Moontanman

Michel, as I said before, all things being equal a large planet will have stronger gravitational pull at the surface than a small planet, you keep trying to change the arbitrarily parameters to suit your self. High gravity would mean smaller animals in general due to the cube square law, low gravity would allow for larger animals. Yes it is possible to conceive of a larger planet with less gravity, a 24,000 mile in diameter planet made of ice would not have as high a gravity as as 24,000 mile planet made of iron but you are only trying to wiggle out of being wrong and you know it. BTW, a larger Earth with the same mass???? Care to add to add a mechanism to that large steaming pile of hot male bovine excrement?

The main thing to remember is that the disaster that wiped out the dinosaurs severely affected the entire planet. http://en.wikipedia.org/wiki/Cretaceous%E2%80%93Tertiary_extinction_event

I am not an engineer but I worked with engineers for much of my career with DuPont and i have seen the very thing you are showing in the pics with bolts that "appear" to actually be the same bolts we used in high pressure very hot (300c) polymer pipes. The bolt always comes out like that, you can tell by the lack of damage to the threads that the bolt was not twisted off, that would have broken it above the threads. It is entirely possible that the bolt may have failed due to inherent flaws that made the bolt break when heated (we used them at 350c) and torqued (100fp). We never knew the bolt was broken until we removed the bolt but we were far more likely to see this in manifolds that had been allowed to cool to room temperature after being bolted with hot bolts when the pipes were also very hot. . Oh yeah, one of the studies showed the number of broken bolts went up when we bolted cold bolts into hot manifolds as well, it's been a long time, sorry if it's not helpful.

I agree with csmyth, I would like to see how rearranging the mass of the earth would result in a different gravitational pull at the surface.

I'm sorry Marat, but what does the Coelacanth have to do with the extinction event that caused the deaths of the marine reptiles? No one says everything died at the KT boundary, some animals did survive, I gave an example, sea turtles, there are many more that did survive but not any of the marine reptiles other than the sea turtle.

Either I don't understand what is being asserted or my personal experiences put me somewhat outside the bell curve on this one...

Ok, I didn't understand what you meant, I would have to agree with you that.

There were no marine dinosaurs Peon, but the marine reptiles often characterized as dinosaurs became extinct at the end of the Cretaceous (the ones that made it that at least to the Cretaceous) died off due to the collapse of the marine food chain, the K/T extinction had a profound influence in the sea as well as on land and many marine species both microscopic and macroscopic became extinct as well. Sea turtles are thought by some to be the sole remaining members of the marine reptile groups.

I gave you some insight, you rejected it in favor of your intuition, I never said that you were silliness personified I said your idea that intuition trumps the cube square law is silliness personified: my exact words

Lemur, are you really trying to equate the likelihood of the existence or lack of existence of something with the number of people who believe it or the strength of their conviction of it's existence?

I am pretty sure the dream image comes from being a toddler and being flogged by a banty rooster and in the same time frame a snarling little dog that was also in the yard.

Ummm.... No, the distribution of the mass of the earth from the surface would make no difference in the gravitational attraction at the surface. If you were suspended 4000 miles above the surface of an Earth mass black hole you would still feel 1g.

WHAT! Who says?

One thing that limits life on the Earth is the availability of Nitrogen in the form of nitrates. Nitrogen fixing bacteria are slow and limited, we have to make huge amounts of nitrogen fertilizers to help our crop plants grow. Would a planet with a higher atmospheric pressure (as suggested by realitycheck) allow for more efficient nitrogen fixation and more life?

Yes, like many ideas taken to it's extreme your idea and the fictitious story used to promote it is indeed absurd as is your method of debate, merely waving your hands and saying something cannot be true because of your intuition is not science or even debate, it is just silliness personified.

Yes, i do understand that concept, life in the desert seems to be perfectly suited for life in the desert but we can imagine a habitat less restrictions that would be better for life in general even if it wouldn't be better for desert life. Could the puddle be deeper or broader to hold more life? What could be changed to allow life to proliferate even better than current conditions. Realitycheck's idea of more air pressure seems like a good start, would that result in more life all by it's self?

Great info stringjunky, feed back loops are a big part of why the Earth is the way it is but how does the idea of ice being part of the feed back account for long periods of time with no ice caps at all? Our atmosphere is also bad for many things with billions of years of evolution as well, your statement makes no sense. Can you back that up or is it this another one of your misrepresentations of reality? It feels like? What does this have to do with the OP?

I honestly do not see how sympathy can apply to a scientific discussion but if you insist on feeling sympathy for me give it your best "feeling" I guess.... How so? http://en.wikipedia.org/wiki/Square-cube_law Agreed Agreed There is, it's called the cube square law, and yes it applies to gravity as well... No, the cube square law would prevent a "King Kong" I respectfully suggest you have no idea what the cube square law is or how evolution works. I have repeatedly said that a small planet would be expected to have larger organisms than a large planet (all things being equal) due to the cube square law, so far all you seem to be doing is baiting me by saying inane things that make no sense in regard to reality.

I see no reason to assume that life and or evolution has a tendency to evolve intelligent life or to have any real direction. Yes, that is what I am getting at, can we conceive of conditions being better than they are here on the Earth, would a thicker atmosphere do it alone or are there other things that could be better? That is a very good analogy but is there a limit to what this "active homeostatic management" can do with the limited resources of the Earth that it would do better with more "resources"? What would those resources be, or what resource would be the limiting factor to life on the Earth might be a better way to put it.

Most people think of the Earth as paradise for life, so much life and so diverse, and when you look at the planets of the solar system all you see is planets totally hostile to life. But is the Earth really all that perfect or is the Earth the equivalent of a desert with a mere shadow of the life that would be possible with more of everything the Earth already has. Life in the desert scrub land of the South West US has an amazing variety, if you had never seen a tropical rain forest or anything but those desert scrub lands you might come to the conclusion that those scrub lands are perfect for life, from giant cacti to annual flowers that carpet the landscape in color this "scrub land" can be full of life and if you only had this place as an example of an ecosystem you might think too much water would be a bad thing since many desert plants are killed by too much water. But lets apply this to a planet... Could another planet be better than the Earth for life? Even complex life? Is the Earth as good as a planet can be for life? (within natural limits) Or is life on Earth adapted to and limited by the Earth? Lots of parameters to play with but what would result in the Earth being even more hospitable to Life than it already is?

Care to elaborate on that? Your story is cute, i remember it from childhood as well, but the cube square law would suggest you are mistaken, a large planet implies stronger gravity, the cube square law would suggest even further that on such a planet animals would tend to be smaller due to the strength of materials and the weight of them as well. This is the reason the idea persists that the Earth must have had less gravity way back "when ever" because this would have allowed for larger but less heavy animals. But as i stated in an earlier post, low gravity, like on Mars, means no need for strong bones, flying would be much easier and the birds could be enormous... that is of course if a small planet could maintain a thick atmosphere, low gravity worlds would have little air, no magnetic field, no plate tectonics ... much like Mars, the case for low gravity but large animals hinges on a pretty big if....

You are the one who brought Mr Stojanowski's idea into this and yes for gravity to be different then than now would require the laws of physics to have changed.

I'm not sure it even qualifies as speculation.... So we look at the possibility that the laws of physics was different 250 million years ago as a mechanism to explain large creatures instead of thinking that dinosaurs are different than mammals and seem to do large body types better? Dinosaurs were not just large reptiles or scaly mammals, they were as different as oranges and strawberries from mammals. Dinosaurs suppressed the existence of mammals, they had superior attributes that mammals lack and mammals have not had a similar length of time to evolve past those limitations. http://www.dinoextinct.com/page12.htm Your own link describes the reason for this gigantism to be the morphological differences between mammals and sauropod dinosaurs, (as I have pointed out) not a change in the gravitational field of the earth... it is important o point out there are no mammalian equivalents of sauropod dinosaurs to start with, to make a fair comparison you would first have to find a mammal with a long neck and tail, bird like respiratory system and hollow bones. No such mammal exists nor do mammalian equivalents of theropods exist either. The two groups of animals are simply not easily compared.

I think it's necessary to bring up thorium reactors as well, uranium is not the only fissionable element in the earth's crust and there is lots of thorium. Breeder type reactors give us leeway to use lots more than U-235.

Neg rep rarely if ever helps anything, if I give neg rep i usually feel quite guilty about it due to knowing my own inadequacies, but once a thread gets stupid and real debate ends i think neg rep points that out to people who wander by and might think that the idea of some totally implausible assertion is a great thing and since he doesn't know any different neg rep seems to be indicated but I do like to give pos rep as much as possible.