In addition to the appearance of the antifreeze gene, icefish have also been found to have DNA sequences similar to the
DNA sequences in hemoglobin genes of other fish species,
However, these DNA sequences are not complete and therefore
not functional in icelish. This evidence makes it likely that
KO
A. icelish ancestors
had hemoglobin
B. icefish will soon
produce offspring
with hemoglobin
C. hemoglobin is a
molecule made by
some fish that do
not have genes for it
D. Soon all fish will
stop producing
hemoglobin

In birds and mammals, genes that code for α-globin are located on a different ... Redundant gene sequences have been selected against and removed over time. ... All of the species beyond point B share the same missing portions of DNA. ... No functional hemoglobin → presence of antifreeze proteins → loss of functional

•there must be variation for the particular trait within a population.

•the variation must be inheritable (that is, it must be capable of being passed on from the parents to their offspring).

•individuals with one version of the trait must produce more offspring than those with a different version of the trait.good

explanation: