دورية أكاديمية

Anther Evolution: Pollen Presentation Strategies When Pollinators Differ.

التفاصيل البيبلوغرافية
العنوان: Anther Evolution: Pollen Presentation Strategies When Pollinators Differ.
المؤلفون: Castellanos, Maria Clara, Wilson, Paul, Keller, Sarah J., Wolfe, Andrea D., James D.6 Thomson
المصدر: American Naturalist; Feb2006, Vol. 167 Issue 2, p288-296, 9p, 2 Charts, 1 Graph
مصطلحات موضوعية: ANTHER, STAMEN, POLLEN, POLLINATORS, PENSTEMONS, HYMENOPTERA, PLANT morphology, HUMMINGBIRDS, BIOLOGICAL evolution
مستخلص: Male-male competition in plants is thought to exert selection on flower morphology and on the temporal presentation of pollen. Theory suggests that a plant's pollen dosing strategy should evolve to match the abundance and pollen transfer efficiency of its pollinators. Simultaneous pollen presentation should be favored when pollinators are infrequent or efficient at delivering the pollen they remove, whereas gradual dosing should optimize delivery by frequent and wasteful pollinators. Among Penstemon and Keckiella species, anthers vary in ways that affect pollen release, and the morphology of dried anthers reliably indicates how they dispense pollen. In these genera, hummingbird pollination has evolved repeatedly from hymenopteran pollination. Pollen production does not change with evolutionary shifts between pollinators. We show that after we control for phylogeny, hymenopteran-adapted species present their pollen more gradually than hummingbird-adapted relatives. In a species pair that seemed to defy the pattern, the rhythm of anther maturation produced an equivalent dosing effect. These results accord with previous findings that hummingbirds can be more efficient than bees at delivering pollen. [ABSTRACT FROM AUTHOR]
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قاعدة البيانات: Complementary Index