Fossils show flying reptiles were 'size of a small aeroplane'

The Daily Telegraph ^ | September 9, 2005 | British Association Festival of Science

[kennyboy509]

Uhh!

1953 When i wuz born,

I member seeum out my winder.

[null and void]

Those limits are set by air density.

Denser air can support more weight for a given wing surface area.

Denser air also implies more oxygen, those suckers were effectively turbocharged!

[ClashOnBroadway]

Not to threadjack w/ a non-dino comment, but are you (or your friends) thinking of the Piri Reis map?

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

Not Chinese (it's said to be made by a Turkish admiral), but it supposedly comes from the 1500s and it depicts a coastline for Antarctica sans the covering sheet of ice.

/back to lurking

[GSlob]

Atmospheric composition and pressure have not changed that much over last 300 Myr. Several atmospheres of oxygen would have killed the plants and screw up hemoglobins in dinosaurs. Nitrogen is inert, and has not been lost or sequestered at appreciable rate to account for a large lost atmosphere. As for carbon dioxide - if there were so much more of it as to have atmospheric pressure doubled or tripled, THAT would be the global warming - and would have the dinosaurs (and everything else) well done without any large asteroid.

[keithtoo]

Yes I have heard of giraffes, and I have read that the distance between a giraffe's heart and its brain - when it's head is fully extended upwards - demands about as much blood pressure as a heart can be expected to produce without bursting. I have read that anything beyond that would be physically impossible.

[Dashing Dasher]

Okay.... ummm... okay....

[King Prout]

nope - not thinking of the "Queen Maude's Land" coastline on that map, though that one IS pretty damned interesting in itself and MAY have formed part of the basis for the maybe-mythical Chinese map.

[null and void]

Source please?

[Publius6961]

If you haven't done so, try to get a copy of a book from about 35 or so years ago, UFOs, The Eye and The Camera.
I found a used copy at Amazon not too long ago.

[Max in Utah]

Another theory that's really wild is that the picture is an anomaly and that while it was once part of our 'timeline' - that is, the event did happena nd a photo was taken and published in books, etc, but it's evidence of some kind of temporal mishap, and that timecops from the future went back in time and either stopped the event from happening, stopped the picture from being taken, or confistacted all photos/negatives early in its history such that it was 'erased' from our timeline, yet the mind being the amazing thing that it is, those who saw the photograph later in history (say the 1970s) 'remember' it, and when the timecops went back in time and averted the photo being taken, the picture and accounts 'vanished' from future accounts of the story.

Whew, that's some sentence!

Hope you see a pair o' docs... soon :)

[Wiseghy]

"Atmospheric composition and pressure have not changed that much over last 300 Myr. Several atmospheres of oxygen would have killed the plants and screw up hemoglobins in dinosaurs. Nitrogen is inert, and has not been lost or sequestered at appreciable rate to account for a large lost atmosphere. As for carbon dioxide - if there were so much more of it as to have atmospheric pressure doubled or tripled, THAT would be the global warming - and would have the dinosaurs (and everything else) well done without any large asteroid."

Excellent point.

There is a GREAT deal that they can deduct from the fossil and geologic record. Some have called it "Foresic Paleontology" (think CSI for Dinos).

Nonetheless, theories are presented and discussed. The evidence eventually dictates the truth.

[null and void]

The only figure mentioned on this thread is "30% or twice the density that we have now" more air pressure.

No one else is talking about "Several atmospheres of oxygen"

Nitrogen is not immune to being blasted into space by giant meteor impacts, and being slightly lighter than oxygen, it would be swept into interstellar space by solar wind at a very slightly higher rate. This means that 300 mya the percentage of O₂ was a bit higher, maybe pushing 25%?

Let's take underscoreJim's figures at face value. (Although I frequently and vehemently disagree with him on the robustness of human designed systems).

Today the partial pressure of oxygen is 20% of 760 mmHg or about 150 mmHg.

300 mya the partial pressure of oxygen was 25% of about 1500 mmHg or roughly 375 mmHg.

Every lung full would have over twice the available oxygen.

All other things being equal, a critter could burn twice as much fuel, and generate twice the power it could today.

Add to that the available lift due to the denser air is 4 times higher (It goes as the square of the density IIRC) and rilly big critters could fly!

Nobody KNOWS what the environment was that far back. There's no way to verify it.

Bubbles trapped in amber have consistently shown higher oxygen content than today's air.

[null and void]

Ping to post #72

[null and void]

Air bubbles, amber, and dinosaurs

[jokar]

You don't say !! Would you post some photos please.

[HitmanLV]

Hey, this stuff is intense!!! :-)

[jokar]

Oregon State University professor Octave Levenspiel, who presented his theory .

It's a theory! Something from his imagination you guys really crack me up.

[claptrap]

Bone fragments and footprints? Footprints in what? And why did they die out? So if the earth is millions of years old
its satilite the moon must be millions of years old, and the accumulated cosmic dust on the moon would be twenty feet thick, thats why NASA scientists put those huge pads on the feet of the lunar lander when they got to the moon
the dust was a mere few inches thick. Another thing which doesnt make any sense is why if oil is made of these "fossils decomposed flesh"
how do they get buried so deep in some places and in others they are close to the surface?

[HitmanLV]

I recall reading in my research into the macabre, the strange, and the BS, that there is some record of a prelunar history - that is, a record of a time before we had a moon. Go figure that one out!

[Ichneumon]

[Nobody KNOWS what the environment was that far back. There's no way to verify it.]

Bubbles trapped in amber have consistently shown higher oxygen content than today's air.

Higher (or lower) atmospheric oxygen values also have predictable chemical effects on minerals that are deposited over time, and by studying ancient layers of minerals, etc., it's relatively straightforward to determine how much oxygen was present at the time they were laid down.

There are actually *many* ways to verify (and cross-check) atmospheric composition at various eras in the past.