I thought it might be interesting to assemble a list of conclusions that creation science has drawn about the world as it was in those first days of creation. Surprisingly, I haven't come across a summary of creation science research before, so this will be a first (at least for me). Everyone is free to contribute to the list, but please be sure to cite or link to your sources.
I'll start:

I'll start:
- Before the Flood, the earth was surrounded by several kilometers of vaporized water floating in the atmosphere, thereby providing a source for the floodwaters (Whitcomb and Morris, The Genesis Flood).
- Before the Flood, there were fewer than 300 species of animals, which then underwent a period of extreme diversification following to the Flood, producing the hundreds of thousands of species we see today in just a few thousand years (AiG's Creation Museum).
- Before the Fall, T. rex used its massive, serrated teeth to eat plants (http://www.answersingenesis.org/articles/2007/08/31/feedback-t-rex-and-humans).
