Nowadays, that theory is rejected. Friedrich Wohler was able to synthesize urea from cyanic acid and ammonium, both being inorganic matter. <---This disproves the theory of vitalism.
I think the answer is "the older it is"
Reason: I might be wrong but is something (like a shell) gets buried in something (like sand), overtime many things (like dirt, soil, sand, etc.) will be on top of the original. This will make layers. So, the older rock is on the bottom since it has been there for the longest and it gets covered by other stuff (causing the layers).
Hope this helps! :) (If I'm wrong, sorry :( )
Top-down effects imply control through predation, including fishery, while
bottom-up effects imply control through food abundance, often thought to be driven by climate or nutrient load.
<h3>What is Top down regulation ?</h3>
The top-down effect refers to a higher trophic level influences the community structure of a lower trophic level through predation.
<h3>What is Bottom up regulation ?</h3>
The bottom-up effect means that a lower trophic level in the biological network affects the community structure of higher trophic levels by means of resource restriction
Learn more about Top down and bottom up regulation here:
brainly.com/question/18996262
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