They have a natural instinct to hibernate.
1	They	they	PRON	PRP	Case=Nom|Number=Plur|Person=3|PronType=Prs	2	nsubj	2:nsubj	_
2	have	have	VERB	VBP	Mood=Ind|Number=Plur|Person=3|Tense=Pres|VerbForm=Fin	0	root	0:root	_
3	a	a	DET	DT	Definite=Ind|PronType=Art	5	det	5:det	_
4	natural	natural	ADJ	JJ	Degree=Pos	5	amod	5:amod	_
5	instinct	instinct	NOUN	NN	Number=Sing	2	obj	2:obj	_
6	to	to	PART	TO	_	7	mark	7:mark	_
7	hibernate	hibernate	VERB	VB	VerbForm=Inf	5	acl	5:acl:to	SpaceAfter=No
8	.	.	PUNCT	.	_	2	punct	2:punct	_
