(American Journal of Botany. ;91:0.)
© Botanical Society of America, Inc.
RECIPE: mix breadnut and dugdug to make breadfruit
Zarega et al. examine AFLP variation in cultivated and wild Artocarpus species to address the evolutionary origins and spread of breadfruit (Artocarpus altilis, Moraceae) across Oceania. Their DNA fingerprinting data reveal that breadnut (Artocarpus camansi) and dugdug (A. mariannensis) were both involved in breadfruit origins. These origins are complex, as at least two different events-vegetative propagation coupled with human selection in Melanesia and Polynesia, and introgressive hybridization in Micronesia=mwere involved. Further, the authors' data add interesting information about human migration in the Pacific.
(see p. 760)
In an uncommon approach Goldman et al. take a multiple molecular data set approach to a species-level taxonomic study of Calopogon, a small orchid genus native to wetlands, prairies, and savannas in eastern North America and the northern Caribbean. Reviewers note that it is interesting to see a comparison of AFLP with sequence and RFLP data at the species level. While the relationships of most taxa in this very detailed study are resolved, the origin and relationships of the putative hybrid hexaploid Calopogon oklahomensis remain tantalizingly elusive.
(see p. 707)
The evolution of self-pollination on islands is a well-known principle in pollination with somewhat pat explanations and few good experimental studies of why it may or may not happen. Schueller proposes two hypotheses in a study whose experimental design is able to effectively distinguish between them. The organism is well chosen: hummingbird-pollinated Nicotiana glauca (Solanceae) is a plant known to have colonized two of the California Channel Islands, subsequent to its entry into California. Schueller's substantial results should stimulate further work.
(see p. 672)
Mosses that use dung, carrion, bones, and blood-soaked soil as their substrate (and emit attractive odors from their capsules that mimic these substrates) are entomophilous, relying on insects for spore dispersal, while most mosses rely on wind. These members of the Splachnaceae are the subjects of a comprehensive study by Goffinet et al., who reconstruct their evolutionary history. The authors trace the multiple origins of entomophily, and even reversals to wind dispersal, in the Splachnaceae, in a paper that reviewers feel will be cited extensively.
(see p. 748)
