The concept of gene flow is demonstrated when a cow is driven off from its herd, joins another herd, and reproduces. When the cow contributes to the gene pool of the new herd, which of these most likely increases?

Complete question:

The concept of gene flow is demonstrated when a cow is driven off from its herd, joins another herd, and reproduces.  When the cow contributes to the gene pool of the new herd, which of these most likely increases?

genetic variation

Explanation:

Whenever migration occurs between two populations, there is genetic flow going on. Genetic flow is an evolutive strength only if migration > 0 and if the allelic frequency in one generation is different from the allelic frequency in the next generation.

Genetic flow acts homogenizing the allelic frequencies between the two populations, and it might introduce variability into the new one.

For genetic flow to be possible, there needs not only the movement of the genes from one population to the other but also the reproduction process on the new population. Hence, it involves an interaction between the dispersion pattern and the reproductive system.

The bigger the difference in allelic frequencies between populations is, the bigger is the effect of the genetic flow.