Fig 2. The total number of descendent devices connected to each ancestral predicate (n = 400) by chains of substantial equivalency.

Ancestral predicates are grouped according to the time period in which they entered the market (bar color) to highlight that the skewed distribution in the number of descendent devices is not an artefact of the time available for ancestral predicates to accumulate descendants. Mersilene Surgical Mesh had the largest number of descendent devices and is highlighted (see Fig 3 for the ancestral history of this device).