KTISIS in Mark 16:15 (C.S. Mann)

I understand that Mark 16:15 probably does not belong in the GNT, but we can still learn something from the Greek in that verse. Interested parties are encouraged to consult C.S. Mann, Mark (Anchor Bible Commentary). New York:
Doubleday, 1986. See pp. 672-75.

Mann translates Mk 16:15:

"And he said to them, 'Go into the whole world; make the Proclamation to the whole creation.'"

But what does Mann mean by "creation" in this passage?

On page 675, he provides this data:

"We have translated KTISIS as creation, which is the proper sense in 10:6 and 13:19, but it probably is here better understood as 'humanity' (cf. Col 1:23)."

It is my contention that Col. 1:23 could be understood in the same way: as a reference to humanity or to the human sphere.