1.

How does the biogeochemical cycle of carbon affect global climates?

2.

During an evolutionary radiation, organisms evolve rapidly. What would the geologic record look like if an evolutionary radiation occurred during an interval represented by an unconformity? How would you distinguish between an evolutionary radiation and the effects of the unconformity?

3.

Carbon and water are the basis for all life as we know it. If a giraffe made of silicon walked past one of the Mars Exploration Rovers, how would we know it was alive?