Population (Step) Pyramids: Why Did the Nephites Change So Quickly?

Two countries can have the exact same population but a very different age distribution.  A population pyramid is a graphic way of showing what a population looks like.  Many modern countries have population pyramids that are more like columns that taper at the top.  Less developed societies historically looked like the Afghanistan pyramid above; a high birth rate and a high death rate meant the population was always on average very young.

We don’t know what the Nephite and Lamanite population pyramids looked like.  It’s possible that the Nephite modernity affected birth rates, that’s a pretty common thing to happen in a society’s modernity and the Nephites do seem to be vastly outnumbered much of the time.   On the other hand there is an absence of Book of Mormon prophets condemning birth limitations which is at least some evidence.  And in historical societies undergoing modernity, the low birth rates were more concentrated in the upper classes and did not penetrate the lower classes and rural people (and they were still mostly rural people) as much as in our society.

So although we don’t know what their population pyramids looked like, we can at least speculate that they were something like a typical pre-industrial revolution agricultural society with a lot more youth than middle aged or old people.

If so, this helps explain why the Nephite society was so variable.  And also the Lamanite society, its not as obvious because Mormon isn’t as interested in it but the Lamanites also are constantly making radical changes.

Five or ten years after a big event, the majority of the Nephite adults might have been kids back then and only have vague memories of it.

Here’s a population pyramid for Nigeria, again fairly typical for a less advanced country.

The average age in Nigeria at the time of this graph was less than 18 years old.  That means that 10 years after an event, the majority of your adults weren’t adults when it happened.  Thirty years later–say, the distance between the miracle of Christ’s birth and his coming to the Nephites/Lamanites–the great majority of the adults weren’t even born when the miracle happened.  It’s all ancient history.  Everything from the Creation to Moses to Lehi to Captain Moroni to the miracle of the day without a night are all a smudge of stuff that happened a long long time ago.