That is what I was told by a botany professor.

mel turner schreef
Okay, but even botany professors may make mistakes. I suspect that
this was just an error.

+ + +
I am uneasy. I will admit to having heard botany professors making erroneous
statements, when talking outside their own field. However I have also heard
botany professors making statements that seemed unbelievable, but did check
out.
+ + +

Where inside the plant are the blue-greens supposed to live?

In the leaves.

+ + +
Are you sure that he meant inside the leaves, or could he have meant in some
exterior feature of the leaves?
+ + +

There are more things in heaven and earth, Horatio, than are met with on
the Web.

Of course.

[...]
Probably at some time during the Ice Age, F.carica hit on this solution
to the problem of a shorter growing season and less light than its fellow
species.

+ + +
No matter what is the case here, the Ice Ages will have nothing to do with
it? Wrong area and wrong timescale.
PvR