How does modern day christian theology explain and ...

I din't know that they might say but the old explanation was based on Genisus 1 : 28.

It was known as the "gap theory" . That is the world became , changed, and was repopulated. That does seem consistent with records

I don't know about modern day theology but I see no conflict in what Genesis describes and what paleontology reveals. Creatures DID come forth from the waters unto the land masses and evolve.

And now-------

Straight from the missing books of the Bible, the answer that you have been waiting to hear!

God was running a daycare and got an extra truckload of Play Dough. Since He had sent UPS to hell, this was the first time, He gave it to the kids and the kids made lots of big bones. GOD had a thot. He buried the bones in various strata of His newly created earth and to this day He still chuckles about the big joke on all the archeologists.

Sigh. If I could only insert a Share Button with this answer.

Neither animals nor man are made of clay. They are made of chemical molecules that came together IN clay from the earth.

As it was written.   

In the beginning there was a dumb story. And some idiots read the dumb story and twist it in their minds in order to believe it agrees with science.

Intelligent rebuttal there. Not.   

They don't explain nothing or they lie.  Do you believe anyone who puts their entire faith into a thing without any justification but tons of reasons not to?  Most religions are stupid, but Christianity is particularly evil.