In this study, we have based most calculations on an individual,
adult Weddell seal of 450 kg, and as such, the data only apply directly
to this seal. However, the qualitative conclusions and all the semiquantitative
trends of the mutational impacts on ADL remain valid
for other diving mammals, although the input parameters and exact
values will of course change. Impairing KO2 in Mb will affect ADL in
all these mammals, but how much depends on the physiological and
compensatory mechanisms of each organism. We have shown here
that the observed effects of single-mutations in Mb reducing ADL,
with either deleterious or marginal effects on fitness, will be qualitatively
and semi-quantitatively similar for other individuals and for
sea lions. Thus, the prevalence of H64 and the natural variation in
some sites that do not substantially change ADL can be explained
from the present model.