[Taxacom] more support for New Caledonian vicariance and metapopulation persistence

[John Grehan]

Angiosperms are not the only major plant group to figure prominently in New
Caledonian biogeography. The island is also home to a major diversity of
gymnosperms including one cycad and 43 species of conifers, all endemic,
and 14 conifer genera of which three are endemic. Heads notes that a
detailed, worldwide review of the conifers (Farjon & Filer, 2013) accepted
a vicariance model for the New Caledonian members. Heads also refers to a
study by Condamine et al. (2017)  where in light of the Cretaceous fossil
record for two of the endemic genera these authors concluded that ‘Many
attributes of New Caledonia’s flora, such as its high generic and familial
diversity, and the presence of numerous relict groups, would be
particularly difficult to explain by invoking long-distance dispersal . .
.[Instead], old lineages have persisted over geological time and dynamic
metapopulations surviving in situ on the ephemeral islands and atolls . .’

John Grehan