palaeobotany vs palaeobiology

palaeobotany and palaeobiology both are nouns.

Word	Noun	Adjective	Verb	Adverb
palaeobotany	Yes	No	No	No
palaeobiology	Yes	No	No	No

As nouns, palaeobiology is a hypernym of palaeobotany; that is, palaeobiology is a word with a broader meaning than palaeobotany:

palaeobotany: the study of fossil plants
palaeobiology: a branch of paleontology that deals with the origin and growth and structure of fossil animals and plants as living organisms

Other hypernyms of palaeobotany include botany, phytology, paleobiology.

palaeobotany (noun)	palaeobiology (noun)
the study of fossil plants	a branch of paleontology that deals with the origin and growth and structure of fossil animals and plants as living organisms