Joey_Bose
Joined: 26 Aug 2006
Posts: 7
|
 Posted: Sat Aug 26, 2006 3:09 pm |
 |
|
The question about previous civilizations inhabiting Earth ties into ponderance over life on other planets. Basically, scientists define life as carbon-base, respirating, consuming and excreting beings. We know nothing other than the life forms on Earth, so we have no ground to speculate on life forms on planets that don't have the atmosphere nor conditions of this planet. There very well could be life forms that don't need Light, Oxygen, or Carbon Dioxide to survive, but there is no scientific evidence to support such speculation.
Having clarified that, back to the question. Could there have been a past civilization that inhabited Earth, but that we have no evidence of. In the opinion, no (remember, that this is only a hypothesis). The stable, homeostatic conditions that we have come to know and enjoy were not present during the turbulent phase of Earth's creation. Beings based on our molecular and physiological structures could not survive in the hostile conditions. Oxygen was released fairly recently in Earth's geologic time, from volcanoes that introduced most of the elements now in our atmosphere. Now, you may wonder , "what about beings that are not based on our physiology?" This is a valid question, but again, there is no evidence to support the conclusion that life is based on something other than carbon (like silicon, for example, which is very similar to Carbon on the atomic level).
It would be incredibly naiive to assume that life could not or has not existed on this planet or any of the other billions in the vacuum of space-time, but according to our present definition of life none could have existed on our planet previous to our inhabitance.
_________________
Joey Bose
BoseDesigns.com - Affordable Web Design for the Small Business |
|
