There had to be a reason... A herd of buffalo can only move as fast as the slowest buffalo and when the herd is hunted,

There had to be a reason...
A herd of buffalo can only move as fast as the slowest buffalo and when the
herd is hunted, it is the slowest and weakest ones at the back that are
killed first. This natural selection is good for the herd as a whole,
because the general speed and health of the whole group keeps improving by
the regular attrition of the weakest members. In much the same way, the
human brain can only operate as fast as the slowest brain cells. Excessive
intake of alcohol, we all know, kills brain cells, but naturally it attacks
the slowest and weakest brain cells first. In this way, regular consumption
of beer eliminates the weaker brain cells, making the brain a faster and
more efficient machine.
This is why you always feel smarter after a few beers!