The oldest known fossils of members of Asteraceae are pollen grains from the Late Cretaceous of Antarctica, dated to ∼76-66 Mya (Campanian to Maastrichtian) and assigned to the extant genus Dasyphyllum [REF].
It is still unknown whether the precise cause of their great success was the development of the highly specialised capitulum, their ability to store energy as fructans (mainly inulin), which is an advantage in relatively dry zones, or some combination of these and possibly other factors [REF].