It would take 100 person-years for a genealogist to map and find all the parents for five million people – with a rate of one person per minute. The AncestryAI algorithm can do the same work in an hour using 50 parallel computers and with a success rate of 65 per cent. The algorithm can also measure the level of uncertainty for each connection so that unreliable results can be ignored. Genealogists and demographers can use the algorithm to shed light on societal change and history.