marine animal vs brute

marine animal and brute both are nouns.

Word	Noun	Adjective	Verb	Adverb
marine animal	Yes	No	No	No
brute	Yes	Yes	No	No

As nouns, brute is a hypernym of marine animal; that is, brute is a word with a broader meaning than marine animal:

marine animal: any of numerous animals inhabiting the sea including e.g. fishes and molluscs and many mammals
brute: a living organism characterized by voluntary movement

Other hypernyms of marine animal include animal, animate being, beast, creature, fauna.

marine animal (noun)	brute (noun)
any of numerous animals inhabiting the sea including e.g. fishes and molluscs and many mammals	a living organism characterized by voluntary movement
	a cruelly rapacious person

marine animal (adjective)	brute (adjective)
	resembling a beast; showing lack of human sensibility