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Author Topic:   Age of Grand Canyon and Cave Speleothems
Coragyps
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Posts: 5295
From: Snyder, Texas, USA
Joined: 11-12-2002
Member Rating: 3.6


(2)
Message 31 of 46 (681475)
11-25-2012 7:36 PM
Reply to: Message 20 by RAZD
11-23-2012 11:09 AM


Neither do I, so we will need someone with access (Coragyps?). That would be a fun map to make.

There are couple of such in the paper and the supplementary information - and it's all free open access if you register:

http://www.sciencemag.org/search

Searching volume 319, page 1377 will bring it up. Most Science from 1880 to a year before this week's issue is free. Nature is not so generous, even to suscribers. PNAS is pretty good to the public, though.

http://www.nature.com/nature/index.html
http://www.pnas.org/content/by/year

Oh - and I am always happy to send Science or Nature pdfs to anyone here if you PM me an email address.

Edited by Coragyps, : additional stuff


This message is a reply to:
 Message 20 by RAZD, posted 11-23-2012 11:09 AM RAZD has responded

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RAZD
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Posts: 19225
From: the other end of the sidewalk
Joined: 03-14-2004
Member Rating: 2.6


Message 32 of 46 (681477)
11-25-2012 7:56 PM
Reply to: Message 31 by Coragyps
11-25-2012 7:36 PM


link to article
Hi Coragyps,

I figured you'd come through.

Thanks


we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
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This message is a reply to:
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RAZD
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Posts: 19225
From: the other end of the sidewalk
Joined: 03-14-2004
Member Rating: 2.6


(2)
Message 33 of 46 (681892)
11-28-2012 1:04 PM
Reply to: Message 31 by Coragyps
11-25-2012 7:36 PM


Timing issues for creationists
Hi Coragyps,

I signed in and went to
http://www.sciencemag.org/content/319/5868/1377.full?sid=...

and also downloaded the PDF.

Thanks.

Two different dating methods were used on each speleothem: (1)238U/206Pb and (2) 235U/207Pb. The dates derived, while slightly different, are within the margins of error for each one.

I was also thinking that just the existence of these speleothems presents an additional problem for creationists:

IF the canyon was carved by flood drainage, then the caves occurred after the flood.

The speleothems have to be deposits after the caves were formed, so they too occurred after the flood. The youngest speleothem is 0.8 million years, and it is at the top end of the canyon.

IF there has been no change in radioactive decay rates since the flood, then the canyon is OLD, way too old for the YEC model.

Enjoy.


we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
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kofh2u
Member (Idle past 1411 days)
Posts: 1162
From: phila., PA
Joined: 04-05-2004


Message 34 of 46 (681953)
11-28-2012 8:48 PM
Reply to: Message 1 by RAZD
11-21-2012 4:38 PM


(b) - Note that I have shown in previous threads why Hovind's explanation is bogus and doesn't work by his own argument that water does not flow uphill -- where the Grand Canyon crosses the ridge is not the lowest point of the ridge, but up on a slope between two lower points, so if he was correct then the canyon would be in a different location

Hoping that this post is accepted as on topic, I add to your correct anshing of Creationists' interpretations of Genesis that the first six "days" could not be 24 hour durations since Genesis specificallytells us that the 24 hour Solar Day was created in the 3rd duration of the cosmic unfolding, when the Sun and Moon were made time keepers for the Earth Clock.

It makes more sensible reading comprehension of Genesis to understand the first six durations were geological eras marking the History of the Earth by well placed catastrophic markers that separate the six layers.

Edited by kofh2u, : No reason given.


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Coyote
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Posts: 6027
Joined: 01-12-2008
Member Rating: 2.5


Message 35 of 46 (681955)
11-28-2012 9:19 PM
Reply to: Message 34 by kofh2u
11-28-2012 8:48 PM


Your graphic, both in your post and in the original, are too small to read.

Do you have a larger version you could point us to?


This message is a reply to:
 Message 34 by kofh2u, posted 11-28-2012 8:48 PM kofh2u has not yet responded

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 Message 36 by Percy, posted 11-29-2012 6:45 AM Coyote has not yet responded

  
Percy
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Posts: 16168
From: New Hampshire
Joined: 12-23-2000
Member Rating: 3.1


(1)
Message 36 of 46 (681968)
11-29-2012 6:45 AM
Reply to: Message 35 by Coyote
11-28-2012 9:19 PM


Found a version about halfway down this page:

http://palaeos.com/timescale/index.html

Hmmm, maybe I can reproduce it here, giving it a try:

Chaotian Era
Chaotian Eon
This era begins with the formation of the Solar System and the Earth from planetesimals in the solar nebula. Mineral evolution begins at this time (although presumably it has already occurred many times in other, early, solar systems.
Hadean Era
Hadean Eon
The name says it all; a hellish period lasting some 760 million years, when the Earth was subject to frequent bombardment by comets, asteroids, and other planetary debris. This era begins when a Mars-sized body struck the original Earth, pulverizing both, and reforming into the current Earth-moon binary. Gradually the molten Earth cools, outgassing of first atmosphere and oceans, bombardment by left-over planetesimal and debris. The Hadean eon was characterized by extensive volcanism and formation of the first crust. Following a second period of cosmic bombardment, by the end of the Hadean, the Earth had an atmosphere (unbreathable to most organisms today), and oceans filled with water.
Archean Era
Archean Eon
Lasting more than twice as long as the Phanerozoic eon, the Archean was a time when diverse microbial life flourished in the primordial oceans, and the continental shields developed from volcanic activity. The reducing (anaerobic) atmosphere enabled Archaea (anaerobic microbes) to develop, and plate tectonics followed a regime of continental drift different to that of the Proterozoic and later. During this era, one type of organism, the Cyanobacteria (blue-green algae) produced oxygen as a metabolic by-product; the eventual build-up of this highly reactive gas was to eventually prove fatal to many life-forms, and converted the atmosphere from.
Proterozoic Era
Proterozoic Eon
The Proterozoic, which lasted even longer than the Archean Era, saw the atmosphere changes from reducing to oxygenated, driving the original anaerobic inhabitants of the Earth into a few restricted anoxic refuges and enabling the rise of aerobic life (both prokaryote and the more complex eukaryotic cell, which requires the high octane boost that oxygen enables.) Stromatolites (colonial cyanobacteria), which had appeared during the Archean, were common. The modern regime of continental drift began, and saw the formation of supercontinent of Rodinia, and several extensive ice ages. Late in the Proterozoic a runaway icehouse effect meant that the preceding warm conditions were replaced by a "Snowball Earth" with ice several kilometers deep covering the globe. Warming conditions saw the short-lived Ediacarian biota and finally the appearance of first metazoa.

Paleozoic Era
Paleozoic Era
Early in the 300 million year history of the Paleozoic, atmospheric oxygen reached its present levels, generating the ozone shield that screens out ultraviolet radiation and allows complex life to live in the shallows and finally on land. This era witnessed the age of invertebrates, of fish, of tetrapods, and (during the Permian) reptiles. From the Silurian on, life emerged from the sea to colonize the land, and in the later Paleozoic pteridophyte and later gymnospermous plants flourished. The generally mild to tropical conditions with their warm shallow seas were interspersed with Ordovician and Permo-Carboniferous ice ages. Towards the end of the Paleozoic the continents clustered into the supercontinent of Pangea, and increasingly aridity meant the end of the great Carboniferous swamps and their unique flora and fauna. The Paleozoic was brought to an end by the end Permian mass-extinction, perhaps the most severe extinction the planet has seen.
Mesozoic Era
Mesozoic Era
Lasting little more than half the duration of the Paleozoic, this was a spectacular time. The generalized archosaurian reptiles of the Triassic gave way to the dinosaurs, a terrestrial megafauna the like of which the Earth has not seen before or since. While dinosaurs dominated the land, diverse sea-reptiles ruled the oceans, and invertebrates, especially ammonites, were extremely diverse. Pterosaurs and later birds took to the sky. Mammals however remained small and insignificant. Climatic conditions remained warm and tropical worldwide. The supercontinent of Pangea broke up into Laurasia and Gondwana, with different dinosaurian faunas evolving on each. During this era modern forms of corals, insects, new fishes and finally flowering plants evolved. At the end of the Cretaceous period the dinosaurs and many other animals abruptly died out, quite likely the result of an asteroid impact and associated extensive volcanism (acid rain)
Cenozoic Era
Cenozoic Era
With the extinction of the dinosaurs and the end of the Mesozoic, the mammals swiftly inherit the Earth. Archaic mammals co-existed with birds and modern reptiles and invertebrates. The current continents emerged, and the initial tropical conditions were replaced by a colder drier climate, possibly caused by the Himalayan uplift. The appearance of grass meant the rise of grazing mammals, and the cooler drier world allowed modern mammalian groups to evolve, along with other lineages now extinct and a few archaic hold-overs. Among the newcomers were the anthropoid apes that culminated in the australopithecine hominids of Africa. Decreasing temperatures and a polar landmass of Antarctica resulted in a new Ice Age. Most recently, in the blink of an eye geologically speaking, this era saw the rise of Man (Homo erectus, Neanderthal and Cro-Magnon) and use of stone tools and fire, the extinction of Megafauna, and civilization and human activities that have transformed the globe, but at a cost of great environmental destruction.

That should be good enough.

--Percy

Edited by Percy, : Minor cleanup.


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Replies to this message:
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New Cat's Eye
Member
Posts: 11813
From: near St. Louis
Joined: 01-27-2005
Member Rating: 1.6


Message 37 of 46 (681975)
11-29-2012 10:24 AM
Reply to: Message 34 by kofh2u
11-28-2012 8:48 PM


It makes more sensible reading comprehension of Genesis to understand the first six durations were geological eras marking the History of the Earth by well placed catastrophic markers that separate the six layers.

No, we refuted that a few weeks ago when you posted it here: Message 205.

You should start a new topic in the coffee house, just copy and paste one of your posts there, and then we'll have a whole thread devoted to it and we can show where and how you're so wrong.

Kofh2u, please don't start a Coffee House thread for cosmology or geology topics. Creation/evolution topics should be proposed over at Proposed New Topics.

Edited by Admin, : Admin comment.


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RAZD
Member
Posts: 19225
From: the other end of the sidewalk
Joined: 03-14-2004
Member Rating: 2.6


Message 38 of 46 (682047)
11-29-2012 5:11 PM
Reply to: Message 37 by New Cat's Eye
11-29-2012 10:24 AM


topic drift
Topic is Grand Canyon age data provided by speleothems.

The data refutes YEC models for:

  1. the age of the earth -- the youngest part of the canyon is 0.8 million years according to the data.
  2. the formation of the canyon -- west to east instead of east to west so it would not be due to flood dam overflow (which should be a dead issue anyway for other reasons).
  3. that earth age data is misinterpreted due to pre-flood differences in radioactive decay -- they formed after the canyon had cut down to the elevations of the caves and the subsequent formation of the caves, so this decay occurred post flood.

I may figure out a few more wrinkles, but that should be enough for now.

Enjoy.


we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

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 Message 37 by New Cat's Eye, posted 11-29-2012 10:24 AM New Cat's Eye has acknowledged this reply

  
NoNukes
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Posts: 10065
From: Central NC USA
Joined: 08-13-2010
Member Rating: 1.9


Message 39 of 46 (682171)
11-30-2012 11:40 AM


Date of creation of grand canyon
As I drove into work today, I heard a story on NPR discussing revisions to dating of the Grand Canyon. Apparently, some kind of helium dating technique when applied to soil samples from the canyon produces dates of about 70 million years, whereas the canyon has previously been thought to be only a few million years old.

I don't know anything at all about this topic, but I'd appreciate being filled in by people who do. Pointers to some reading material would also be helpful.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

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Replies to this message:
 Message 40 by Taq, posted 11-30-2012 11:49 AM NoNukes has acknowledged this reply
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Taq
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Posts: 7263
Joined: 03-06-2009
Member Rating: 3.7


Message 40 of 46 (682172)
11-30-2012 11:49 AM
Reply to: Message 39 by NoNukes
11-30-2012 11:40 AM


Re: Date of creation of grand canyon
As I drove into work today, I heard a story on NPR discussing revisions to dating of the Grand Canyon. Apparently, some kind of helium dating technique when applied to soil samples from the canyon produces dates of about 70 million years, whereas the canyon has previously been thought to be only a few million years old.

My first reaction is that they are dating the age of the sediments that make up the walls of the canyon. I don't think there is a problem with the canyon walls being much older than the river system that cut through them.


This message is a reply to:
 Message 39 by NoNukes, posted 11-30-2012 11:40 AM NoNukes has acknowledged this reply

  
ooh-child
Member
Posts: 182
Joined: 04-10-2009


Message 41 of 46 (682175)
11-30-2012 11:59 AM
Reply to: Message 39 by NoNukes
11-30-2012 11:40 AM


Re: Date of creation of grand canyon
This is the article I read yesterday:

http://www.washingtonpost.com/...01f-5f55b193f58f_story.html

"The canyon isn’t 6 million years old, they say, but more like 70 million years old. If this order-of-magnitude challenge to the orthodoxy holds up, it would mean the Grand Canyon has been around since the days of T. rex.

“Our data detects a major canyon sitting there about 70 million years ago,” said Rebecca Flowers, 36, a geologist at the University of Colorado and the lead author of a paper published online Thursday by the journal Science. “We know it’s going to be controversial.”


This message is a reply to:
 Message 39 by NoNukes, posted 11-30-2012 11:40 AM NoNukes has acknowledged this reply

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Coragyps
Member
Posts: 5295
From: Snyder, Texas, USA
Joined: 11-12-2002
Member Rating: 3.6


Message 42 of 46 (682181)
11-30-2012 12:35 PM
Reply to: Message 41 by ooh-child
11-30-2012 11:59 AM


Re: Date of creation of grand canyon
From Science:

Flowers and Kenneth Farley, a geologist at the California Institute of Technology in Pasadena, are employing yet another approach: using concentrations of the noble gas helium in calcium phosphate minerals called apatites found in the canyon's rocks. Helium in these minerals can fluctuate in several ways over time: For instance, concentrations increase due to the radioactive decay of uranium and thorium in the apatites. As long as the apatites remain deep within Earth—at a temperature above 70°C—the helium can escape from the minerals through diffusion, Flowers explains. But as the minerals rise toward the Earth's surface—or as erosion carves a canyon downward—the rocks cool, trapping the helium within the apatites so that it begins to accumulate. So, helium concentrations in apatite can help scientists estimate when the rocks cooled.

In the new study, published online today in Science, Flowers and Farley analyzed four rock samples from the western portions of the Grand Canyon and four from the eastern reaches of the gorge. The pattern of helium concentrations in the samples suggests that substantial parts of the western portion of the Grand Canyon were already carved to within a few hundred meters of their current depth by about 70 million years ago and that erosion hasn't increased dramatically in recent eras, the researchers report. That's a far cry from the 5-million-to 6-million-year-old age suggested by previous research, and is about quadruple the oldest previous estimate from other teams for the canyon's age.

and

Nevertheless, not everyone is convinced by the team's evidence. Karl Karlstrom, a structural geologist at the University of New Mexico, Albuquerque, describes the findings as "out in left field." His team has also analyzed helium concentrations in apatites that were collected just a couple of kilometers downstream from where Flowers and Farley collected their samples in the western Grand Canyon. And their preliminary results, Karlstrom says, bolster the notion of a young gorge. Those soon-to-be-published results suggest that those rocks were still between 50° and 60°C—implying that they were well over 1 kilometer below the surface of Earth's crust—between 15 million and 20 million years ago.

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RAZD
Member
Posts: 19225
From: the other end of the sidewalk
Joined: 03-14-2004
Member Rating: 2.6


Message 43 of 46 (682236)
11-30-2012 4:41 PM
Reply to: Message 42 by Coragyps
11-30-2012 12:35 PM


Re: Date of creation of grand canyon
Hi NoNukes, Taq, ooh-child, and Coragyps,

NoNukes: As I drove into work today, I heard a story on NPR discussing revisions to dating of the Grand Canyon. Apparently, some kind of helium dating technique when applied to soil samples from the canyon produces dates of about 70 million years, whereas the canyon has previously been thought to be only a few million years old.

ooh-child: This is the article I read yesterday:
http://www.washingtonpost.com/...01f-5f55b193f58f_story.html
"The canyon isn’t 6 million years old, they say, but more like 70 million

The speleothems date the most recent erosion being 0.8 million years and the oldest at 17 million years. These are uranium-lead dates (two methods) taken on speleothems formed underwater in caves along the canyon walls.

These can be taken as minimum dates, because the caves need to form before the speleothems can form, however they do need to be underwater to form, which means water levels of the canyon need to be higher than the caves.

Taq: My first reaction is that they are dating the age of the sediments that make up the walls of the canyon. I don't think there is a problem with the canyon walls being much older than the river system that cut through them.

That certainly would seem to be a possibility. Tectonic activity with the uplift could also cause fracturing that would allow easier escape paths for Helium.

Enjoy.

Edited by RAZD, : added


we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

This message is a reply to:
 Message 42 by Coragyps, posted 11-30-2012 12:35 PM Coragyps has not yet responded

  
kofh2u
Member (Idle past 1411 days)
Posts: 1162
From: phila., PA
Joined: 04-05-2004


Message 44 of 46 (682266)
11-30-2012 6:29 PM
Reply to: Message 36 by Percy
11-29-2012 6:45 AM


The SEVEN "DAYS" WERE GEOLOGICAL ERAS
1. Formative/Cosmologic Era-Hadean Era/ = First Day

2. Hadean Era-Archaean Era/ = Second Day

3. Archaean Era-Proterozoic Era/ = Third Day

4. Proterozoic Era-Paleozoic Era/ = Fourth Day

5. Paleozoic Era-Mesozoic Era/ = Fifth Day

6. Mesozoic Era-Cenozoic Era/ = Six Day

7. Cenozoic Era-Common Era/ = Seventh Day

//////////

Chaotian Era
Chaotian Eon
This era begins with the formation of the Solar System and the Earth from planetesimals in the solar nebula. Mineral evolution begins at this time (although presumably it has already occurred many times in other, early, solar systems.
Hadean Era
Hadean Eon
The name says it all; a hellish period lasting some 760 million years, when the Earth was subject to frequent bombardment by comets, asteroids, and other planetary debris. This era begins when a Mars-sized body struck the original Earth, pulverizing both, and reforming into the current Earth-moon binary. Gradually the molten Earth cools, outgassing of first atmosphere and oceans, bombardment by left-over planetesimal and debris. The Hadean eon was characterized by extensive volcanism and formation of the first crust. Following a second period of cosmic bombardment, by the end of the Hadean, the Earth had an atmosphere (unbreathable to most organisms today), and oceans filled with water.
Archean Era
Archean Eon
Lasting more than twice as long as the Phanerozoic eon, the Archean was a time when diverse microbial life flourished in the primordial oceans, and the continental shields developed from volcanic activity. The reducing (anaerobic) atmosphere enabled Archaea (anaerobic microbes) to develop, and plate tectonics followed a regime of continental drift different to that of the Proterozoic and later. During this era, one type of organism, the Cyanobacteria (blue-green algae) produced oxygen as a metabolic by-product; the eventual build-up of this highly reactive gas was to eventually prove fatal to many life-forms, and converted the atmosphere from.
Proterozoic Era
Proterozoic Eon
The Proterozoic, which lasted even longer than the Archean Era, saw the atmosphere changes from reducing to oxygenated, driving the original anaerobic inhabitants of the Earth into a few restricted anoxic refuges and enabling the rise of aerobic life (both prokaryote and the more complex eukaryotic cell, which requires the high octane boost that oxygen enables.) Stromatolites (colonial cyanobacteria), which had appeared during the Archean, were common. The modern regime of continental drift began, and saw the formation of supercontinent of Rodinia, and several extensive ice ages. Late in the Proterozoic a runaway icehouse effect meant that the preceding warm conditions were replaced by a "Snowball Earth" with ice several kilometers deep covering the globe. Warming conditions saw the short-lived Ediacarian biota and finally the appearance of first metazoa.
Paleozoic Era
Paleozoic Era
Early in the 300 million year history of the Paleozoic, atmospheric oxygen reached its present levels, generating the ozone shield that screens out ultraviolet radiation and allows complex life to live in the shallows and finally on land. This era witnessed the age of invertebrates, of fish, of tetrapods, and (during the Permian) reptiles. From the Silurian on, life emerged from the sea to colonize the land, and in the later Paleozoic pteridophyte and later gymnospermous plants flourished. The generally mild to tropical conditions with their warm shallow seas were interspersed with Ordovician and Permo-Carboniferous ice ages. Towards the end of the Paleozoic the continents clustered into the supercontinent of Pangea, and increasingly aridity meant the end of the great Carboniferous swamps and their unique flora and fauna. The Paleozoic was brought to an end by the end Permian mass-extinction, perhaps the most severe extinction the planet has seen.
Mesozoic Era
Mesozoic Era
Lasting little more than half the duration of the Paleozoic, this was a spectacular time. The generalized archosaurian reptiles of the Triassic gave way to the dinosaurs, a terrestrial megafauna the like of which the Earth has not seen before or since. While dinosaurs dominated the land, diverse sea-reptiles ruled the oceans, and invertebrates, especially ammonites, were extremely diverse. Pterosaurs and later birds took to the sky. Mammals however remained small and insignificant. Climatic conditions remained warm and tropical worldwide. The supercontinent of Pangea broke up into Laurasia and Gondwana, with different dinosaurian faunas evolving on each. During this era modern forms of corals, insects, new fishes and finally flowering plants evolved. At the end of the Cretaceous period the dinosaurs and many other animals abruptly died out, quite likely the result of an asteroid impact and associated extensive volcanism (acid rain)
Cenozoic Era
Cenozoic Era
With the extinction of the dinosaurs and the end of the Mesozoic, the mammals swiftly inherit the Earth. Archaic mammals co-existed with birds and modern reptiles and invertebrates. The current continents emerged, and the initial tropical conditions were replaced by a colder drier climate, possibly caused by the Himalayan uplift. The appearance of grass meant the rise of grazing mammals, and the cooler drier world allowed modern mammalian groups to evolve, along with other lineages now extinct and a few archaic hold-overs. Among the newcomers were the anthropoid apes that culminated in the australopithecine hominids of Africa. Decreasing temperatures and a polar landmass of Antarctica resulted in a new Ice Age. Most recently, in the blink of an eye geologically speaking, this era saw the rise of Man (Homo erectus, Neanderthal and Cro-Magnon) and use of stone tools and fire, the extinction of Megafauna, and civilization and human activities that have transformed the globe, but at a cost of great environmental destruction.

The "The SEVEN "DAYS" WERE GEOLOGICAL ERAS" is now its own topic, located here. If discussion of such appears anywhere else, prepare to suffer the wrath of Moose. - Adminnemooseus

Edited by Adminnemooseus, : Hide, banner, and note.


This message is a reply to:
 Message 36 by Percy, posted 11-29-2012 6:45 AM Percy has acknowledged this reply

    
kofh2u
Member (Idle past 1411 days)
Posts: 1162
From: phila., PA
Joined: 04-05-2004


Message 45 of 46 (704958)
08-20-2013 9:17 PM
Reply to: Message 36 by Percy
11-29-2012 6:45 AM


Misplaced new topic attempt
......

Edited by kofh2u, : I was trying to propose a new thread, so I am deleting this.

Edited by Adminnemooseus, : Change topic subtitle to "Misplaced new topic attempt"


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