Posted on 07/10/2014 12:35:30 PM PDT by BenLurkin
Carson and his colleagues wanted to explore the question of whether early Amazonians had a major impact on the forest. They focused on the Amazon of northeastern Bolivia, where they had sediment cores from two lakes nearby major earthworks sites. These sediment cores hold ancient pollen grains and charcoal from long-ago fires, and can hint at the climate and ecosystem that existed when the sediment was laid down as far back as 6,000 years ago.
An examination of the two cores — one from the large lake, Laguna Oricore, and one from the smaller lake, Laguna Granja — revealed a surprise: The very oldest sediments didn't come from a rainforest ecosystem at all. In fact, the Bolivian Amazon before about 2,000 to 3,000 years ago looked more like the savannas of Africa than today's jungle environment.
The question had been whether the early Amazon was highly deforested or barely touched, Carson said.
"The surprising thing we found was that it was neither," he told Live Science. "It was this third scenario where, when people first arrived on the landscape, the climate was drier."
The pollen in this time period came mostly from grasses and a few drought-resistant species of trees. After about 2,000 years ago, more and more tree pollen appears in the samples, including fewer drought-resistant species and more evergreens, the researchers report today (July 7) in the journal Proceedings of the National Academy of Sciences. Charcoal levels also went down, indicating a less-fire-prone landscape. These changes were largely driven by an increase in precipitation, Carson said.
The earthworks predate this shift, which reveals that the diggers of these ditches created them before the forest moved in around them
(Excerpt) Read more at livescience.com ...
You answered my question; 2,000-3,000 years is not enough time not even probably 100,000 years. So there must have been continuous rainforest environments around for a long time. The forest area can grow and shrink.
Like the old white vs. dark moths things they still teach the kids in school that shows “adaptation” and “evolution”. It is just the population number of the moths that change.
“Climate changes all on it’s own. Apparently alot.”
If that 2000 - 3000 year number is correct, that to me is surprising, and is challenging. I’ve have said for a long time that climate change SHOULD be studied, and various scenarios should be thought out. Of course 2,000 years is a long time for us to adapt to new things. America’s heartland turned to a 2000 year long dust bowl would have a huge effect on the USA, but humanity would survive by growing the crops in the Sahara instead. (Unless we still have nukes, and end up having WW III over it.)
I’m more concerned with the next ice age. Would cause a world-wide drought with most of the water locked up in the ice.
“Are these scientists now telling us that all that bio diversity came into being in a mere 6,000 years?”
That’s a curious Genesis-linked number.
There’s lots more numerical links like that out there....
...more links than Darwin (piss be upon him) ever found.
I watched that same documentary with interest but became frustrated at the end because they never tried to make a connection re what the "rain forest" would have looked like when the Sahara was largely covered with shallow seas. Scouring the web revealed several efforts to make a connection that never made it into "prestigious journals". Not sure what to make of that. Maybe if they blamed humans for draining the Sahara they could have gotten published???
In any case, and just like this guy found, most conclusions were the South American rain forest was savanna type landscape when the Sahara was wetter. It becomes even more interesting when investigating a cause for this "climate change". This of course happened well past the end of the last glaciation??? Whatever. The theories run the gamut from pole shifts to alien terra formers. From most accounts the change was relatively swift, in geologic time.
The scientific community™ is nothing if not frustrating. They apparently go as far as the money and no farther. Maybe journal publishers can share the blame since they are the ones who select studies and research that make the cut? In a publish or perish environment whaddaya gonna do, but I digress...
bttt
Look at this post, sweet heart, this is close to the present and no one had a clue.
When I was a kid there was jungle and Incas, no high population areas along the Amazon.
Actually the -4026 BC Chevrolet Tahoe was a real smog box. It polluted the air all around the dirt patch where it drove burning slash grass ethanol.
I have read articles here at FR to the effect that very large deep earthquakes, such as the one that created the Indonesia tsunami, can shift axis and rotation by a tiny bit, less than 1 degree, and ultimately have huge effects on climate.
I could see a large meteor hit doing something like that as well.
We have no idea when that was constructed. Apes have no clue. Never did and never will.
There is no shortage of theories and they all have their adherents and furnish evidence, such as it is, to support them. I seem to recall the Bible describes an event, obviously during historical times, when the earth wobbled like a drunk! Eyewitness accounts??? Generally considered fairly reliable evidence. You make the call...
In a short article two years ago I proposed that the Amazon rain forest could only be a few thousand years old and not 55 million years as was currently believed.
See here: http://www.thunderbolts.info/wp/2012/10/28/the-amazon-rainforest/
Or my web.... http://www.gks.uk.com/Sahara_Desert_Amazon/
These latest finding are a major step towards supporting my stance. I see future research ultimately confirming this.
I arrived at the above conclusion by researching my theory which proposes that the Sahara & Arabian deserts are of very recent extraterrestrial origin.
http://www.thunderbolts.info/tpod/2010/arch10/100408sahara.htm
http://www.gks.uk.com/Sahara_Desert_Chaos/
I reasoned if the Sahara desert didn’t exist 3-4,000 years ago, it couldn’t have sustained the Amazon rain forest with its nutrient rich dust which blows across the Atlantic.
Gary Gilligan (catastrophist)
http://www.gks.uk.com/
This is a fascinating article but I think it is important to note this is based on evidence from the BOLIVIAN portion of the overall Amazonian rainforest, which is and was on the periphery of the rainforest proper, and still at its most extreme North-east point almost 500 miles from the Amazon river.
No telling that the forest itself was smaller or not there at all, but my (uneducated ) guess would be there were still vast regions still under forest while Bolivia was savannah. The whole rainforest area now is almost the size of the US East of the Mississippi.
I wouldn’t extrapolate an overall theory about the rainforest from evidence in Bolivia alone.
Thank you for the links.
I notice you're a writer but of course I don't know what your background is. Something occurred to me and as a matter of curiosity I wonder if you've ever looked into the possibility of massive sand blows contributing to the creation of the Sahara? I read a foreign published work within the last day or two that made some compelling arguments re volcanism, massive volcanism, being the culprit responsible for the "green glass" and the abrupt changes to North Africa. Could it be part of the answer?
Geologists have incorrectly assumed that the Earth has had all its water since its beginning. It is demonstrably incorrect yet it remains the primary reason why we do not understand our past.
There was a worldwide flood, and it was recent.
See here for some ideas: http://www.threeimpacts-twoevents.com/wp-content/uploads/2013/08/COMET-IMPACT-ANALYSIS-AND-EFFECTS-20Aug2013.pdf
So the world around us is not static? Who knew?
Mars is missing vast oceans of water - much of this fell to earth during encounters with Mars (Mars the god of war for good reason) only a few millennia ago. It is still falling to earth in the form of noctilucent clouds would be my stance. http://en.wikipedia.org/wiki/Noctilucent_cloud
A most excellent BBC documentary on the ‘dark earth’ (Terra Preta) of the Amazon. https://www.youtube.com/watch?v=-YS8I6AZRfg
A paradigm shift is going on in regards to the Amazon Rainforest; no longer can we go into any part of the forest and assume it is pristine. Millions of people (est. 5-6 million) once inhabited the region right up until the arrival of the Europeans. There is evidence many of these lived along the Amazon River.
So far an area twice the size of Spain (in the south) is now known to be anthropogenic - this is growing all the time with new archaeological discoveries.
To my mind it makes little sense that parts of the Amazon are only 2,000 yrs old while remainder is 55 million years old.
It may swing back and forth as these things have a habit of doing but ultimately I see future studies confirming my stance.
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