When a Sentient being has passed away, she/he has no sensation or thoughts in the manner we knew it; the spirit however is in continuum ( in another Realm) and so are the consequent sensations of mind, being eternal.

Sentience differs from the non-sentience ; Sentient beings have breath spirit , eternally, energy being indestructible.

Upon receiving Spirit Pneuma breath, a being instantly has sensations : genetic , with 1st beings having had that of the Parent creator Being.

Nurture, Influence

Non Conscious has no spirit , and thus no emotions or thoughts .

No sentient species evolves into another species nor into non sentience , it is observed and obvious.
Very intelligent animals, some are more brilliant ( measured eq, iq) than some humans, stay as animals :ex..

Laws of Thought do not allow Species to change into another species, naturally and functionally

Development of thoughts and emotions occur , based upon intent , within same being & species: evolution of Sentience from nonSentience cannot occur , since the latter has no breath consciousness nor ability to impart it

Feelings are Superior cognitive based and with true beings, feelings are as Conscience spirit