3. (two points) A population of humans, isolated for centuries
on an island in the Indian Ocean, exhibits the following phenotypes
for the M N blood group locus. 330 M 375 MN 295 N LM and LN are two
codominant alleles at this locus. LMLM alleles give type M blood.
LMLN individuals are heterozygous. LNLN individuals are type N
blood.
a) What might be going on here? What factors might cause a
distribution of genotypes like this?