A type of animated, interactive graphics was famously presented to the world by Hans Rosling of the Gapminder Foundation in a TED talk. The bubble plots that were presented clearly showed changes for several variables over time. Paul Murrell produced an animated ggplot2 plot based on the Gapminder bubble plots. This demonstration is perhaps more informative as it separates countries into different continents and draws a separate panel for each continent. In doing so we can more easily see the variation within continents.
We can see that over time, for all continents, the general trend is that as the number of children per woman decreases, it is associated with an increase in life expectancy. What is interesting is how it is possible to observe significant events such as wars occurring within each continent.