How does Node.JS handle duplicate transitive dependencies?

I apologize if my questions are naïve. In full disclosure I'm relatively new to Node.JS and JavaScript in general. I'm hoping someone could shed some light on how Node.JS handles duplicate, possibly transitive, dependencies? Not even in terms of the global namespace or any kind of conflicts, or different versions of the same module (e.g. v0.1 vs v0.2 elsewhere in your app), but more around being smart and efficient where possible. For example:

• Is there any chance that Node is smart enough in terms of footprint to not have multiple copies of the same exact version of the library in your modules folder? Something like 1 copy for each required version with symbolic links or something similar pointing to this code for each module that depends on that version of that module?
• What about in terms of loading duplicate modules into memory at runtime? If v0.1 of module x is already loaded into memory, if some other depended upon module comes along that requires that same version of that module, will the code be re-loaded into memory, or is Node smart enough to see that code is already loaded and re-use it? How sandboxed is Node in this regard?

Thanks!