The Boundary Disappeared but Stayed Inside

Scientists compared nearly six thousand animal genomes and found traces of the same ancient groups of genes.

When two chromosomes fuse, their contents slowly mix. Millions of years later, the boundary between them may be gone. Simply splitting them again will not bring back the original state.

It is like mixing two paints. The boundary disappears, but the mixture remains.

The past does not decide exactly what a system will become. It changes what can happen next. A genome keeps evolving, but it never gets to start over.

Maybe something similar happens to people and cultures. The past does not completely determine us. But some events change what we are still able to become.

How free are we to choose our future if the choices themselves have already been shaped by events that cannot be undone?