I suspect the meaning was that romance in a form that we would recognise as being romance appeared then? However, it is worth noting that not every culture has romantic pairings in the same way as we do. If I remember correctly, in Papau New Guinea (or possibly the Trobriands, it's been a while) children are looked after by the mother and her brother, so the relationship between lovers is obviously very different. Therefore, to say that romantic love is something inherently human is not necessarily logically true.

You may have better luck in /r/AskAnthropology, as this is a rather broad question for this subreddit.