Not that I'm learned about the subject but I have always found it hard to swallow that a cataclysmic event wiped out the dinosaurs. I'm more of a mind that a lack of a viable food source led to the larger dino's demise and the smaller ones just evolved into the common day bird. Natural selection and all that rot old Charles.

Well let's see.

During the Permian age of dinosaurs, the earth's land masses were all bunched together forming Pangaea (ca. 250MM years ago). The Great Permian Extinction is dated to that time frame. A fairly popular theory for this Extinction is that a series of large cataclysmically sized asteroid collisions over a period of a few million years caused the ejection of highly acidic gases from the beneath the earth's surface to build up in the atmosphere and in the seas causing a huge change in the chemical eco-balance. Pangaea started breaking apart about 180MM years ago (MYA), at which point N. America / EurAsia started its separation from Gondwana (S.Amer, Africa, India, Australasia).

During the Cretaceous (150 to 65 MYA) the land masses were not yet totally separated away from each other as it is today.

Considering the greater proximity to each other that the continents had when the
Chicxulub Crater is believed to have been formed ... ca. 65 MYA ... it is possible that the effects of such a blast and its ejecta may have had a better shot at blotting out enough sunlight and contaminating the ecosystem with toxic gases to cause a die-off of the larger life forms.

im to drunk to understand any of this so ill post my view on this when iver sobered up and not press backspace every 3 letterss kkkkkkk?

Knowing next to f*ck all about said subject I'll just reply with a "Hrmm" and a "perhaps"

mustang you must know a lot then

elegant, but afaik there are two areas of evidence for an impact-driven extinction that don't stand up.

1. global firestorms - the evidence simply isn't there. Whilst there are fossil ash deposits around the crater for several thousand miles, there's no repetition of this evidence worldwide. But the accepted picture of an asteroid wiping out the earth has burning ash falling from the sky across the globe, so where's the ash?

2. acid rain - supposed to destroy ecosystems and disrupt the food chain, cutting off plant and small animals from larger predators. but the overall global survival of frogs, which are very sensitive to chemical changes as caused by acid rain, contradicts the acid rain hypothesis. again, the classic hypothesis is that the asteroid landed in a bed of undersea gypsum which when violently ejected under heat to the upper atmosphere would produce worldwide acid-rain, and the Yucutan Chicxulub impact 65mya was in a bed of gypsum - but where's the acid rain then?

so two main planks of the killer-asteroid theory are lacking in evidence, with no adequate alternative explanation to justify them. Local devastation certainly but no clear signs of global impact devastation apart from the K-T layer istelf....

Well certainly, were frogs old enough to date back to the Permian Age, I would agree that they would debunk the great Permian Extinction theory fairly handily.

Frogs date back to about 190MYA.

Do we know for sure what's killing the frogs today? I didn't think it was established as to whether it was acid or other chemicals and if other chemicals, especially, are they ones that would be the result of other than artificial human processes?

The extent of the extinction in the Cretaceous, while great, wasn't as pervasive as the Permian so it need not have necessitated the ecologically calamitous chemical imbalance that is ascribed to the Permian one.

I'm not sure about ash as we know it being the necessary trace to be found in the soil to support firestorms much like not all volcanic eruptions result in an "ash" layer. The KT layer could be what is left of such "ash" as it were, after some 65MM years of sedimentary action.

Might it not be possible that the asteroid impact, and the resulting effects of its atmospheric ejecta were just sufficient enough to trigger a die off over a geologically short period of time in dinosaurs due to an inherent organic weakness that made them susceptible to the ecological conditions?

"The KT layer could be what is left of such "ash" as it were, after some 65MM years of sedimentary action."

as I understand it, it isn't. iridium and ejecta, but not much in the way of ash. Of course, I'm reading someone else's work, not looking for myself. This is always the problem with using secondary sources.

Edited by - Tawakalna on 9/14/2007 12:18:42 PM

some people belieeve in creation, and think thats all a load of BS concocted my scientists, but i dygress (SP?)

i was raised with creation, and while it has its own scientific quarls, so does a giant asteroid(as proved by this topic...) ive always thought that people should be free to believe what they wish. I wont badger you with creation, if you dont bug me about evolution.

while this isnt tied directly into this argument, it does have some bearing, as the bible states that the world is a few hundred thousand years old, in direct conflict with the fossils that date to 250 mill years ago... IF an asteriod (or mutliple asteroids) did cause mass extinctions, evolution would play a part, in direct conflict to creation.

To throw a monkey wrench into all of this, it could be argued that creation and evolution are not mutually exclusive. Just because I created something, does not mean that what I created could not evolve on its own at a later date.

Not sure if all this is making sense, but this is my .01c worth...

007

well it wasn't really my intention for this thread to become an evolution v. creation debate, as those are remarkably unproductive and rather fractious. The two camps are diametrically opposed and very hostile to each other, and I try to avoid such discussions as they are premised upon a false dichotomy (as is, sadly, so often the case.) On a personal note, I've never had any problem accepting that God created the universe and everything in it and ordered Nature according to His will, and that the Universe (and therefore the Earth) are as old as Science says that they are.

I've often been criticised for having rather conservative moral standpoints on many issues discussed here and for my beliefs in the afterlife and Day of Judgement (and so forth) but I really don't see how belief in a deity of creation and the scientific analysis of natural phenomena are mutually incompatible

Edited by - Tawakalna on 9/14/2007 1:42:16 PM

uhm, God abhors a naked singularity? - meh, weak i know.. i feel dwarfed in this thread

i don't really care what killed the dinosaurs, because i'm not related and knowing wouldn't mean a thing - dinosaurs did not have tools, or brains, so anything you could learn there would only be helpful in the application of post-apocalyptic ecology - not my field of interest really...

P.S. Jesus put dinosaur bones there to make grammar school less boring, and to give the morally uptight something to complain about besides other people's behavior

Life is precious and God and the Bible
(Mr Show SE4EP1 reference)

Edited by - Cold_Void on 9/14/2007 5:39:24 PM

my post was not an attempt to create a creation vs. evolution, i was just stating some possible scientific/theological issues with the asteroid topic.

like i said, and as taw stated, they do not have to be mutually exclusive...

007

i don't really know much about history that far back, but i do want to know how Esqys computer (Typhon is it?) survived whatever calamity claimed the Dinos

Edited by - Aod2 on 9/14/2007 9:53:08 PM

Is there any particular reason why you are recycling Taw's equally antediluvian jokes AoD? Have you suddenly become environmentally-conscious (metaphorically speaking)?