The biogeographical history of the mulberry family (Moraceae) was investigated using phylogenetic inferences from nuclear and chloroplast DNA, molecular dating with multiple fossil calibrations, and independent geological evidence. The Moraceae are centered in the tropics which has invited the hypothesis that the family has Gondwanan origins and extant distribution is the result of vicariance due to the break-up of Gondwana. However, the cosmopolitan distribution of Moraceae suggests a more complicated biogeographical history. The timing and location of Moraceae diversiWcation also bears on the origin of the Wg pollination mutualism, a model for the study of coevolution and specialization. Recent molecular dating of pollinating Wg wasps suggested that an ancient Gondwanan origin coupled with vicariance and dispersal could account for the present day distribution of the mutualism. Here, we provide the Wrst assessment of this hypothesis based on dating of Wgs and their relatives. Minimum age estimates suggest that the Moraceae had diversiWed by at least the mid-Cretaceous and major clades including the Wgs may have radiated during the Tertiary after the break-up of Gondwanaland. Molecular evidence together with Eurasian fossils suggest that the early diversiWcation of Moraceae in Eurasia and subsequent migration into the southern hemisphere is at least as plausible as the Gondwanan hypothesis. These Wndings invite a reevaluation of the biogeography of Wg pollination and highlight the need for incorporating multiple sources of evidence in biogeographical reconstructions. 

The majority of species in the mulberry family (Moraceae) are figs (Ficus), marked by a specialized inflorescence (syconium) and an obligate mutualism with pollinating fig wasps. Because of the unique morphology of the syconium, it has been difficult to investigate the evolutionary position of the fig. We sequenced the chloroplast gene ndhF to examine relationships in Moraceae and to elucidate shifts in reproductive traits. The reclassification of tribes is warranted, and the limits of Artocarpeae, Moreae, and Castilleae are revised to reflect evolutionary relationships. The results point to ancestral dioecy in Moraceae and multiple origins of monoecy, androdioecy, and gynodioecy. Ancestral wind pollination gave way to insect pollination at least twice. Strong support for the sister-group relationship of a revised Castilleae with Ficus suggests that entomophily and involucral bracts encircling the flowers preceded the evolution of the syconium. Bracts surround flowers in Castilleae only during early development, but in Ficus the involucre and the receptacle enclose the fruit as well. Molecular dating suggests that fig pollination is at least 80-90 million years old. The diversity of Ficus relative to its sister group is a likely consequence of ancient specialization and cospeciation with pollinating fig wasps.

The large and diverse genus Penstemon (ca. 271 species) is endemic to North America and has been divided into six subgenera primarily based on anther dehiscence patterns. Species of Penstemon are known to be pollinated by a variety of insects (hymenopterans, lepidopterans, dipterans) and hummingbirds. Nucleotide sequence data from ITS and two noncoding regions of chloroplast DNA were used to reconstruct the phylogeny of Penstemon. Trees generated from nuclear and chloroplast DNA sequences are incongruent, which is probably the result of hybridization, and not fully resolved, which is likely due to a rapid evolutionary radiation. Penstemon represents a recent continental radiation where speciation has resulted primarily from evolutionary adaptations to ecological niches such as pollinator specialization. The results from these analyses show that the current circumscription of subgenera and sections needs revision to reflect more closely the evolutionary relationships of species. Specifically, species in subgenera Saccanthera, Habroanthus, and Penstemon are polyphyletic. These results also confirm the independent origin of hummingbird floral morphology in 10 clades.

Cannabis sativa L. (Cannabaceae) is one of the earliest known cultivated plants and is important in the global economy today as a licit and an illicit crop. Molecular markers distinguishing licit and illicit cultivars have forensic utility, but no direct comparison of hemp and marijuana amplified fragment length polymorphism (AFLP) has been made to date. Genetic variation was surveyed in three populations of fiber hemp and a potent cultivar of marijuana using AFLP markers. Ten primer pairs yielded 1206 bands, of which 88% were polymorphic. Eighteen bands represented fixed differences between all fiber populations and the drug cultivar. These markers have practical utility for (1) establishing conspiracy in the cultivation and distribution of marijuana, (2) identifying geographic sources of seized drugs, and (3) discriminating illegal, potent marijuana cultivars from hemp where the cultivation of industrial hemp is permitted.

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Spatially variable natural selection along gradients of aluminum and phosphate ion concentrations likely accounted for both outliers. These results shed light on some of the genetic components comprising the extended phenotype of this ecosystem, as well as highlight ecotones as fruitful study systems for the detection of adaptive genetic variants.

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