HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

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

Sanders presents an interesting and careful analysis of the life cycle of a tropical leaf-dwelling (foliicolous) lichen. The life cycles of lichenized ascomycetes are poorly known but of considerable interest, since the lichen lifestyle has been a significant strategy in ascomycete evolution. The model chosen for this study is ideal, because leaf-dwelling lichens tend to have shorter life cycles than lichens colonizing more permanent substrates. By allowing lichens to colonize plastic cover slips placed in situ, Sanders has been able to use light microscopy to observe development of Phyllophiale and its algal partner Phycopeltis from propagule germination to propagule production. (see p. 1741)

Ears vs. tassels

Again, Orr et al. make a significant contribution to the origin of maize with their SEM study of tassel and ear development in a new population of annual teosinte found in the high-altitude (2500-2750 m) Valley of Toluca, Mexico. High-altitude teosintes have been postulated as progenitors of maize. As one reviewer notes, "the maize evolution story is not solved, not really, and this is a solid paper that adds a stone to the arch." Their SEM evidence is outstanding, and the stage is beautifully set for further developmental studies of maize-teosinte hybrids that will explain the maize ear and enhance understanding of inflorescence development in the grasses. (see p.1730)

The scent of speciation

Knudsen uses the remote, patchily distributed, and highly variable Amazonian palm Geonoma macrostachys for her examination of the role of floral scent as a trait involved in the differentiation and speciation of flowering plants. She provides valuable data on intraspecific variation in floral scent and its relationship to pollinators. The very slight differentiation found in floral scent composition between different populations suggests there is sufficient gene flow between distant populations, probably maintained by strong-flying euglossine bees, with other insect groups securing pollination between near populations. (see p. 1772)

Anther antics

Freudenstein, Harris, and Rasmussen carefully and thoroughly follow the dizzying ontogenetic and phylogenetic maneuvers of the orchid anther. Anther characters have been important throughout the history of orchid classification. The authors used anatomical sections of columns to assess variation in anther and pollinium orientation and to gather new data for their reexamination of homology hypotheses. They found differences between the bent anthers in vanilloids and epidendroids, and among stacked pollen masses observed in various epidendroid and vandoid orchids. Further, interesting hypotheses are offered to explain the adaptive value of these traits in relation to pollination biology. (see p. 1747)

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