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Showing 1 to 19 of 19 for “"breeding systems"”.
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Maternal investment tactics in cooperative breeding systems
… carer contributions within a single stage of a breeding attempt, neglecting the potential for investment during earlier stages to influence later care decisions. Typically, mothers have much greater control than other carers over the number and quality of offspring, and hence by altering her …
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A molecular and evolutionary study of skua breeding systems
… and the brown skua (C. lonnbergi). The breeding distribution of the former, is restricted to the Antarctic continent and nearby islands, while the latter has a circumpolar distribution which extends northward from the Antarctic Peninsula and includes many of the Southern Ocean islands. …
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Breeding Systems, Adaptation and Evolution: An Experimental Approach Using Ciliates
Made available in DSpace on 2014-12-12T01:27:37Z (GMT). No. of bitstreams: 1 7212317.pdf: 2465442 bytes, checksum: f6d86d3e28d3ebb25d5cc1743b733680 (MD5) Previous issue date: 1971
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Variation in breeding systems and consequences for reproductive traits in Erica
… similar changes occur in Erica. I thus analysed breeding systems in Erica in relation to floral traits, pollinators, and fire survivals strategies. Seed and fruit set data obtained from hand-pollination treatments suggested that self- fertilization occurs rarely. Autonomous selfing did not …
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Breeding systems and pistil structure in the family proteaceae / Merran Lisa Matthews.
This study aimed to broaden understanding of breeding systems in Australian Proteaceae and to study the optimum requirements for promotion of seed germination in two lesser researched genera with horticultural potential, Dryandra quercifolia and Dryandra formosa. The timing and pattern of stigma …
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The Ecology of Sexual and Apomictic Reproduction in Antennaria Parlinii Gaertner (Apomixis, Plant Breeding Systems, Evolution)
Differences in habitat and geographic distributions of sexually and asexually reproducing species are often attributed to differences in relative colonizing and competitive abilities. In this thesis, fitness components that influence colonizing and competitive ability are compared in an herbaceous …
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Plant-pollinator relationships of culturally significant food and medicine plants in the Great Lakes Region
… plant species. Availability of information on breeding systems and important pollinators is crucial information for management of plant species, especially if a plant species is experiencing population declines (e.g. at-risk, endangered). A literature review was conducted to determine what is …
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The Evolution And Reproductive Ecology Of Oenothera (Onagraceae)
… in reproductive traits such as pollination and breeding system, features that have been important in angiosperm diversification. These systems are evolutionarily labile; they easily shift between different states. These different reproductive traits may shift in a concerted fashion; therefore, a …
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Reproductive biology and ex situ conservation of the genus Restrepia (Orchidaeae)
… has not been described, and its pollination and breeding systems have not been investigated. The aim of this investigation was, therefore, to add to existing knowledge so that the resultant data could be used to facilitate ex situ conservation initiatives. A detailed electron microscopy study …
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The Prince or the Depauperate? Population Genetics of the Rare, Closed-flower Erica occulta
Understanding breeding systems and gene flow is important for the conservation of rare species. Despite this, they remain relatively unknown for Fynbos species. Erica occulta is a rare, dull, closed-flower Erica that is restricted to the few limestone cliffs near Groot Hagelkraal on the Southern …
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Genetic Diversity and Camptothecin Variation in Camptotheca Decaisne
… to be higher than in other species with similar breeding systems. All populations were therefore genetically distinctive and each should be considered as a management unit. The high level of genetic structure among populations indicates differentiation due to founder events and/or genetic drift …
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Effects of Anthropogenic Light and Noise on Anuran Breeding Behavior
… light at night and anthropogenic noise on anuran breeding systems in eastern Texas. Specifically, this study investigated whether (1) artificial light and anthropogenic noise altered calling behavior in male anurans, (2) artificial light influenced male call site selection, and (3) artificial …
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Method development and proteomic profiling of boar seminal plasma using mass spectrometry-based workflows
… precision, and the use of low fertile boars in breeding systems is prominent. Using mass spectrometry in fertility studies has gained momentum in the race for new markers of fertility and semen cryopreservation. Therefore, the aim of this study was to develop and optimise a mass …
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The reproductive biology of four geoflorous Protea species (Proteaceae)
Pollination systems of previously unstudied plant species are often inferred from floral traits that are shared among unrelated plant taxa. However, these ‘pollination syndromes’ are often not reliable predictors of the primary pollinator of a plant species, and may in fact represent adaptations to …
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The Effect of Selection on Egg Production in Single Comb White Leghorn Fowl
The practical value of any system of breeding for egg production must be demonstrated first to be appreciated by the average poultryman. High egg yield has been found by several workers to be due to the combined influences of early sexual maturity, non-winter pause, high intensity, non-broodiness …
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Sperm Competition and the Function of Masturbation in Japanese Macaques (Macaca fuscata)
… species that exhibit a multi-male multi-female breeding system than to species living in monogamous, one-male units, solitary or dispersed breeding groups. This result is in direct contrast to established theories of sperm competition, which predict that species with a higher risk of sperm …
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Dissecting the evolutionary forces shaping sex chromosome evolution in papaya
… the autosome, contrasting other young chromosome systems. The autosomal regions and male Y chromosome are evolving neutrally, but the HSY is experiencing strong positive selection due to a selective sweep during human domestication. This is the first case where human domestication resulted in the …
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Population dynamics and reproductive ecology of the gynodioecious prairie species Lobelia spicata Lam. (Campanulaceae)
… prairie species found throughout Illinois. Its breeding system, gynodioecy, is relatively rare, and is characterized by having female and hermaphrodite plant morphs coexisting within populations. Although some data on the reproductive ecology of L. spicata has been gathered, the population and …