How did Caucasoids(West Eurasians) orthognathism?

[Neolithic_Forager]

Prognathism is found practically in every race, most prominent in negroid race, but Caucasoids such as Europeans, MENA and South Asians have orthognathism.

So, what led to orthognathism in Caucasoids or west Eurasians?

Also, how did negroids end up developing prominent prognathism?

 

[Kurdquistador]

most south asians are not caucasoids but mixed race

and some "MENA" are also mixed race

 

[Ezio1]

most south asians are not caucasoids but mixed race

and some "MENA" are also mixed race

This.