Without putting one's own spin on anything. The Word of God gives us hints once in a while . Most people who read their bibles, do not look for something new and interesting. They look for old reliable things that they have come to know and understand. New understandings ( call them revealings if you like ) are only new to the hearer. Not new to the scriptures, as they have always been there.
The word - "replenish" has always been in Gen. 1:28 , but overlooked, or just plain ignored, because of one's present belief.
A simple understanding of this word - "replenish", is to replace something that was previously there. The item does not have to be exactly the same, but similar. Like a lawn mower. Today, our lawn mowers are engine powered and most are riders. But 90 years ago, most were push lawn mowers. The power came from the person pushing it. Today, we ride, and the engine provides the power.
If someone has been selling lawn mowers for nearly 100 years. They "replenish" their line of lawn mowers with the newer brand. Looking back nearly 100 years, one would have to be in better physical shape to mow one's lawn. Today, you can be fat, overweight, lazy, and do not have to lift anything that is over a one pound cheese burger, in order to mow your lawn.
This earth is very old, but how old, only God knows.
But the hints from within the Word of God tells us that life was here on this planet prior to Adam , and the animals and plant life that God created and made from Gen. 1:7 up until Gen. 2:25.
For the things that God made, are the things that God did not have to create. Anything that God created, didn't exist in its present form or shape of life prior to God creating it. This is the difference between God making , or setting something, and God creating something.
When God created the Heaven and the Earth. Neither a heaven nor an Earth ever existed before. This is why God created both. And this is why God did not "make" the heaven or the earth.
When God created the Heaven, it was not a vast empty piece of space with nothing there whatsoever. God put life within Heaven. Himself and the angels. The same holds true with when God created the earth.
But for the most part, people either refuse to accept certain hints of truth, because it means that one would have to renew one's mind to this truth. Or they are blinded by their ignorance to remain ignorant.
Even the Apostle Paul told the Church, that if someone wants to remain ignorant, let them remain ignorant. This means that nothing should be force fed. Acceptance is the desire to search out and find the truths, even if they are only these little hints from within the Word of God. God is a God of life. (hint)
Where God is, there is life. Where God creates, his creation has life.