This sacrifice allows selfishness to exist at all, not the other way
around. Selfishness is a luxary afforded by selfless sacrifice. Even
perhaps a prey giving up his/her life to the predator may be seen in
some ways as a successful sacrifice allowing life to continue. It may
be an extremely difficult thing to do to give up one's life for
another and even Jesus wanted to avoid it if at all possible, but from
Jesus death sprung new life of modern culture.
The study of the selfish gene is the study of the destruction of life,
not it's creation. Biology in the form of the modern Darwinist
perspective is the study of death, not life! I may not be able to
parse out my arguments super clearly because I do not understand. For
instance, what benefit does it bring to the animal that sacrifices.
The answer may be eternal life for the organism, but this does not
seem to exist in the Scriptures. Only humans seem to get eternal
life.
Service to the creator may be reward enough and the attainment of some
kind of Nirvana for the organism that sacrifices and "hears", "Job
well done."
Science has been now been too narrow minded. The selfish gene may
like Newtonian Physics explains gravity, explain most of life, but it
doesn't explain it all, and it is not fundemental nor is it
foundational!!!