What did Charles Lyell's Principles of Geology impress upon Darwin?
the age of the earth may be much older than once thought
that populations are naturally limited
o that finches are the best potential model organisms for evolution
Lyell described Natural Selection

Charles Lyell's principle that the age of earth may be much older than once thought impressed upon Darwin.

Explanation:

Charles Lyell is one among the earlier thinkers whose studies influenced Darwin and he lived in the 1797-1875 period. while on his voyage in Beagle Darwin took the book of Charles Lyell, Principles of Geology with him.

In this book Lyell argues that the earth's surface was formed as a result of gradual geological processes indicating that the earth was much older than what many believed at that time.