within 3 months); and during the subsequent 18 years she was pregnant a total of 11 more times.On average, there were 500 days between each of the first nine pregnancies, as shown in the first graph.
The children of this marriage have recently been discussed in the book by Tim Berra (Darwin and His Children: His Other Legacy).
This book discusses Darwin's children mainly in the context of Darwin's own life.
Unfortunately, it does not delve much into his personal relationship with either them or his wife, Emma. In particular, the book fails to draw any inference from the obvious fact that there were 10 of these children, plus two possible miscarriages.
Instead, I will provide my own analysis of the situation.
Background Charles and Emma married on 29 January 1839, when Charles was 29 years and 11 months old and Emma was 30 years and 8 months old.
This is pretty late to be starting a family, although not necessarily unusual, and it does have an influence on the calculations.
Emma realized during the following April that she was pregnant (ie.
However, obviously we do learn indirectly about a certain part of Mr Darwin's private life.
After all, one does not get a woman pregnant accidentally (no matter what your friends try to tell you) -- there are certain biological procedures that you need to go through, and it is fairly difficult to carry these out accidentally.
Clearly, Charles and Emma were familiar with this particular activity, and carried it out successfully on numerous occasions. We know the minimum number, but what about the average rate, for example?
The Darwin cottage industry has apparently produced speculations about his sex life before (see Wikipedia), but I have not read about them.