Another plot shows different patterns in the data. This plot show the Year of publication (y-axis) plotted against the linear taxonomic sequence (x-axis). Several interesting patterns are present here.
The importance of the ordering on the X-axis is relatively unimportant, though a few patterns result from it, and will be disucssed below.
The most striking feature is the apparent "gap" that is in the lower part of the plot. This "gap" starts at 1790, and extends to 1815. The apparent "floor" of the gap results from the large number of taxa described by Gmelin in 1788, 1789. If the Gmelin taxa (which are mostly Latham taxa that Gmelin applied binomena to) are removed, the "gap" blends in with the rest of the pre-1815 data. The "ceiling" of the gap starts with the large number of taxa described by Vieillot, but it is clear that this pattern of activity continued largely without change, and is not the result of one individual's efforts.
This "gap" does not seem to be present in the other taxonomic groups I have investigated, and that have enough data to reveal the presence of a possible "gap". (I have looked at mammals, fish, lichens, among others).
In the middle portion of the lower portion of the plot, there is a relative paucity of points. This region represents the New World Thamnophilids. These birds evidently were not extensively collected by early collectors, not recognized as distinct taxa by early taxonomists, or both.
