The Cannelales are basal dicots, most closely related to orders such as Magnoliales, and is often included with related orders of basal dicots in sub-class Magnoliidae. Under the older Cronquist system they are included in order Magnoliales, to which they are believed to be related.
These data indicate that angiosperms or their stem group ancestors extend back to the Early Permian, and that most basal angiosperm evolution (below the Winterales) probably occurred in the Triassic and Jurassic.
As recently as a decade ago, the Magnoliales and Winterales had been considered more basal (primitive) than the Nymphaeales, Eudicots, and Monocots; and that interpretation supported an Early Cretaceous origin for angiosperms based on Cretaceous fossils (i.e., Magnoliaceae and Winteraceae in the Barremian-Cenomanian).
On the one hand, some pre-Cretaceous angiosperms may appear to violate sequence events for the "first" appearance of organ characteristics in the Cretaceous (for example, leaf rank sequences deduced by Hickey and Doyle, 1977), but instead indicate that angiosperms could evolve and re-evolve those characteristics at different times (e.g.
Second, there is no guarantee that plant/pollinator relationships have remained the same from the origins of the angiosperms to the present.
Nevertheless, specialized relationships between bees and angiosperms are not likely to have existed prior to the common ancestor of the eudicots because extant magnoliids (monocots, Winterales, Laurales, Magnoliales, Chloranthales, Piperales, etc.) are, for the most part, not bee pollinated (Thien et al.
The eudicots have recently been estimated to be between 147 and 131 million years old based on combined fossil and DNA evidence (Wikström et al.
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