Phylogeny and Historical Biogeography of Geraniaceae in Relation to Climate Changes and Pollination Ecology

Abstract

Chloroplast (trnL–F and rbcL) sequences were used to reconstruct the phylogeny of Geraniaceae and Hypseocharitaceae.
\nAccording to these data Hypseocharitaceae and Geraniaceae are monophyletic. Pelargonium and Monsonia are sisters to the largest clade of
\nGeraniaceae, formed by Geranium, Erodium and California. According to molecular dating and dispersal-vicariance analysis, the split of the
\nstem branches of Geraniaceae probably occurred during the Oligocene, in southern Africa or in southern Africa plus the Mediterranean area.
\nHowever, their diversification occurred during the Miocene, coinciding with the beginning of major aridification events in their distribution
\nareas. An ancestor of the largest clade of Geraniaceae (Geranium, Erodium, and California) colonised a number of habitats in the northern
\nhemisphere and in South American mountain ranges. In summary, the evolution of the Geraniaceae is marked by the dispersal of ancestors
\nfrom Southern Africa to cold, temperate and often disturbed habitats in the rest of world, where only generalist pollination and facultative
\nautogamy could ensure sufficient seed production and survival.