You can still easily trace the ‘creation in seven days’ in the bible today. Just focus on the interrupting sentences: "and God saw that it was good"!

Overall, Genesis 1 follows a strict pattern:
(a) God creates something
(b) There´s a closing sentence, “And God saw that it was good. And there was evening, and there was morning—the [number] day.”

But on Day 6, there’s a curious and sudden exception. God creates the animals (1:24-25), sees that it is good – and then doesn’t call it a day, but unexpectedly goes on to create Adam and Eve, as a kind of extra.

This strongly suggests that what is now Day 6 originally consisted of two separate creation days. God would have created the animals on Day 6 and Adam and Eve on Day #7 – which of course makes more sense (see table).

Also, the ‘creation in seven days’ would make sense for another reason. It is a well-established fact that the biblical creation story is partly based on another, much older creation myth: that of the ancient Persians, the ‘zoroastrians’. And in zoroastrianism, it takes God seven days to create the world.

There is another creation day which doesn’t follow the strict creation pattern: Day #2. The mantra "and God saw that it was good" only comes later, during Day 3.

This too suggests that the original creation myth was slightly different. God would have separated heaven and earth and land and sea on one day, which indeed fits the ‘creation logic’ much better. Basically, it would read that on Day 3, God put the water so that there was land and sky.