Although we are alike in so many ways, the small differences between individual humans are often times most relevant in shaping life experiences. A tiny chromosome determines whether we have the capacity to bear children or father them. A mere inch determines whether a child may or may not ride the newest roller coaster at Disneyland. We have little control over such differences. What we can control is how we react to or express our differences. The expression of what cannot be changed can be changed. We cannot change our genes, for example, but we can affect our epigenes, the expressions of our genes, by the choices we make every day. Choices, are what truly differentiate human beings from one another, and in fact, from other animals as well. The biggest differences between human and chimpanzee DNA actually lie within gene activation patterns.
The differences between chimps and humans are not in our proteins, but in how we use them.
Katherine Pollard (2006)
UC Davis Genome Center
The way our bodies use proteins may be based on our choices. Could it be that we are humans today because our ancestors made certain choices? Hmmm....
Will the choices we make today determine the micro-evolution of our species? Probably. Will the choices we make today determine the macro-evolution of humans? Hmmm...I'll have to get back to you on that.