Can you give me some positive effects of human migration?

Question

I have these:

-Economic development

-Provide labor

-Cultural exchange

I need two more.

Answer 1

Could avoid some negative condition at the original location (over crowding, famine ,etc.)

Could allow use of new resources at the new location.

Answer 2

"America" is a great example of positive human migration.  No migration, no Americia!

Answer 3

Provide critical skills, skills in demand like nurses for north america coming from india, phillipines

Training and education. Folks from asia coming to the best US schools and getting trained. A lot of them go back to run enterprises back home, All this creates development and opportunities.