Many of these contemporaries had direct descendants, but not all of them left an unbroken link of descendants all the way down to today's population: in other words, some of these contemporaries are ancestors of no one in the current population.
Many of these contemporaries had direct descendants, but not all of them left an unbroken link of descendants all the way down to today's population. Some of these contemporaries are ancestors of no one in the current population. This is in other words.