Clearly, God was planning ahead; He knew that Adam and Eve would sin and thus invent death; they would have to be able to procreate and Eve would need nipples; since Eve was made out of Adam, he needed nipple genes.
But the "planning ahead" theory doesn't account for why God had to try Adam with every other creature of his creation before figuring out that Adam preferred humans. God isn't portrayed as a very good planner in that story.
It would also seem odd that God would have to give Adam characteristics he planned to copy into Eve since he was pretty much starting over when he made her and did a perfectly fine job endowing her with traits not found in Adam.
In the other creation account God makes them both at the same time and could have just done it proper from the get-go.
I don't think we can trace nipples back to Adam as preperation for Eve.
On the other hand, there is the good hand-waved answer: Adam did not have nipples himself but both sexes acquired them after they were added to Eve, for whom they had good use. This doesn't explain why God did not make only women have nipples as he could easily have done, but perhaps leaving out that perameter was just an oversight (more hand-waving).
Jon
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