Ask A Scientist© Biology Archive

If the theory of evolution is true how did we evolve morel (right and wrong)?
Andrew M Harvey

Answer 1:  Evolution requires two things: first, mutation.  That is, each
generation must have some chance to be unlike the previous.  Second,
natural selection.  That is, the individuals in each generation who are
better suited to their environment must be more likely to produce children.
If these two things are present, then a species will evolve to become
better suited to its environment (you can easily prove this). Notice that
"better suited to its environment" does not necessarily mean "nicer," "more
intelligent," or "stronger;" it all depends on what works best in the
environment.  Now if we assume that the moral nature of human beings is
different now than it was in the past, then evolution could have caused
this difference if the two parts of evolution (mutation + natural
selection) are present, that is if each generation of humans is a little
different morally from the previous, and if more (or less) moral humans are
more likely to produce children.
Christopher Grayce

Answer 2:  The theory of evolution explains how humans (and other organisms) 
came to have the biology that we do---walking upright, big brains, etc. The
Theory of evolution does not necessarily explain why human beings today
behave the way we do. For example, all humans are one species, but we
speak many different languages. That we can have language at all is
due to our biology (our brain and vocal cords), and thus due to
evolution. The differences in the languages we do speak (Spanish, English,
Russian, etc) are due to something else---differences in culture.
 
So I would say that morality is not really a "biological" trait. Just
like with languages, what is moral in one culture is not moral in another.
Also, what was moral 400 years ago is no longer moral today. Evolution
only happens over much longer periods of time (tens of thousands to
millions of years), so it can't be responsible for morality. Morality
is just something that we humans have invented on our own, just like
we invented Spanish, English, and Russian.
 
David DeGusta