well, actually, only the cows and goats and other herbivores got to live forever in the garden of Eden. other animals who were carnivorous and who were forced to eat grass, all died fairly quickly as their digestive systems could not handle the biomass. amazingly, this would have made them the bottom of the food chain, as they decompose and turn into earth, other cows and goats eventually ate what they once were. ;)
seriously though, when you think about it, death is a real part of evolution, even for humans, ironically. as long as the animal lives long enough to pass on it's genome is all that matters. if there was no death, there would be no evolution, and no biodiversity. life would not survive the great extinctions.
but of course genesis is absolutely absurd on all points it makes. i can't think of a SINGLE one that is true. it makes a very cute case for anthropocentrism. but then again, that's all anthropocentrism has ever been: cute. genesis is the grand daddy of cutesy cozy anthropocentrism.
surely, god/ jah / jesus / allah in his great omnipotence and omniscience created the animals perfectly, but then had to cripple their genomes so that they would die, and the "special" homo sapiens would be the only ones to live "forever". but then when they sinned, god too crippled their genome, so that they could only live a limited amount of time, along with their close genetic relatives the pan troglodytes, chimps. he then started letting all the canine toothed carnivores eat other animals.
this is, of course, unfalsifiable, because it conveniently happened way back in the past, and there is no current evidence to support it. actually, it all points away from genesis, the great book of human specialness.
what a load of BS.
ts