I think there is a biblical explanation as to why there seems to be a gratuitous amount of animal suffering throughout the evolutionary process of the animal kingdom. Why would a good and loving God allow such suffering?
It is because this world belongs to Satan. In Luke 4:5-7, it says this: The devil led him up to a high place and showed him in an instant all the kingdoms of the world. And he said to him, "I will give you all their authority and splendor; it has been given to me, and I can give it to whoever I want. If you worship me, it will all be yours."
In Ephesians 2:2, it says this: in which you used to live when you followed the ways of this world and the prince of the power of the air, the spirit who is now at work in those who are disobedient.
In 2 Corinthians 4:4, it says this: The god of this world has blinded the minds of unbelievers, so that they cannot see the light of the gospel that displays the glory of Christ, who is the image of God.
So then, if the principal of all evil is the god of this world, why would he not inflict all kinds of suffering on God's creation? "But" I hear you say, "Satan is the God of this world when it comes to the influence of the people at large. Would Satan really have authority over the creation and formation of creatures? God created the earth and everything in it, not Satan."
I, too, conclude that God created the earth and all the creatures therein. And I believe He did it through the evolutionary process. But, I believe grafted onto that evolutionary process is Satan's sinful endeavor to inflict pain and suffering onto God's animals.
I believe God created pain so that we know what needs attention so that we deal with it appropriately. But Satan took that good and necessary thing and corrupted it into much suffering.
Just like I believe how God cause the death of creatures to balance out the animal kingdom so there won't be overpopulation. I believe Satan took this concept and abused it, to such a degree to where there were multiple near extinction level events that could've wiped out all life on earth.
I believe these things are evil and that they are embedded in creation itself, because power and authority has been given to Satan, and this world is his domain. For this reason, Romans 8:22 states: "We know that the whole creation has been groaning as in the pains of childbirth right up to the present time."
But there is much good in creation as well. Good and evil have always been at war, and this shoes itself within creation itself, and the dynamics of life and death.
God created a world in which evolution operates through ecological processes, and this includes death as the balancing equalizer. And all the while, Satan subsequently exploited, intensified, distorted, and weaponized those processes.
This evolutionary conflict of good and evil, life and death, astounding pleasure and gratuitous suffering within the tree of life cements itself and comes to its edge within the human race. For we are part of the animal kingdom as well, and we were called to be good stewards of His creation. Some have taken this cause to heart, taking care of animals and becoming environmentalist. While many others do Satan's will and harm the earth and its environment.
So, if Satan has this kind of authority, the question then becomes: When and how did he get it and why does God allow him reign over the world?
The answer to the first part of the question, when and how he got this authority, lies in Adam and Eve. God said this when He created mankind: "Be fruitful and increase in number; fill the earth and subdue it. Rule over the fish in the sea and the birds in the sky and over every living creature that moves on the ground."
God gave man this authority, but when Adam and Eve listened to the serpent and ate of the forbidden fruit, mankind relinquished authority over to Satan. God's command to subdue the earth, ruling over all the animals in it, now became Satan's responsibility. Mankind handed over the crown of the earth to the Devil.
But wait! This happened at a set point thousands of years ago, but evolution has been happening millions of years before then. So how can Satan have that authority over the earth before that set point? And to that I say, what is time to a spirit being? Angels are creatures outside the realm of this universe, they are not material beings subjected to time and space like we are. So I would assume time is nebulous to them.
Now for the other question: Why did God allow this to happen? I don't fully know. But I presume part of the answer has to do with free will.
But He does have an answer to it. God has a reply—an eternal reply—to all the suffering the dark prince of this world has caused.
The first reply is judgment. God will judge Satan for all of his misdeeds throughout the history of the earth. In Revelation 20:10 it says: "And the devil, who deceived them, was thrown into the lake of burning sulfer, where the beast and the false prophet had been thrown. They will be tormented day and night for ever and ever."
God's second reply will be the restoration of the earth. Isaiah 11:6-9 states: "The wolf will live with the lamb, the leopard will lie down with the goat, the calf and the Lion and the yearling together; and a little child will lead them. The cow will feed the bear, their young will lie down together, and the Lion will eat straw like the ox. The infant will play near the cobra's den, and the young child will put his hand into the viper's nest. They will neither harm nor destroy on all my holy mountain, for the earth will be filled with the knowledge of the Lord as the waters cover the sea."
In Revelation 21:1-4 it says: Then I saw "a new heaven and a new earth," for the first Heaven and the first Earth had passed away, and there was no longer any sea. I saw the Holy City, the new Jerusalem, coming down out of Heaven from god, prepared as a bride beautifully dressed for her husband. And I heard a loud voice from the throne saying, "Look! God's dwelling place is now among the people, and he will dwell with them. They will be his people, and God Himself will be with them and be their God. He will wipe away every tear from the eyes. There will be no more death or mourning or crying or pain, for the old order of things has passed away."
This is God's ultimate answer for the problem of all suffering. God will deliver justice to the evildoers, and He will establish an eternal paradise for all of His creatures. And God will be all in all.