Open Access. Powered by Scholars. Published by Universities.®

Evolution Commons™

Open Access. Powered by Scholars. Published by Universities.®

Population Biology

Institution
Keyword
Publication Year
Publication
Publication Type

Articles 151 - 155 of 155

Full-Text Articles in Evolution

The Pollination Biology And Mating System Of A Peripheral Population Of Witheringia Solanacea (Solanaceae), Timothy Miller Jan 2008

The Pollination Biology And Mating System Of A Peripheral Population Of Witheringia Solanacea (Solanaceae), Timothy Miller

Honors Theses

Pollinator visitation rates over the life of a flower are determined by pollinator abundance and floral longevity. If flowers are not visited frequently enough, pollen limitation may occur, favoring the evolution of self-compatibility (SC). In plant species with varying SC levels, central populations often are self-incompatible (SI) and peripheral populations are SC. Witheringia solanacea (Solanaceae) is a species that follows this trend with the exception of one population in the Monteverde Cloud Forest Reserve, which is peripheral yet SI. I investigated this population using multiple techniques including floral bagging, pollinator observations, microsatellite analysis, and floral longevity manipulations. My results confirmed …

Go to article

Simpler Mode Of Inheritance Of Transcriptional Variation In Male Drosophila Melanogaster, Marta Wayne, Marina Telonis-Scott, Lisa Bono, Lawrence G. Harshman, Artyom Kopp, Sergey V. Nuzhdin, Lauren Mcintyre Nov 2007

Simpler Mode Of Inheritance Of Transcriptional Variation In Male Drosophila Melanogaster, Marta Wayne, Marina Telonis-Scott, Lisa Bono, Lawrence G. Harshman, Artyom Kopp, Sergey V. Nuzhdin, Lauren Mcintyre

Lawrence G. Harshman Publications

Sexual selection drives faster evolution in males. The X chromosome is potentially an important target for sexual selection, because hemizygosity in males permits accumulation of alleles, causing tradeoffs in fitness between sexes. Hemizygosity of the X could cause fundamentally different modes of inheritance between the sexes, with more additive variation in males and more nonadditive variation in females. Indeed, we find that genetic variation for the transcriptome is primarily additive in males but nonadditive in females. As expected, these differences are more pronounced on the X chromosome than the autosomes, but autosomal loci are also affected, possibly because of X-linked …

Go to article

Decreased Reproductive Investment Of Female Threespine Stickleback Gasterosteus Aculeatus Infected With The Cestode Schistocephalus Solidus: Parasite Adaptation, Host Adaptation, Or Side Effect?, Eric T. Schultz, Michelle Topper, David C. Heins Jan 2006

Decreased Reproductive Investment Of Female Threespine Stickleback Gasterosteus Aculeatus Infected With The Cestode Schistocephalus Solidus: Parasite Adaptation, Host Adaptation, Or Side Effect?, Eric T. Schultz, Michelle Topper, David C. Heins

EEB Articles

Parasitic infections may cause alterations in host life history, including changes in reproductive investment (absolute amount of energy allocated to reproduction) and reproductive effort (proportion of available energy allocated to reproduction). Such changes in host life history may reflect: 1) a parasite tactic: the parasite adaptively manipulates energy flow within the host so that the host is induced to make a reduction in reproductive effort and reproductive investment, making more energy available to the parasite; 2) no tactic: there is no change in host reproductive effort and reproductive investment simply decreases as a side effect of the parasite depleting host …

Go to article

Do Timing And Pattern Of Myogenesis Correlate With Life History Mode In Anurans?, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice Dec 2000

Do Timing And Pattern Of Myogenesis Correlate With Life History Mode In Anurans?, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice

Biology Faculty Publications

The timing and pattern of myogensis varies among anurans that have been studied and the different patterns may provide useful phylogenetic information. Specific myogenic markers have been described (Muntz, 1975; Kielbowna, 1981; Boudjelida & Muntz, 1987; Radice et al., l989) and they can provide information on evolutionary changes for closely related lineages within a clade. For example, we previously compared first appearance of a muscle-specific protein, first twitch of axial muscle, onset of multinucleation within axial myotome, and first heartbeat in two pipid genera (Smetanick, et al., 1999). We found that although the timing of myogensis differed, the sequence of …

Go to article

Evaporative Water Loss In Two Northwest Snakes: Pituophis Catenifer And Crotalus Viridis, Donald R. Woolery Jun 1971

Evaporative Water Loss In Two Northwest Snakes: Pituophis Catenifer And Crotalus Viridis, Donald R. Woolery

All Master's Theses

A study by Gans, Krakauer and Paganelli (1968) dealt with twenty-six species of snakes representing five families. They found that the "rate of water loss was proportional to surface area" and that water loss correlates with the aridity of the selected habitat. No comparative information resulting from the direct separation of the pulmonary and cutaneous avenues of water loss is currently available. Also, no direct comparisons of this separation in sympatric species are available. These comparisons are the basis for this study.

Go to article

First Prev