Abstract Detail



Macroevolution

Benitez-Villaseñor, Adriana [1], Magallon, Susana [2], Marten, Silvana [3].

A systematic review of secondary pollen presentation in angiosperms: shared morphological traits and pollination systems.

The separation of reproductive functions in the flower has allowed complex mechanisms in which pollen grains are transferred from anthers, where they are produced, to floral organs such as the style or perianth, where they are displayed to pollinators. This mechanism, named secondary pollen presentation, involves a fixed floral structure and morphological synorganization of organs within and among whorls to consistently achieve pollen transfer and display. Secondary pollen presentation occurs in several distantly related lineages (e.g., Asteraceae, Papaveraceae, Fabaceae, Hidrocharitaceae), suggesting that it originated repeatedly and independently during angiosperm evolution. Nevertheless, the structural and morphological traits associated with secondary pollen presentation, their correlation and distribution across angiosperms, are not well understood. An increased understanding would help us to propose possible structural and morphological precursors underlying the evolutionary history of this complex attribute. In this study, we present a systematic review that documents independent floral characters associated with secondary pollen presentation and record their distribution across families. We also evaluated the association between pollen presentation and pollination syndromes. We found that although families with secondary pollen presentation are not phylogenetically related, they present a constant suite of characters, including protandrous flowers and introrse anthers; secondary pollen presentation also occurs in species with different pollination systems. The acquisition of these floral attributes may be part of a canalization process, that results in a complex and highly integrated functional attribute.


1 - Universidad Nacional Autonoma de Mexico, Posgrado en Ciencias Biologicas, 3er Circuito de Ciudad Universitaria, Del. Coyoacán, México, Mexico, 04510, México
2 - Universidad Nacional Autonoma De Mexico, Instituto De Biologia, 3er Circuito De Ciudad Universitaria, Del. Coyoacan, A.p. 70-233, Mexico City, Mexico D.F., DIF, 04510, Mexico
3 - Universidad Nacional Autónoma de Mexico, Escuela Nacional de Estudios Superiores, Unidad Morelia, Antigua carretera a Patzcuaro No.8701, Exhacienda de San Jose de la Huerta, Morelia, Michoacan, 58190, México

Keywords:
Secondary pollen presentation
Pollination systems
flower morphology.

Presentation Type: Oral Paper
Number:
Abstract ID:502
Candidate for Awards:None


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