Do not fear, God cannot die, niether can the evil one. Earth, is the only plane of existance where light and dark can co-exist. We can be at different stages of spiritual eveloution. It will always seem that the lesser spiritually developed humans will be more influential, but thier in their own process of eveloution, and the more developed are developing their spririts and humility. Upon Jesus's Death, Thomas went to India where he influenced the beliefs of the Hindu's aand Buddist.
Animals are at the beginning of the road.
First, we came from the creatures of the see, to the land, to the air, then humans. The more we distroy nature, the greater the world human population grows, the more lesser developed animal spirits will be reincarnated as humans. But this is all our doing.