<< Why is a naturalistic explanation
for this transition "unreasonable"? Modern cultures have arisen in far
less time.>>
Because you have once again mixed apples and oranges. As I've explained
before, the appearance of "culture" is one thing. The actual appearance of man
is another ("culture" is what this new man created).
That is what both Eisley and Goodman are addressing. You are focusing on the
wrong topic. "Today, Darwin's theory of evolution does not adequately explain
what we know of the phenomenon of man." (Goodman). That's what has yet to be
explained.
If you want your view to seem "reasonable," then you'll have to provide some
basis for it.
Jim