Results 181 to 190 of about 4,342 (221)

Cryptic dioecy in flowering plants

Trends in Ecology & Evolution, 1991
In some dioecious plant species, mates and/or females have large and presumably costly opposite-sex structures that are sterile. This is termed 'cryptic dioecy'. Several new cases of cryptic dioecy have recently been studied. They may give information about the minimal requirements for the evolution of separate sexes from hermaphroditism, because the ...
S S, Mayer, D, Charlesworth
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Diversification, dioecy and dimorphism in schistosomes

Trends in Parasitology, 2006
In addition to causing one of the great neglected diseases of the world, schistosomes have unusual biological features that further command attention, including their habit of living in the blood of their hosts and the presence of separate, dimorphic sexes.
Eric S, Loker, Sara V, Brant
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RECURRENT EVOLUTION OF DIOECY IN BRYOPHYTES

Evolution, 2012
The origin and maintenance of separate sexes (dioecy) is an enduring evolutionary puzzle. Although both hermaphroditism and dioecy occur in many diverse clades, we know little about the long-term evolutionary consequences of changing sexual system. Here we find evidence for at least 133 transitions between sexual systems in mosses, representing an ...
Stuart F, McDaniel, John, Atwood, J Gordon, Burleigh   +2 more
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Dioecy inHonkenya peploides var.major (Caryophyllaceae)

The Botanical Magazine Tokyo, 1992
Sexual difference and pollination system inHonkenya peploides var.major were investigated. The present analyses indicate that sex expression of this plant is functionally dioecious, rather than androdioecious, as described previously. Its flowers are largely pollinated by small bees, hover-flies, flies, and ants.
Takahiro Tsukui, Takashi Sugawara
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Animal Dispersal Dynamics Promoting Dioecy over Hermaphroditism

The American Naturalist, 2007
Because of the separation of sexual function to male and female individuals, dioecious species have fewer pollen and seed bearers and thus experience disadvantages due to increased aggregation of reproductive function. Because of this disadvantage, models predict that dioecious females must have substantially more than twice the fecundity of ...
Jana C, Vamosi, Yu, Zhang, William G, Wilson   +2 more
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Synchronized dichogamy and dioecy in neotropicalLauraceae

Plant Systematics and Evolution, 1984
In hermaphrodite neotropicalLauraceae a highly evolved dichogamous system is present which represents a kind of temporal dioecy. This system involves the existence of two flower morphs which are characterized by reciprocal phases of receptivity of the stigmas and pollen release.
Klaus Kubitzki, Holger Kurz
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Dioecy inMikania (Compositae:Eupatorieae)

Plant Systematics and Evolution, 1991
For the first time dioecy inMikania and in the tribeEupatorieae is described and discussed. The condition is known only in members of theMikania swartziana Griseb. complex, a group of eight species, all endemic to the Greater Antillean Islands of Cuba, Hispaniola, and Jamaica.
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Evolution of Dioecy in Saurauia (Dilleniaceae)

Annals of the Missouri Botanical Garden, 1984
Saurauia veraguensis in Costa Rica is morphologically androdioecious but functionally dioecious. Both staminate and pistillate flowers bear pollen. The pollen in the staminate flowers is tricolporate, and smaller than the inaperturate pollen borne by the pistillate flowers.
W. A. Haber, K. S. Bawa
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Cryptic dioecy in Mammea (Clusiaceae)

Plant Systematics and Evolution, 2004
The flowers of Mammea (Clusiaceae) have been reported to be androdioecious, a rare condition in the angiosperms. Pollen from eight taxa from most of the geographic range of the genus was examined to clarify the type of flowers, and thus the breeding system, of the genus. In six of these taxa pollen from both morphologically perfect and male flowers was
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Dioecy in South American Deprea (Solanaceae)1

BIOTROPICA, 2000
ABSTRACTDioecy in the Solanaceae is rare, occurring in < 1 percent of the species worldwide and known in only two species from South America. We report the occurrence of cryptic dioecy in the Neotropical genus Deprea. Studying herbarium material of the Venezuelan endemic D.
Neil W. Sawyer, Gregory J. Anderson
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