Thanks Tracy for pointing me to:
Passage Ecclesiastes 3:19-21:
19For that which befalleth the sons of men befalleth beasts; even one thing befalleth them: as the one dieth, so dieth the other; yea, they have all one breath; so that a man hath no preeminence above a beast: for all is vanity.
20All go unto one place; all are of the dust, and all turn to dust again.
21Who knoweth the spirit of man that goeth upward, and the spirit of the beast that goeth downward to the earth?
But I still don't get it 100% lol! I always need everything explained.