[Aztlan] Questions about vegetation on Mesoamerican ruins

[Jules Siegel]

Over the years I have tried to find answers to the following questions 
without much success. I tried Internet searching again today and found 
myself dealing with a bewildering variety of irrelevant hits no matter 
how I formed the search pattern. I'd very much appreciate some thoughts 
about these points based on sound scientific research rather than 
speculation. Many thanks for your consideration, folks.

What is the tallest structure entirely covered in vegetation growing on 
it (as opposed to around it forming a canopy)?

How did the vegetation get there?

What kind of vegetation is typically found?

How deep are the roots?

The depth of the soil?

Is it true that seashells have been found in the soil on top of 
Mesoamerican monuments? If so, how did they get there? What kind? Age?

-- 
JULES SIEGEL Apdo. 1764, 77501-Cancun, Q. Roo, Mexico
http://www.cafecancun.com/bookarts

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