Where does “ἐπιζευγνύναι” come from?

ἐπιζευγνύναι (Ancient Greek) comes from Ancient Greek ἐπί, from Ancient Greek Ἡμέρα, from Ancient Greek ἦμαρ, from Proto-Hellenic ā́mər, from Proto-Indo-European h₂eh₃mr̥, from Proto-Indo-European h₂eh₃- — to be hot; to burn.

Ancestry of “ἐπιζευγνύναι”, step by step

ἐπιζευγνύναι traces back through two separate lines of ancestry.

via Ancient Greek ἐπί

Step	Language	Word	Meaning
1	Ancient Greek	ἐπί	as well, besides; For usage in composition, see...
2	Ancient Greek	Ἡμέρα	—
3	Ancient Greek	ἦμαρ	day; by day; midday
4	Proto-Hellenic	ā́mər	day
5	Proto-Indo-European	h₂eh₃mr̥	heat
6	Proto-Indo-European	h₂eh₃-	to be hot; to burn

via Ancient Greek ζεύγνυμι

Step	Language	Word	Meaning
1	Ancient Greek	ζεύγνυμι	To yoke, saddle, bridle a beast of burden...
2	Ancient Greek	ζεῦγος	pair, two things, persons or animals considered...
3	Proto-Indo-European	yugóm	yoke
4	Proto-Indo-European	yewg-	to join, to yoke, to tie together

Every word from Proto-Indo-European h₂eh₃- →Every word from Proto-Indo-European h₂eh₃mr̥ →Every word from Proto-Hellenic ā́mər →