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Asteroid likely caused global fires, which led to extinctions
Watts Up With That? ^ | March 27, 2013 | by Anthony Watts

Posted on 03/28/2013 9:02:58 AM PDT by Ernest_at_the_Beach

From the AGU:

Global fires after the asteroid impact probably caused the K-Pg extinction

example graphic

Chicxulub Crater, Yucatán Peninsula, Mexico – Artist’s Impression Image: University of Colorado

About 66 million years ago a mountain-sized asteroid hit what is now the Yucatan in Mexico at exactly the time of the Cretaceous-Paleogene (K-Pg) mass extinction. Evidence for the asteroid impact comes from sediments in the K-Pg boundary layer, but the details of the event, including what precisely caused the mass extinction, are still being debated.

Some scientists have hypothesized that since the ejecta from the impact would have heated up dramatically as it reentered the Earth’s atmosphere, the resulting infrared radiation from the upper atmosphere would have ignited fires around the globe and killed everything except those animals and plants that were sheltered underground or underwater.

Other scientists have challenged the global fire hypothesis on the basis of several lines of evidence, including absence of charcoal-which would be a sign of widespread fires-in the K-Pg boundary sediments. They also suggested that the soot observed in the debris layer actually originated from the impact site itself, not from widespread fires caused by reentering ejecta.

Robertson et al. show that the apparent lack of charcoal in the K-Pg boundary layer resulted from changes in sedimentation rates: When the charcoal data are corrected for the known changes in sedimentation rates, they exhibit an excess of charcoal, not a deficiency. They also show that the mass of soot that could have been released from the impact site itself is far too small to account for the observed soot in the K-Pg layer. In addition, they argue that since the physical models show that the radiant energy reaching the ground from the reentering ejecta would be sufficient to ignite tinder, it would thereby spark widespread fires. The authors also review other evidence for and against the firestorm hypothesis and conclude that all of the data can be explained in ways that are consistent with widespread fires.

Source:
Journal of Geophysical Research-Planets, doi:10.1002/jgrg.20018, 2013
http://onlinelibrary.wiley.com/doi/10.1002/jgrg.20018/abstract

Title:
K/Pg extinction: Reevaluation of the heat/fire hypothesis

Authors:
Douglas S. Robertson: Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA; William M. Lewis: Department of Ecology and Evolutionary Biology and Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA; Peter M. Sheehan: Department of Geology, Milwaukee Public Museum, Milwaukee, Wisconsin, USA; Owen B. Toon: Department of Atmospheric and Oceanic Sciences and Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado, USA.


TOPICS: Astronomy
KEYWORDS: asteroid; astroid; catastrophism; firestorm

1 posted on 03/28/2013 9:02:58 AM PDT by Ernest_at_the_Beach
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To: SunkenCiv

fyi


2 posted on 03/28/2013 9:03:59 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: All
From the comments:

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Bill_W says:

March 27, 2013 at 4:48 am

And what do you get when you burn things? CO2!!! The demon gas strikes again.

3 posted on 03/28/2013 9:06:31 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: Ernest_at_the_Beach

Probably should outlaw asteroid fires.


4 posted on 03/28/2013 9:06:41 AM PDT by mykroar (Moderation in temper is always a virtue; but moderation in principle is always a vice.-Thomas Paine)
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To: Ernest_at_the_Beach

K-Pg? What was wrong with the widely accepted K-T?


5 posted on 03/28/2013 9:07:05 AM PDT by null and void (If the government is so worried about civil disturbance, why are they working so hard to disturb us?)
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To: Ernest_at_the_Beach

It seems each “scientist” has to have a different theory.


6 posted on 03/28/2013 9:07:09 AM PDT by mountainlion (Live well for those that did not make it back.)
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Theresa says:

March 27, 2013 at 5:19 am

I have heard that it was the Dekkan traps volcano eruption that killed them. Does that create Co2 as well?

7 posted on 03/28/2013 9:09:06 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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AleaJactaEst says:

March 27, 2013 at 5:21 am

Interestingly the only geologist on the paper was the third author. The KT boundary discussion (now I’m showing my age as I prefer the KT monika) is many years old. The related extinction event took several million years and this is shown in the fossil record. Global wildfires would have caused an immediate (in geological terms) fingerprint. One that does not exist in the said record.

8 posted on 03/28/2013 9:10:51 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: null and void

I’ve only ever heard it called the K-T boundary. WTH is this new one for?


9 posted on 03/28/2013 9:12:29 AM PDT by EEGator
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To: All
And in the spirit often seen on FR....:

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darwin says:

March 27, 2013 at 5:42 am

I think they’re wrong. Recently scientists have uncovered fossilized SUV’s and coal fired power plants. The evidence is mounting that Global Warming controls everything.

10 posted on 03/28/2013 9:12:45 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: mountainlion

How else could one get public monies?


11 posted on 03/28/2013 9:13:14 AM PDT by EEGator
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To: All
Back to serious.....:

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jim2 says:

March 27, 2013 at 5:44 am

You can see a CO2 spike ~ 66 million years ago in this stomata study. This study shows CO2 much higher in the past than now.

http://www.sonoma.edu/users/c/crocker/516-2011/300myr%20profile.pdf


12 posted on 03/28/2013 9:14:31 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: EEGator

I’m guessing people who deal with deep time are jealous of historians who affect BCE...


13 posted on 03/28/2013 9:15:04 AM PDT by null and void (If the government is so worried about civil disturbance, why are they working so hard to disturb us?)
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Micula says:

March 27, 2013 at 6:02 am

A layer rich in carbon was recorded from the classic K/T (K/Pg) site at Stevn’s Klint in Denmark. It was referred to by Hans Joergen Hansen (Univ. Copenhagen) as the “grey chalk” and has been used by some researchers as evidence of the post impact fire storm. Detailed sedimentological analysis shows that the carbon content includes 1-2 micro diameter hollow graphite spheres, known only from volcanic glasses. The depositional period of the “grey chalk” has been calculated by H.J. Hansen as approximately 600 thousand years. As he once said on a field excursion, “If we could find the wood that burns that long, then the energy problems of the world would be solved.”

14 posted on 03/28/2013 9:16:46 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: mykroar
Probably should outlaw asteroid fires.

Indeed, or legislate earth an asteroid free zone. Never happen again.
15 posted on 03/28/2013 9:16:54 AM PDT by ZX12R
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To: EEGator; null and void
Hmmm....see #14.

Maybe a clue.

Probably a paper somewhere.

16 posted on 03/28/2013 9:18:54 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: Ernest_at_the_Beach

this whole thing about how a one mile wide asteroid can somehow send dust into the air and cause a world wide ice age and now cause a planetary fire is such total crap


17 posted on 03/28/2013 9:20:30 AM PDT by Hammerhead
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To: Ernest_at_the_Beach; null and void

I’ll see if I can find the origin of the change.


18 posted on 03/28/2013 9:23:29 AM PDT by EEGator
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To: Hammerhead
Isn't it a matter of size?

More:

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Hypothermania says:

March 27, 2013 at 6:22 am

DaveF says:
March 27, 2013 at 5:46 am
So what killed those dinosaurs that lived in the sea?

Burning trees caused CO2 levels to increase, which caused sea levels to rise dramatically and they all died from vertigo.

19 posted on 03/28/2013 9:24:20 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: All
Good one:

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CodeTech says:

March 27, 2013 at 6:26 am

They also show that the mass of soot that could have been released from the impact site itself is far too small to account for the observed soot in the K-Pg layer.

Sure. The models show that. However, what other possibilities exist?

First, look at the current understanding of the Chicxulub impactor. It appears to have been about 6 miles in diameter, and left visible rings at 40 miles and 110 miles in diameter. An exceptionally thick layer at 4200 feet deep was part of the discovery, and there is displaced material that indicates a “kilometers high” tsunami, which is to be expected from such a powerful impact. Imagine that volume of water washing away in all directions, and be glad that nothing like this has happened recently. It seems likely that any combustible forest for a long way away would have been stripped bare and carried away.

Second, consider the incredible energy that has just been expended on the crust, sending ringing shock-waves around the planet like a bell had been rung. Any weak spot would soon be volcanic, and who’s to say just how much of the mantle was exposed? Was the crater a gaping, smoking hole for years afterward? We’ve seen just how much material is ejected from a single volcano (Pinatubo comes to mind, and Mt. St. Helens), just multiply that by an unknown but large number. The entire planet was likely blanketed by soot and ash as a direct result, and possibly for decades.

Third, we’ve now seen the Chelyabinsk event, recorded on video from multiple angles. That was a very high relative speed event, and I didn’t see any evidence of ground structures bursting into flames. Ejecta from the Chicxulub impact that cleared the atmosphere and came crashing back would not have the same kind of relative speed, thus less chance of igniting the forests (which were probably washed away).

I like playing “imagine if” games as much as anyone, but the conclusions I’m reading here seem like they’re all on the outside of probability. Nothing seems to take away the most likely current theory, that the extinction event was caused by dramatic and rapid cooling caused by the impact itself, not giant forest fires. Although I don’t doubt there were fires from the impact, and it’s nice that they measured all the soot.

One thing IS certain… we can theorize and hypothesize and imagine all we want, but NOBODY knows for sure exactly what happens when an impact of that magnitude occurs. And if we’re lucky, we never will.

20 posted on 03/28/2013 9:25:43 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: Ernest_at_the_Beach; null and void

It seems as if it was changed by these people:

http://en.wikipedia.org/wiki/International_Commission_on_Stratigraphy

http://stratigraphy.org/


21 posted on 03/28/2013 9:26:26 AM PDT by EEGator
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To: null and void
I’m guessing people who deal with deep time are jealous of historians who affect BCE...

Oh, that Before Christian Era thingy? (8^P)

22 posted on 03/28/2013 9:31:36 AM PDT by Smokin' Joe (How often God must weep at humans' folly. Stand fast. God knows what He is doing)
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To: EEGator

Thanks.


23 posted on 03/28/2013 9:34:19 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: Ernest_at_the_Beach

Gigantic Jenga Busters make such a mess.. not to worry, no one is left to clean up afterwards


24 posted on 03/28/2013 9:35:37 AM PDT by NormsRevenge (Semper Fi)
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To: Ernest_at_the_Beach

Anytime. I owe you some links anyway. :)


25 posted on 03/28/2013 9:37:29 AM PDT by EEGator
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To: null and void

“Cretaceous–Paleogene (K–Pg) boundary (formerly known as the K–T boundary) is a geological signature, usually a thin band, dated to 66.0 Ma (million years) ago.[1] K is the traditional abbreviation for the Cretaceous period, and Pg is the abbreviation for the Paleogene period. The boundary marks the end of the Cretaceous period, which is the last period of the Mesozoic era, and marks the beginning of the Paleogene period of the Cenozoic era. The boundary is associated with the Cretaceous–Paleogene extinction event, a mass extinction, which is considered to be the demise of the non-avian dinosaurs.[2] The boundary layer was once known as the K–T boundary, but Tertiary has been deprecated as a formal time or rock unit by the International Commission on Stratigraph”

http://en.wikipedia.org/wiki/K%E2%80%93T_boundary


26 posted on 03/28/2013 9:39:54 AM PDT by TheThirdRuffian (RINOS like Romney, McCain, Dole are sure losers. No more!)
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To: TheThirdRuffian; EEGator
An International Commission on Stratigraph

Of course!

27 posted on 03/28/2013 10:04:52 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: Ernest_at_the_Beach

An absolutely necessary International Commission. What would we do without them?


28 posted on 03/28/2013 10:07:14 AM PDT by EEGator
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To: Hammerhead
It was 7 miles wide. Do the math. That's a whole double pee-pot full of energy.

Roughly the same as setting off 100,000,000,000,000,000,000 tons of TNT. Count dem zeroes, that's 100 million megatons.

Add to all that energy dumped instantaneously into the atmosphere and near space the intrinsic heat of the now exposed yellow-hot mantle.

As an added bonus, it was an edge of a shallow sea strike. Where does the ocean go? Well, after the big splash, it tries to refill the crater.

Imagine that, pouring an ocean of cold water into a 10,000 square mile 2400°F furnace. That's a recipe for steam-cleaning half a planet!

Do you think that all that water rushing into the crater would be crystal clear, or do you think it might be full of silt and sand scoured from the sea floor? Would the grit passively settle to the crater floor or be blasted into the are with a 100 mile wide jet of live steam?

How high would world humidity be after the month of so of an entire ocean finally won the battle for the crater floor?

The atmosphere would be utterly saturated with water vapor, thick clouds and dust. Torrential rains where it's warm enough, sleet, hail, and snow everywhere else. And with that unbroken cloud cover reflecting the sun's heat back into space, the warm areas are pretty small.

Then things get worse. The Yucatan was covered by about a mile and a half of limestone, nature's carbon dioxide storage medium. the heat and pressure of the impact broke the bonds holding the carbon in the calcium carbonate, besides a supervolcano of live steam, the blast released a vast cloud of that most evil of chemicals, CO2!

I'll get to the bad part shortly.

Limestone also contains vast quantities of sulfur (ever drink well water in Florida?) That sulfur gets vaporized and oxidized and hydrated into sulfuric acid.

Now the bad part.

All the air within 300 or so miles of the impact was heated and shocked and zapped by ultraviolet and electrical discharges so hard that most of the oxygen and nitrogen were ionized, generating vast quantities of oxides of nitrogen, which combined with all that water vapor to form nitric acid.

All that rain and snow? Full of carbonic acid, sulfuric acid and nitric acid.

All in all, it was a pretty bad day to be a dinosaur...

On the bright side, after a couple years of dirty rain and snow, the cloud cover clears. Now all we have is an atmosphere with a huge residual eeeeevil CO2 concentration.

Things get warm and dank. The land has a fresh new layer of mineral rich ejecta, and more minerals have been freed up by all the acids unlocking them from solid rock. The atmosphere is full of that essential plant nutrient, CO2.

It would have been a virtual garden of Eden for anything that managed to survive.

29 posted on 03/28/2013 10:12:55 AM PDT by null and void (If the government is so worried about civil disturbance, why are they working so hard to disturb us?)
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To: null and void

so basically a stone only 7 miles long destoys and entire planet.

yeh right.


30 posted on 03/28/2013 10:26:18 AM PDT by Hammerhead
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To: Hammerhead

so basically a bullet only .22 inches wide kills an entire human.

yeh right.


31 posted on 03/28/2013 10:33:45 AM PDT by null and void (If the government is so worried about civil disturbance, why are they working so hard to disturb us?)
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To: null and void

It’s like the K-Pg13 but with less profanity.


32 posted on 03/28/2013 10:37:55 AM PDT by Tijeras_Slim
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To: NormsRevenge
Jenga Busters?

Hmmm....OK....adding to my dictionary...LOL!

33 posted on 03/28/2013 10:41:03 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: null and void
Mice rendition....makes plausible sense.

That is a huge impact....certainly gonna change things.

34 posted on 03/28/2013 10:49:30 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: Ernest_at_the_Beach

Forgot to check the spelling....Mice=> Nice...


35 posted on 03/28/2013 10:50:45 AM PDT by Ernest_at_the_Beach ((The Global Warming Hoax was a Criminal Act....where is Al Gore?))
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To: Ernest_at_the_Beach

Mice works. They survived.

I did leave out the part about the fires. Flaming debris would arrive in distant locations well before the new weather pattern shows up.

Essentially it’s like a billion red hot intercontinental ballistic missiles screaming in around the globe, with the water bomber fleet slouching in later for clean-up.


36 posted on 03/28/2013 11:02:19 AM PDT by null and void (If the government is so worried about civil disturbance, why are they working so hard to disturb us?)
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To: Hammerhead

The planet is fine.

The life living on the thin crust of the planet, which life can only survive in a very narrow temperature and climate band? Almost all dead.

Not hard to believe, at all.

In fact, from this Christian’s perspective, an asteroid impact is predicted in Revelations called “wormwood” which is a “star” that falls from the sky and causes basically all the same crap the scientist have talked about kiling the dinos.


37 posted on 03/28/2013 11:16:57 AM PDT by TheThirdRuffian (RINOS like Romney, McCain, Dole are sure losers. No more!)
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To: TheThirdRuffian
Indeed.

Such an impact would ring the planet like a bell.

Any fault line with enough tension built up would be shaken loose into an earthquake, "mountain and island were moved out of their places".

Earthquakes and shocks would disturb aquifers, cracking rock and exposing the waters to fresh supplies of salts and soluble minerals, "making a third of the waters bitter", perhaps?

Once the eject starts reentering the earth's atmosphere what would that look like? Like "the stars of heaven fell unto the earth"!

What survived Chixulub? The very creatures the lived or nested underground, that "hid themselves in the dens and in the rocks of the mountains".

What would the mushroom cloud/ejecta blanket look like as it swept high over an observer? Like a scroll rolling over the heavens, maybe?

See my description at post #29. Does my description of the volcano of steam sound even a little bit like:

And he opened the bottomless pit; and there arose a smoke out of the pit, as the smoke of a great furnace; and the sun and the air were darkened by reason of the smoke of the pit.
Yeah. A disaster of quite literally Biblical proportions.
38 posted on 03/28/2013 11:58:57 AM PDT by null and void (If the government is so worried about civil disturbance, why are they working so hard to disturb us?)
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To: null and void
"...Mice works. They survived..."

Mammals survived—a Good Thing—huh?

39 posted on 03/28/2013 4:48:10 PM PDT by Does so (Progressives Don't Know the Meaning of INFRINGED...)
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To: EEGator

Cretaceous - Paleogene (Paleogene corresponds to Paleocene + Eocene, the 1st two epochs of the Tertiary.


40 posted on 03/28/2013 5:00:20 PM PDT by rfp1234 (Arguing with a liberal is like playing chess with a pigeon.)
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To: Ernest_at_the_Beach; 75thOVI; agrace; aimhigh; Alice in Wonderland; AndrewC; aragorn; ...

Thanks Ernest. Just the energy release from the impact (and leaving aside consideration of any other of its effects) would be sufficient to raise the global atmospheric temperature -- at first -- by degrees (somewhere in double digits). Even if nothing else happened, some species would succumb just from the temperature increase. The fires started by both the flash (over hundreds of miles in all directions) and hot ejecta (thousands of miles) did do damage, but the crud that went straight up, then out, blanketed the Earth with an opaque cloud of dust and soot in perhaps 90 minutes, and the blanketing lasted probably for years; so after the temporary increase in temperature, the lack of sunlight reaching the surface slowed the hydrologic cycle (no rain or snow for years), and the basis for the food chain (the plants) went dormant or died from lack of light and water.


41 posted on 03/28/2013 9:49:39 PM PDT by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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To: Ernest_at_the_Beach; SunkenCiv; blam; All

I think another factor in the mass extinction could have been destruction of the ozone layer and radiation burning and cancer to animals without thick fur/feathers, or nocturnal or underground habits. Note that the reptile survivors were snakes, alligators, turtles, etc. which all tend to use burrows or are small and can hide. Birds and mammals, feathers, fur, live in trees or jungles, or hide in burrows or were small.


42 posted on 03/28/2013 10:13:50 PM PDT by gleeaikin
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To: gleeaikin

Burrowing species had an advantage over other land creatures because of availability of water, soil critters (insects, worms, etc) and cover (all foliage vanished); marine species were mostly selected by size.


43 posted on 03/29/2013 5:20:19 AM PDT by SunkenCiv (Romney would have been worse, if you're a dumb ass.)
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