systematist vs systematics

systematist and systematics both are nouns.

Word	Noun	Adjective	Verb	Adverb
systematist	Yes	No	No	No
systematics	Yes	No	No	No

systematist (noun)	systematics (noun)
a biologist who specializes in the classification of organisms into groups on the basis of their structure and origin and behavior	the science of systematic classification
an organizer who puts things in order