A key concept for Darwinism is adaptation. Traits are identified that confer survival and reproduction advantages to an organism. These traits are supposed to experience selection pressures that drive adaptive change and speciation. Consequently, traits are of central importance for theories of evoplutionary transformation, as is also time. However, when contemplating the flowering plants, even Darwin found them difficult to reconcile with his theory. Writing to J.D. Hooker in 1879, he described the evolutionary success of angiosperms as “an abominable mystery“. He was troubled by the abrupt origin and extraordinarily rapid diversification of flowering plants in the mid-Cretaceous.
“The answer to whether any of the above traits are consistent predictors of diversity of a given rate of lineage growth depends more upon geographical rather than biological traits, such as geographical extent (i.e., total area occupied by a clade) and climate. Others have suggested that neither geographical nor biological traits determine diversification on their own but rather certain traits (or combinations thereof) may stimulate diversification within a particular geographical context.”
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