin there was no need for blood to be shed.
As for the possibility that "clean" and "unclean" are statements about health and hygiene, why not simply say that some animals carry diseases?
Poetic license? ~smile
As I pointed out that was only part of the reason. The rest was to draw a line, make a distention between the Jews (chosen) and the rest of the world (not chosen) The Jews were offered certain incentives in exchange for certain actions on their part.
A. Cricket
This thread has certainly wandered into some interesting places.
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