We are the proud owners of an 8 week old yellow lab, Gunner. He is much different than our last lab in that he seems to be a bit more vocal. Our new guy barks at his toy's, us & the occasional leaf or twig he can't reach.

Is there a way to determine if this early chatter will lead to a life of barking or if it is a sign of aggression?

I hardly think it is a sign of aggression. Puppies are puppies, they do strange things same as human babies. I am quite amused that he barks at twigs, etc. that he can't get. Dogs have their own personalities, as I am sure you know, same as us.

The spectrum has two ends & our last was on the opposite end as this guy. We believe/hope he is just testing to see what the limits are. We have rolled him on his back & normally he submits after a couple seconds. Like us he has his moments where it takes a few to relax. Thanks for your thoughts.

Puppies are certainly multi faceted they are just an unknown quantity for a certain period but more or less predictable I think. Yes, they have to test boundaries that's how they learn what they can't get away with.