Some chart types are not scalable

Peter Cock sent this Venn diagram to me via twitter. (Original from this paper.)

For someone who doesn't know genetics, it is very hard to make sense of this chart. It seems like there are five characteristics that each unit of analysis can have (listed on the left column) and each unit possesses one or more of these characteristics.

There is one glaring problem with this visual display. The area of each subset is not proportional to the count it represents. Look at the two numbers in the middle of the chart, each accounting for a large chunk of the area of the green tree. One side says 5,724 while the other say 13 even though both sides have the same areas.

In this respect, Venn diagrams are like maps. The area of a country or state on a map is not related to the data being plotted (unless it's a cartogram).

If you know how to interpret the data, please leave a comment. I'm guessing some kind of heatmap will work well with this data.