There was approximately 15 other Homo type species ranging from Neanderthals to Homo-Erectus etc... we either wiped them out or they came much earlier than us. Homo-sapiens-sapiens (us), were the last to leave Africa and settle around the world. There were numerous others that did this in the hundreds of thousands of years before us, so we either got there and killed them off / outcompeted them or they did that to themselves.