Wish they had explained the Warrior Maidens and Mandora better.

Safari Joe was human.
I've had my 15 minutes,now what!

Yes, there were some humans living on Third Earth, including the Warrior Maidens, Dr. Dometone, and the Berserkers. There were also humans who came to Third Earth from outer space (e.g. Mandora, Safari Joe) or originated on Earth in the past (e.g. Hachiman, Wizz-Ra). I don't think it was ever explicitly stated on the show, but it was implied that Third Earth was our Earth some time in the distant future.
^This! Plus a few other character who were human looking also turned up in the series like; Malcar, Queen Tartara and The Shadowmaster!
The classic series wasn't purely all 'Anthromorphic humanoid animals' and had a smaller percentage of actual humans in there as well!
ST4
Finally VF5:FS
http://www.youtube.com/watch?v=p_qjJ6eI1Og&feature=player_embedded

I'm not quite sure Wiz-Ra counts as human, although he certainly looks like one. Until the creation of Mumm-Rana, he was implied to be Mumm-Ra's past opposite.
I think you're right about Third Earth being in our distant future. My guess is we really did wipe oursleves out with a nuclear war in this version of events.

Yes, there were some humans living on Third Earth, including the Warrior Maidens, Dr. Dometone, and the Berserkers. There were also humans who came to Third Earth from outer space (e.g. Mandora, Safari Joe) or originated on Earth in the past (e.g. Hachiman, Wizz-Ra). I don't think it was ever explicitly stated on the show, but it was implied that Third Earth was our Earth some time in the distant future.