Far be it from me to bring Christianity into any argument.  But I have no problem with predicating them on biology--kinda what I do.  Have you ever seen big Brownie rip open the belly of a gasping mama salmon to get at the roe?  Ever seen an octopus crush and dismember a crab one leg at a time?  How about watching a golden eagle rip apart a still-living rabbit?  Or a tarantula injecting a substance into its insect prey that essentially liquifies its internal organs as it frantically struggles to escape?  Or a Nile crocodile seize a wildebeest by its nose, drag it into the water, then roll to twist big chunks of meat and bone from the still-living animal?  Should we make all these "cruel" creatures illegal, Evan?  Force them to eat only plants?  Good luck.