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Langenberger and Davis describe three phases of nectar production in the tiny, long-lived flowers of caraway. Sampling many minute volumes of very concentrated nectar, they found that 30% of total nectar is produced by male-phase flowers and 70% by female-phase flowers and that there is a quiescent stage between male and female phases when no nectar is produced. The paper includes a nice experiment in which paired florets were sampled during the female phase only or throughout both phases, showing that nectar reabsorbed after the male phase did not contribute to larger volumes in the female phase. Further, the authors' research revealed that chemical composition differs in male- and female-phase nectar producd by the same glands. (see p. 1588)

Testing rewardlessness

Smithson tackles the difficult question of why so many orchids lack rewards in their flowers. The well-designed, well-described, and easily replicated experimental methodology tests the effect of artificial nectar supplementation on pollinator behavior and various measures of reproductive success in both natural populations and potted orchids presented to foraging bees. Her results weaken some of the usual explanations for the evolution of deceitful flowers in orchids (the geitonogamy hypothesis) and place emphasis on the role of pollinator behavior. (see p.1579)

Monitoring mysterious moonworts

Botrychium (moonworts) are rare and small but a surprising number of people are looking for them. These ``goblin-like ferns'' are of considerable scientific interest because of questions regarding their phylogeny (whether they are ferns or pre-gymnosperms), and their seemingly mysterious ecology (disappearance underground for multiple years). A reviewer comments that authors Johnson-Groh and Lee are to be commended for quantifying what most botanists never see. The phenology presented sets a new standard of thorough observations in order to capture the turnover of these enigmatic plants. The authors' census data indicate that the largest, and most easily counted, plants were found at the end of the growing season when most of the plants in the population had senesced, resulting in a false estimate of the population size. (see p. 1624)

Accomodating intron complexity

Chloroplast introns are fast becoming the workhorses of low-level phylogenetic sequence analysis in plants. In light of recent experimental data on intron structure and function, [chKelchner recommends we revise our conventional notions of group II intron evolution and how intron sequences should be used when estimating evolutionary relationships. Kelchner reviews what is known about intron structure and function, presents data illustrating the effect of structure conservation on intron substitution patterns, and advocates a new paradigm for the phylogenetic analysis of intron sequences. (see p. 1651)

This Article Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Search for Related Content