linked to either industrial growth

[keannu]

What is the difference between ", linked" and "linked"? Was the comma inserted to describe "raw materials" a farther one as it can describe "Asian countries" without the comma?

ex)By comparing the composition of exports and imports in Africa's trade with Asia, one can easily observe complimentary relationships between Africa and Asia. African countries supply raw materials for Asian countries, linked to either industrial growth or emerging consumer populations in Asia....

[bhaisahab]

What is the difference between ", linked" and "linked"? Was the comma inserted to describe "raw materials" a farther one as it can describe "Asian countries" without the comma?

ex)By comparing the composition of exports and imports in Africa's trade with Asia, one can easily observe complimentary relationships between Africa and Asia. African countries supply raw materials for Asian countries, linked to either industrial growth or emerging consumer populations in Asia....

This doesn't read like it was written by a native speaker.

[keannu]

This doesn't read like it was written by a native speaker.

Okay, but I've seen other similar cases with or without comma, so could you please tell me what the difference is?