Tropical forest biodiversity is declining, but the resulting effects on key ecosystem services, such as carbon storage and sequestration, remain unknown. We assessed the influence of the loss of tropical tree species on carbon storage by simulating 18 possible extinction scenarios within a well-studied 50-hectare tropical forest plot in Panama, which contains 227 tree species. Among extinction scenarios, aboveground carbon stocks varied by more than 600%, and biological insurance varied by more than 400%. These results indicate that future carbon storage in tropical forests will be influenced strongly by future species composition.

Weinmannia (Cunoniaceae) is a woody genus of about 150 species widely distributed in the tropics and the southern temperate zone. Herbarium and living specimens were examined to determine characters for a cladistic analysis to test the monophyly of the genus and its sections. A matrix of 28 taxa and 31 morphological characters was analyzed to find the most parsimonious trees. The strict consensus cladogram supports the monophyly of the genus Weinmannia and sections Leiospermum, Weinmannia (including sect. Simplicifolia), lnspersa, and Spicata, but section Faseictilata is paraphyletic with respect to a highly derived section Weinmannia. Section Leiospermum from the South Pacific is the sister taxon to the rest of the genus. Some of the most parsimonious trees support a monophyletic clade from Madagascar of sections lnspersa and Spicata, but this node is unresolved in the strict consensus tree. Although the deep nodes of the phylogeny are not well supported, and few evolutionary interpretations are ventured, it appears that dioecy has arisen independently at least three times in the genus. The method and theory used to analyze variation in inflorescence architecture, which emerges from the metameric construction of plants and positional homology, are emphasized. The cladistic coding of positional characters and the tracing of their evolution on the cladogram are a study in heterotopy. i.e., evolutionary change in the position of development. Heterotopic evolution in the inflorescence is common in Weinmannia, suggesting a role for an evolutionary-developmental process that has typically been overlooked in favor of heterochrony.

Cunoniaceae are a family of shrubs and trees with 27 genera and ca. 335 species, mostly confined to tropical and wet temperate zones of the southern hemisphere. There are several known issues regarding generic limits, and the family also displays a number of intriguing long-range disjunctions. METHODS:We performed a phylogenomic study using the universal Angiosperms353 probe set for targeted sequence capture. We sampled 37 species covering all genera in the Cunoniaceae, and those in the three closely related families of the crown Oxalidales (Brunelliaceae, Cephalotaceae, and Elaeocarpaceae). We also performed analyses for molecular dating and ancestral area reconstruction. RESULTS:We recovered the topology (Cunoniaceae, (Cephalotaceae, (Brunelliaceae, Elaeocarpaceae))) and a well-resolved genus-level phylogeny of Cunoniaceae with strongly supported clades corresponding to all previously recognized tribes. As previously suspected, the genera Ackama and Weinmannia were recovered as paraphyletic. Australasia was inferred as the likely ancestral area for the family. CONCLUSIONS:The current distribution of Cunoniaceae is best explained by long-distance dispersal with a few possible cases of Australasian-American vicariance events. Extinctions may have been important in determining the mostly Oceanian distribution of this family while some genera in the tribe Cunonieae and in New Caledonia have undergone recent bursts of diversification. New generic diagnoses, 80 new combinations, and one new name are provided for a recircumscribed Ackama (including Spiraeopsis), a much smaller Weinmannia (mostly New World), and a resurrected Pterophylla to accommodate Old World taxa previously in Weinmannia.

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The macrofossil record of the plant family Cunoniaceae in Australia is summarised and reviewed where necessary by using detailed studies of the morphology of extant genera. Eleven of the 26 Cunoniaceae genera are represented in the Australian macrofossil record and include leaves and leaf fragments, foliar cuticle and reproductive structures, and range from Late Paleocene to Quaternary in age. Macrofossils show