What evidence supports the theory that human life began on the continent of Africa?

a new genetic study suggest all modern human trace our ancestory to a single spot in Africa

one of the main reasons was definitely slavery. back in 1861, republican abraham lincoln was elected and ended up being a major influence in the slavery business. slavery greatly affected the texas economy because back in 1845 during the annexation of texas, slaves became a big part of the texas population. many texans that were in favor of the secession influenced groups through party ties.