A gene family is a group of related genes that share a common ancestor and typically have similar functions. These genes arise through processes like duplication and divergence, where a gene is copied, and the copies evolve over time to take on new roles. Gene families can be found across different species, highlighting evolutionary relationships. Members of a gene family often encode proteins that perform similar tasks in biological processes. For example, the hemoglobin gene family includes various genes responsible for oxygen transport in different organisms. Studying gene families helps scientists understand genetic diversity and evolutionary mechanisms.