1. When birds migrate into or out of a defined population and mate with birds from another population, the existing pool of genes may be altered. Migration can increase or decrease gene frequencies in
populations, resulting in...

i think it is dna, i'm not totally sure but i think it might be.

this is true, assuming that the allele is completely recessive and incomplete dominance is not a factor.

fossil's are like over rated rocks like low key not gonna lie i don't get why we can't just call them old rocks like for real i mean i call my grandpa and grandma that smh