It seems that zombies have some intelligence in this series instead of being mere mindless walkers.

- They are able to sit / lie down instead of always walking around. They require "rest?"

- As seen on "Seed," they seem to be aware there's a fence, as they prefer to go for the group within the yard rather than be lured by the secondary group behind the fence. This means they can calculate priorities.

- As seen on "Seed" again, they are able to play dead (the one who bit Hershel). Is this a hunting strategy?

- They are able to walk over obstacles (rocks, stairs, dead bodies). Generically, I assumed they would trip over these. They utilize efficency?

Any thoughts?