It was an evolution.
1	It	it	PRON	PRP	Case=Nom|Gender=Neut|Number=Sing|Person=3|PronType=Prs	4	nsubj	4:nsubj	_
2	was	be	AUX	VBD	Mood=Ind|Number=Sing|Person=3|Tense=Past|VerbForm=Fin	4	cop	4:cop	_
3	an	a	DET	DT	Definite=Ind|PronType=Art	4	det	4:det	_
4	evolution	evolution	NOUN	NN	Number=Sing	0	root	0:root	SpaceAfter=No
5	.	.	PUNCT	.	_	4	punct	4:punct	_
