no meat for predators

Recently, i had a discussion with a fellow Christian who believes, with all of his heart that there were no animals killed by other animals until after the flood of Noah.
Someone comment, please, if there is a scripture that supports this. Why is this being taught? Does it somehow create a different picture of God?

I know that no human can understand Gods nature. We need revelation from the Word of God. Somehow, the God i know isn't like this.

Ok, angels, check this out. I am going to create a creature. This creature shall be called a lion. It will have dense muscular tissue enabling great speed and strength. Its jaw will bite down with sufficient force to crush any creatures skull. It will have claws that can disembowel a victim with one strike. It will be very skilled in subterfuge, stalking, and approaching other animals. It's roar will paralyse any lesser creature by fear alone. And he will live on salad.

My friend argued that the claws were to tear bark from trees. So what were the teeth for? Lion teeth, like almost all predatory creatures are not only sharp, but angled back to create a barbed effect so that the animal held therein cannot escape. Plant eating animals have flat teeth to mash up plant material. Humans, by the way, have both.

So, which creature do you think God created?