[firebat45]

I'd argue that 2 entities taking turns vocalizing (or similar) with each other with the intent of the other responding back is the base definition of a conversation.

No, they didn't discuss the finer points of Hume's philosophy. It was just the "first" conversation, after all.

[more_corn]

Did they communicate any ideas or did they just make sounds at each other? I can talk to my cat all day, and even if he responds you can’t really call it a conversation. A conversation would require that we know what the sounds mean to the other. It’s unclear from the article if that is happening.

[shermantanktop]

You may be telling your cat “what a good girl you are,” but she hears 1) you want her attention 2) you are paying attention to her 3) you are being positive and friendly (by tone of voice).

Are those ideas? No, but I’d argue they are equally and sometimes more important than ideas.

That type of meta-communication is most of the substance of many human conversations as well, even if the two people are talking about the finer details of weather or whatever.