The reader is informed that it is the spirit (ruah) in man that provides understanding of God…
But it is a spirit in man giving them understanding, even the breath of the Almighty.(Job 32.8)
Contrasted to this, are animals which have no understanding of God (i.e. no spirit)…
Be not like the horse, like the mule, with no understanding; with bit and bridle his gear to be held in, that they do not come near you.(Psalm 32.9)
Psalm 49 brings these two concepts together...
It states that both animals and humanity perish (Psalm 49.10, 12, 14, 20) - but ONLY humanity, with understanding of God, can be redeemed (Psalm 49.15).
Since animals have no understanding of God, then they cannot possibly have redemption, and they are forever in the grave as their final resting place.
Simple Biblical Truth...