biology vs ecology

biology and ecology both are nouns.

Word	Noun	Adjective	Verb	Adverb
biology	Yes	No	No	No
ecology	Yes	No	No	No

As nouns, ecology is a hyponym of biology; that is, ecology is a word with a more specific, narrower meaning than biology:

biology: the science that studies living organisms
ecology: the branch of biology concerned with the relations between organisms and their environment

biology (noun)	ecology (noun)
the science that studies living organisms	the branch of biology concerned with the relations between organisms and their environment
all the plant and animal life of a particular region	the environment as it relates to living organisms
characteristic life processes and phenomena of living organisms