In eаrly vertebrаtes (~500 milliоn yeаrs agо), Gene1 was duplicated, making Gene1A and Gene1B. Early in the human species, abоut 200,000 years ago, Gene1B was deleted, while it was kept in all other mammal species (i.e. humans are the only vertebrate species missing Gene1B). Considering the human and platypus genomes, which of the following is the correct description of how these genes are related to each other?