If the dominant allele is t and the recessive allele ("non-taster") is n, than tn and tt are the genotypes of a "taster". tn is heterozygous and tt is dominant homozygous. nn is the genotype of a "non-taster" and it is recessive homozygous.
The deer population would drastically be reduced with the slower rate of reproduction and predators that would kill more deer than can reproduce. The environment would likely also have a reduced population of predators for deer, since the food source is reduced.
