posted on Dec, 21 2011 @ 10:29 PM
First of all, you need to get some data on the time scale.
* The solar system was basically "hot lumps of rock" until around a little less than a billion years ago. Yes, that means Mars, too. For quite
awhile after, it was "cooling lumps of rock colliding." During the last part of the era, a collision causes the moon to separate from Earth.
* Earth didn't actually cool off and have water and continents (become habitable) until 600 million years ago or so.
* First fossils show up 500 million years ago.
* modern atmospheres don't show up until much later.
All civilizations leave a lot of traces. Advanced civilizations leave a LOT of traces -- from precision cut mines to garbage heaps, roads, modified
land area (water storage, crops) both above and below ground. Layers of rock and soil show intrusions (someone dug foundations for something); crops
modify the land.
Domesticating things produces huge change in species in very very short time periods (5,000 years or less.) Look at the changes in the dog and the
horse and the cat within the past 4,000 years... likewise changes in any other animal we domesticated. It's all been very sudden and very extreme
(from tiny pot bellied pigs to huge market ready hogs.)
Advanced industrialization also means people lose and abandon technology, and durable tech like that would last a very long time. Go to a city
sometime, and look around at what people drop or lose... and think of thousands of years of people (or whatevers) dropping and losing things and
City sites are very interesting and messy from an archaeologist's standpoint. A very old city would be evident from flattened planned landscapes
(like city blocks, etc) with a lot of surrounding land heavily modified (crops, landing ports, fishing ports, etc) and landfill/junk piles for
abandoned and nonfunctional technology.