>>11403719Beneficial. This has been proven by actual experiments that mixed previously isolated populations. It's even how several "invasive species" came to be. But it's confusing, because you may also see individuals that are worse of, at least initially.
AAAbb/AAAbb is the "purebred" first race. (capital leters signify advantageous genes)
aaaBB/aaaBB is the "purebred" second race.
Their first generation offspring is all AAAbb/aaaBB
The second generation (grand children) with two AAAbb/aaaBB parents get 50% chance PER GENE:
aaabb/aaabb (stupid)
aaabB
aaaBb
aaaBB
aaAbb
aaAbB
...
AAAbb
AAAbB
AAABb
AAABB/AAABB (genius not seen before the mixing)
All the combinations like AaAbB/aaABb can occur, too many to list them all.
But this is how it works. There may be bad combinations, but there will be combinations better than anything before.