First God said take the animals into the ark by twos, (Gen. 6:19), then he said by sevens of the clean animals (Gen.7:2), but when Noah actually did it he was back to by twos (Gen. 7:15)
I suppose at some point a scribe went, "Oh, wait, if Noah sacrifices one animal to Yahweh that's the end of the line for that species!" and he went in there to change it. Didn't do a global search-and-replace.
I suppose at some point a scribe went, "Oh, wait, if Noah sacrifices one animal to Yahweh that's the end of the line for that species!" and he went in there to change it. Didn't do a global search-and-replace.