The reason I ask is science has found numerous extinction events throughout history including 5 major ones. If God created every animal and species at a particular day/age, how does that reconcile so many animals that had gone extinct before man even arrived. Why create them in the first place?
Like I always say, I keep science and the bible separate.
Since your question assumes that God is the Creator, then the basis of the answer should not be science but the bible.
If you don't believe in the bible, then that's OK, but we won't have anything to talk about.
If you believe in the bible, then well and good, since we will have a point of common agreement.
=================================
The bible does not explain why God allows certain species to become extinct. If the bible does not supply the information, then we should just admit that we don't know the answer, because part of the discipline in studying the bible is to be careful not to add things that are not written.
All the bible says is that God has sovereignty over all creation, so He is free to do what He wishes; therefore we, being His created, have no right to question His will. All we know from the bible is that extinction, if brought about by nature and not by man's actions, is just part of the way nature works, as God designed it.
We don't have to go into the topic of extinction, actually. Why don't we just ask, "Why did God create animals at all?" If the Creator is powerful enough to create the universe, then surely He would also be powerful enough to create a human that doesn't need food to survive, or to create an earth that doesn't need animals to maintain balance.
But that's how God designed nature, and we have no right to question His design. If a potter wants to make a pot in a certain way, will the pieces of pottery have any right to question the potter's decision?
This concept is explained by Isaiah as follows:
9 “Woe to those who quarrel with their Maker, those who are nothing but potsherds among the potsherds on the ground. Does the clay say to the potter, ‘What are you making?’ Does your work say, ‘The potter has no hands’? (Is. 45:9)
Shall what is formed say to the one who formed it, “You did not make me”? Can the pot say to the potter, “You know nothing”? (Is. 29:16)And Paul explains it this way:
20 Nay but, O man, who art thou that repliest against God? Shall the thing formed say to him that formed it, Why hast thou made me thus? 21 Hath not the potter power over the clay, of the same lump to make one vessel unto honour, and another unto dishonour? (Rom. 9:20-21)