The details for this subtopic are still under development. Possible questions that could be addressed in this subtopic include:
- What drives speciation (e.g., reproductive isolation) and how stable is a species through time?
- What is a diagnostic character and how important is it for the stability of species and its isolation from other species? (Taxonomic boundaries)
- When is a species extinct (i.e., final discontinuity)?
- How can phenotypes be stable for tens to hundreds of millions of years (e.g., morphological stasis)?