When they were first sold, certain insecticides were highly effective in killing mosquitoes. today, dozens of mosquito generations later, a much smaller proportion of these insects die when sprayed with the same chemicals. fewer insects are killed today because

There are fewer mosquitoes dying because they have adapted to those diseases and chemicals and adapted immunities to them

Explanation:

one comes through sex and the other does not lul im not

an organism's phenotype is the  form of a trait  that it  displays. for  flowercolor, a pea  plant  can  display  a phenotype of purple or white flowers. an organism's  genotype  is the alleles of a gene it contains. based on his data, mendel concluded that a phenotype can be  determined  by more than one  genotype.