natural scientist vs biologist

natural scientist and biologist both are nouns.

Word	Noun	Adjective	Verb	Adverb
natural scientist	Yes	No	No	No
biologist	Yes	No	No	No

As nouns, biologist is a hypernym of natural scientist; that is, biologist is a word with a broader meaning than natural scientist:

natural scientist: a biologist knowledgeable about natural history (especially botany and zoology)
biologist: (biology) a scientist who studies living organisms

Other hypernyms of natural scientist include life scientist.

natural scientist (noun)	biologist (noun)
a biologist knowledgeable about natural history (especially botany and zoology)	(biology) a scientist who studies living organisms