Fossils of possible new human species found in China

[chickened]

That is possible but the months of darkness with our current seasons would not allow tropical vegetation like trees. Right now the only thing living above the arctic circle is lichen tht I know of. There are theories I have heard of that claIm if the earth's axis was different that the seasons would not exist and that there would be no polar caps but a wider moderate temperature globally.

http://www.cotf.edu/ete/modules/msese/dinosaurflr/tilt.html

http://news.bbc.co.uk/2/hi/science/nature/5034026.stm
http://www.ku-prism.org/polarscientist/losttribes/Jan131897Boston.htm


These are not the ones I was looking for but they shed some light on what was possible.

I think that the term "tropical" means that area around the Earth's equator. We associate that with lush jungle vegetation that needs hot climate to live, but over time it seems that the term "tropical" has come to mean any plant/animal life that comes from a hot or warm climate - not just the stuff around the Earth's "middle belt."

The warm-hot climate at the poles may have been caused by high CO2 concentration in the atmosphere that created the so-called greenhouse effect, plus warm ocean currents, which have powerful influence on land climate. As an example, England is much farther north than where I live in coastal Massachusetts, yet southern England has palm trees and balmy winter weather, while my region is much colder, and the Puritans and Pilgrims that settled here froze their butts off because they mistakenly assumed that because Plymouth and Salem, Mass. were way farther south than where they had come from, that it must be warmer here. Turned out to be a fatal error for many of those unfortunate colonists.

 

[AquaEyes]

Could it be that the land masses currently found in the arctic circle were not there at the time the fossilized plants actually lived? I know that in Antarctica, fossils have been found which are dated from a time when the continent was further north -- it actually used to connect what is now South America with Australia. I'm not that familiar with what was posted, so I'll have to do some reading up on it. Very interesting, though -- the earth has been through quite a lot of changes.

 

[AllTheseCreatures]

I read a book that mentioned how the currents in the ancient ocean allowed warm water to circulate from pole to pole and moderated the climate in the far north and south. When Antarctica broke away from South America drifted to it's current position it became isolated from those moderating currents. I imagine the plants would go dormant in the longer dark seasons. Even tropical plants have the ability to go dormant.

 

[rufus]

I am not really sold on that "Out of Africa" idea. I suspect that is just where fossils were best preserved. Time will tell on this issue. I suspect as we begin to look elsewhere we will find contrary evidence.

Rufus

 

[chickened]

Warm ocean currents would explain the environment warm enough for tropical trees but you still have the darkness that trees cannot survive in. It would get too cold during the dark months. If the axis was at a lesser angle or no angle the seasons would not happen and some researchers suggest the globe would moderate.

Other planets poles are not the same as earth's during it's rotation around the sun, some spin horizontally to the sun as they circle the sun
.

Some suggest that with all the volcanic activity that the co2 was so thick it warmed the earth.

I read a book that mentioned how the currents in the ancient ocean allowed warm water to circulate from pole to pole and moderated the climate in the far north and south. When Antarctica broke away from South America drifted to it's current position it became isolated from those moderating currents. I imagine the plants would go dormant in the longer dark seasons. Even tropical plants have the ability to go dormant.

 

[chickened]

I agree. There is a lot we do not know.

I am not really sold on that "Out of Africa" idea. I suspect that is just where fossils were best preserved. Time will tell on this issue. I suspect as we begin to look elsewhere we will find contrary evidence.
Rufus

 

[galanie]

Yes, most of science teaching is all about telling us something as absolute fact that is in reality a theory.

 

[AquaEyes]

I am not really sold on that "Out of Africa" idea. I suspect that is just where fossils were best preserved. Time will tell on this issue. I suspect as we begin to look elsewhere we will find contrary evidence.
Rufus

It's not just fossils, though. As genetics became more advanced, we used it as a tool to offer a second-line of evidence, and it corroborates the "out of Africa" hypothesis -- more genetic diversity is found among the peoples of Africa than elsewhere, and migratory paths of ancestors can be traced through analysis of of strongly-maintained DNA (Y-chromosome and mitochondrial-DNA).

This documentary is very interesting, but somewhat long (the link below is for the first of 13 parts). If you have some time, give it a view.

 

[AquaEyes]

Yes, most of science teaching is all about telling us something as absolute fact that is in reality a theory.

No, science holds all interpretations to be tentative should new contradictory evidence be forthcoming. What happens is that in popular media and pre-college education, the language is simplified for the audience from saying "thus far, the evidence indicates that ____ is the process by which ___ happened" and instead saying "this happened this way." A fact is a piece of evidence -- something that was found, something that occurred, etc. -- and a theory is a tested explanation that ties together many facts to describe the "how" and "why" of the facts -- how was that something made, why does that occur, etc.

One example would be gravity -- that something "falls down" is a piece of evidence, a "fact of gravity." The "theory of gravity" seeks to explain why that something falls down -- attraction of a smaller body to a larger body which corresponds to the mass of the larger body -- but that theory can't be proven, only inferred through evidence supporting it. Another example, related to this thread, is evolution. At its most basic definition -- a change in the gene frequencies and inherited traits within a population over time -- that evolution happens is a fact (it has been documented, measured, etc.). When evolution is used to explain a connection between point A (a fossil) and point B (a living form), that becomes part of the theory of evolution.

An explanation that is called a theory in science has stood up to considerable testing and evidence, but is still open to evidence that might contradict it. When something is simply given as one possible explanation among many and has not withstood such "weeding out" it is called a hypothesis.

 

[GardenerGal]

chickened wrote: That is possible but the months of darkness with our current seasons would not allow tropical vegetation like trees. Right now the only thing living above the arctic circle is lichen tht I know of. There are theories I have heard of that claIm if the earth's axis was different that the seasons would not exist and that there would be no polar caps but a wider moderate temperature globally

That is possible but the months of darkness with our current seasons would not allow tropical vegetation like trees. Right now the only thing living above the arctic circle is lichen tht I know of. There are theories I have heard of that claIm if the earth's axis was different that the seasons would not exist and that there would be no polar caps but a wider moderate temperature globally.That is possible but the months of darkness with our current seasons would not allow tropical vegetation like trees. Right now the only thing living above the arctic circle is lichen tht I know of. There are theories I have heard of that claIm if the earth's axis was different that the seasons would not exist and that there would be no polar caps but a wider moderate temperature globally.That is possible but the months of darkness with our current seasons would not allow tropical vegetation like trees. Right now the only thing living above the arctic circle is lichen tht I know of. There are theories I have heard of that claIm if the earth's axis was different that the seasons would not exist and that there would be no polar caps but a wider moderate temperature globally.chickened,
Excellent point.

I believe that AquaEyes hit the nail on the head regarding plate tectonics, which I could kick myself for not having thought of in my rush to type out a post before heading out.

Though the Arctic area is very low on actual land mass now, and consists now of mostly ice floe (though global climates changing has caused lots of that ice to melt), the land mass that does exist in our time, likely was somewhere else millions of years ago.

When I was traveling in Nepal, I was amazed that fossil ammonites (a kind of prehistoric nautilus-like animal) and fossil coral were scooped up by the basketloads from the slopes of the Himalayas. People hiking in the high areas would find all kinds of fossils of creatures found on the sea floor. They dated back 40 million years to when the Indian subcontinental plate collided with the Eurasian continent and started pushing up the Earth's crust there, forming the Himalayas and Hindu Kush. The sea floor was pushed way up in the air, so now we find ammonites on the slopes of Everest. The plates are still colliding and the Himalayas continue to get higher.

Could it be that the land masses currently found in the arctic circle were not there at the time the fossilized plants actually lived? I know that in Antarctica, fossils have been found which are dated from a time when the continent was further north -- it actually used to connect what is now South America with Australia. I'm not that familiar with what was posted, so I'll have to do some reading up on it. Very interesting, though -- the earth has been through quite a lot of changes.