It's an impressive effort, although it's missing the first Linux I regularly used: Tom Oehser's tomsrtbt (http://www.toms.net/rb/), a single-floppy release aimed at system rescue.
Highlighting the lineage aspect, however, loses useful context information. For example, Robert Shingledecker was a significant part of the development of Damn Small Linux for five years before he started the Tiny Core Linux project. While there's no commonality in the distribution-specific code that I'm aware of, and hence no reason for a graphic connection on the chart, I think it's safe to say that Tiny Core's design is a continuation of Shingledecker's thinking on what makes a good minimal Linux.
Highlighting the lineage aspect, however, loses useful context information. For example, Robert Shingledecker was a significant part of the development of Damn Small Linux for five years before he started the Tiny Core Linux project. While there's no commonality in the distribution-specific code that I'm aware of, and hence no reason for a graphic connection on the chart, I think it's safe to say that Tiny Core's design is a continuation of Shingledecker's thinking on what makes a good minimal Linux.