(American Journal of Botany. ;89:0.)
© Botanical Society of America, Inc.
Triurids in Jersey
Gandolfo, Nixon, and Crepet assess fossil flowers, approximately 90 million years old (Turonian, Upper Cretaceous), from the flora of the Raritan Formation, New Jersey, USA. After cladistic analysis they assign the three species to the completely saprophytic, mostly tropical Triuridaceae, making these fossils the earliest unequivocal evidence of monocots, and perhaps the earliest evidence of a saprophytic/mycotrophic habit in angiosperms. Further, one can infer that Upper Cretaceous New Jersey enjoyed a tropical to subtropical climate.
(see p. 1940)
Magallón and Sanderson search for explanations of the conflicting topologies involving phylogenetic relationships among five seed plant lineages while presenting both parsimony and maximum likelihood analyses of a substantial amount of new data from two chloroplast genes, psaA and psbB. Tackling this difficult problem in an unbiased manner, they combine sophisticated analyses with discussions of the effect of heterogeneous rates of molecular evidence and thorough consideration of morphology that may support or refute alternative relationships.
(see p. 1991)
Martre et al. pose novel questions about soil rockiness. They take on the hard and seemingly impenetrable topic of assessing how soil rockiness is correlated with plant growth, comparing the responses of the succulent Agave deserti and the bunchgrass Pleuraphis rigida in a study well designed for the analysis of both the effects of soil texture on root systems and the effects of soil-root interaction on aboveground plant growth and water use. If researchers have ignored the role of rocks in fieldwork, they may want to change their approach as they excavate root systems.
(see p. 1933)
Two papers in this issue advance current research aimed at elucidating specific phylogeographic processes that have shaped the genetic patterns of alpine plants of the European Alps and the Arctic as species survived the Ice Age in peripheral refugia or within the ice sheet on nunataks. Stehlik uses both traditional phylogeographic methods and nested clade analysis to uncover the glacial history of Rumex nivalis and Tribsch, Schönswetter, and Stuessy use DNA fingerprinting (AFLP) to track Saponaria pumila.(see
p. 2007
and
p. 2024
)
