The Christian Faith in the Fall of Adam and Eve

Even if you take Genesis absolutely literally, there was already biological death in the world prior to the fall because Adam and Eve got to eat fruit. That is a consequence of the fall. And so you, and that wouldn't apply to their human ancestors because they weren't full theological modern biological humans. So yeah, their ancestors could have died leading up to the development of the biological form, which Pius XII said we can entertain and John Paul II endorsed. It's not incompatible with the Christian faith.