I don't believe in reincarnation but had a phase of religious study. It's generally not a 1-to-1 mapping of you die and come back as a human. Depending on the religious school of thought "you" can spend some finite time in some afterlife (good or bad) then come back as some organism, not necessarily human. Also accounting for continued biological evolution may not be homo sapien if your "soul" comes back 1000 years later. Can't say I believe in reincarnation at all.