Then it all comes down to belief then, doesn't it?
Death is an established fact. How it came into the world is debatable. I believe intelligence is eternal and that all people and animals have intelligence. It's interesting to note that when Adam fell, God brought the couple garments of animal skins. Scholars have debated where these skins came from and how they came to be, but we have to accept that there are some things we'll never know for sure. And some things will always be a matter of faith.
The topic is why God allows suffering. Christians say the answer is, 1) God will not act in a way that will interfere with man's free agency, and 2) all suffering is temporal and therefore the worst people can inflict is death, which does not end one's existence, but frees the spirit to return unto God. Only in the atheistic universe is death the end of the line. “As in Adam, all die, even so in Christ shall all be made alive." Regardless of when predation began, every living thing on Earth, every bug, every plant and even Earth itself will eventually be made whole and glorified because of Christ.