These predominantly volcanic peaks further simplify the model by their age and arrangement around the Lake Victoria basin and proximity to the equator. The species found on Mount Kenya are by far the best model for altitudinal variation. "Dendrosenecio keniodendron" is the species which grows at the highest of altitudes, "Dendrosenecio keniensis" is found at the lower altitudes of the range where the species grows and "Dendrosenecio battiscombei" grows at the same altitudes as "D. keniensis" but in the wetter environments. The other mountains which are not tall enough to have a "big one at the top" have the two, one species for the drier land and one for the damper environments or just one because the environment is not so extreme. This simplification works extremely well as an introduction to the giant groundsel of East Africa with one exception, Kilimanjaro who has the one species that lives at the top and only one species that lives below; subspecies and varieties living in the moister environments. The communities of giant "Dendrosenecio" and giant lobelias found on these African mountains are an exceptional example of parallel or convergent evolution and repeated convergent evolution between these two groups; providing evidence that the unusual features of these plants are an evolutionary response to a challenging habitat and an environment which can be easily described for biogeographic analysis. Little variation was found in molecular phylogeny among the 40 recorded giant senecio collections (40 accessions), yet as a group they differ significantly from "Cineraria deltoidea", the closest known relative. The gametophytic chromosome number (is the number of chromosomes in each cell) for the giant "Dendrosenecio" is n = 50, and for the giant lobelias. Specifically Lobeliaceae, "Lobelia" subgenus Tupa section Rhynchopetalum it is n = 14. Only five of the 11 species of giant senecio and three of the 21 species of giant lobelia from eastern Africa remain uncounted. Although both groups are polyploid, Dendrosenecio is presumed to be decaploid (ten sets; 10x) and the Lobelia more certainly tetraploid (four sets; 4x), their adaptive radiations involved no further change in chromosome number. The cytological uniformity within each group, while providing circumstantial evidence that they descended from a single ancestor and simplifying interpretations of cladistic analyses, provides neither positive nor negative support for a possible role of polyploidy in evolving the giant-rosette growth-form.