Picture yourself on the stage of a large theatre with room for an audience of two thousand.
In your mind’s eye, place your mother in the seat at one end of the front row, and then her mother next to her and so on – until you have filled the place with 2,000 generations of mothers and daughters.
Only the women in the front twenty or so rows would have been alive since the time when farming first began, and only those in the front six or seven rows would have lived after the earliest cities came into existence, although few of them are likely to have actually lived in cities.
You could fill five other similar theatres with earlier maternal hunter-gatherer ancestors belonging to the species Homo sapiens. All these women really existed, and they lived in a state of health, at least until the birth of a daughter.
If you were to carry out the same mental exercise imagining you were in a stadium with seats for 100,000 people, the ladies in the rows at the back would be australopithecines.