disassortative mating vs mating

disassortative mating and mating both are nouns.

Word	Noun	Adjective	Verb	Adverb
disassortative mating	Yes	No	No	No
mating	Yes	No	No	No

As nouns, mating is a hypernym of disassortative mating; that is, mating is a word with a broader meaning than disassortative mating:

disassortative mating: mating of individuals having traits more dissimilar than likely in random mating
mating: the act of pairing a male and female for reproductive purposes

Other hypernyms of disassortative mating include conjugation, coupling, pairing, sexual union, union.

disassortative mating (noun)	mating (noun)
mating of individuals having traits more dissimilar than likely in random mating	the act of pairing a male and female for reproductive purposes