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Full-Text Articles in Life Sciences

Seasonality Of Conceptions Under Varying Conditions In A Rhesus Macaque Breeding Colony, Ryan Disney Patrick Dunk Aug 2013

Seasonality Of Conceptions Under Varying Conditions In A Rhesus Macaque Breeding Colony, Ryan Disney Patrick Dunk

Theses and Dissertations

Rhesus macaques (Macaca mulatta) are well documented as seasonal breeders. Despite this, little is known about what factors influence seasonal reproduction in rhesus. It has been proposed that rhesus are "relaxed income breeders" (Brockman and van Schaik, 2005), which means they respond to changes in photoperiod but endogenous cues can allow deviations from photoperiod-timed seasonality. This study presents the results of a natural experiment on the influence of different housing conditions (featuring different levels of environmental exposure) on the seasonal pattern of reproduction in rhesus. Once the number of attempts was controlled for, rhesus did not exhibit a seasonal distribution ...


Impact Of Self-Fertilization On Fecundity, The Timing Of First Reproduction, And Population Genetic Structure: Is A Mate Worth The Wait?, Serena Caplins Jun 2013

Impact Of Self-Fertilization On Fecundity, The Timing Of First Reproduction, And Population Genetic Structure: Is A Mate Worth The Wait?, Serena Caplins

Theses and Dissertations

Organisms capable of self-fertilization typically exhibit two evolutionary syndromes uniting high inbreeding depression with low levels of selfing, or low inbreeding depression and high levels of selfing. This study tests for inbreeding depression in an apparent self-compatible, hermaphroditic marine nemertean worm, Prosorhochmus americanus. Fecundity and timing to first reproduction were assessed in isolated and paired worms. Isolated worms produced significantly more offspring than paired worms and did not show inbreeding avoidance. The selfing rate of natural populations was evaluated using species-specific microsatellites and is consistent with preferential selfing (mean: 0.801), though some outcrossing appears to take place. Population genetic ...


Effects Of Environmental Variables On The Reproduction Of Quagga Mussels (Dreissena Rostriformis Bugensis) In Lake Mead, Nv/Az, Richard Steven Ianniello May 2013

Effects Of Environmental Variables On The Reproduction Of Quagga Mussels (Dreissena Rostriformis Bugensis) In Lake Mead, Nv/Az, Richard Steven Ianniello

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2007, quagga mussels (Dreissena rostriformis bugensis) were found in Lake Mead and have spread downstream on the Colorado River and to other lakes and reservoirs in the Southwestern United States. The quagga mussel's extremely quick colonization of Lake Mead and annual veliger abundance trends provide evidence that the quagga mussels in the Southwest have different reproductive behavior than in previous habitats. This study is one of the first to specifically examine quagga mussel reproduction in the Southwest and examines how quagga mussel reproduction varies at sites known to have different temperatures and other environmental variables resulting from the ...


Investigation Of Condition Effects On Batch Fecundity Of The Common Snook, Centropomus Undecimalis, In Tampa Bay, Florida, Catherine Michelle Bruger Hayslip Jan 2013

Investigation Of Condition Effects On Batch Fecundity Of The Common Snook, Centropomus Undecimalis, In Tampa Bay, Florida, Catherine Michelle Bruger Hayslip

Graduate Theses and Dissertations

Common snook, Centropomus undecimalis, is a popular game fish species that occurs throughout central and southern Florida, yet many questions remain unanswered regarding their reproductive strategies, including estimates of fecundity with relation to size, age, and condition of the female. These relationships are critical to improving stock assessments and fundamental to estimating spawning potential ratio, the measure by which snook are managed. Spawning snook were collected from a known spawning site, Rattlesnake Key, Tampa Bay, Florida, during three consecutive spawning seasons (2009-2011) and batch fecundity for snook was reported for the first time. Of the 43 females suitable for fecundity ...


A Comprehensive Research Framework For Geographic Parthenogenesis In Whiptail Lizards (Genus Aspidoscelis), Adam Leland Jan 2013

A Comprehensive Research Framework For Geographic Parthenogenesis In Whiptail Lizards (Genus Aspidoscelis), Adam Leland

UNLV Theses, Dissertations, Professional Papers, and Capstones

One of the most compelling topics in biology has been the ubiquity of sexual reproduction in living organisms. Because the ecological and evolutionary advantages of sex are well founded, those organisms that reproduce asexually remain enigmatic. Parthenogenesis, the clonal reproduction of an all-female species without the need for males, is a relatively common form of asexual reproduction in vertebrates, and has been subject of numerous academic investigations. Many parthenogenic organisms also share aspects of their geographic distributions, such as inhabiting higher latitudes, higher altitudes, islands or island-like habitats, xeric environments, and marginal, disturbed or ecotonal habitats relative to their sexual ...


Benzo[A]Pyrene Effects On Fundulus Heteroclitus Reproductive Endpoints, Frank Booc Jan 2013

Benzo[A]Pyrene Effects On Fundulus Heteroclitus Reproductive Endpoints, Frank Booc

Electronic Theses and Dissertations

Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon (PAH) that modulates aromatase enzyme function and, thus, potentially interrupts normal reproductive function. The aim of this study was to use a fish model, Fundulus heteroclitus, to assess whether BaP exposure adversely impacted reproduction. Adult fish were exposed to waterborne BaP concentrations of (0, 1 or 10 μg/L) for 28 days. Males and females were combined for the second half of the exposure (days 14-28) in order to quantitate egg production and fertilization success. Egg fertilization and subsequent hatching success of F1 embryos was significantly decreased by 10 μg/L ...


The Reproductive Ecology Of Plethodontid Salamanders In The South Carolina Inner Coastal Plain, Heather Rena Oswald Jan 2013

The Reproductive Ecology Of Plethodontid Salamanders In The South Carolina Inner Coastal Plain, Heather Rena Oswald

Theses and Dissertations

Nest- site selection is a critical process in the life history of amphibians, directly influencing offspring survival and parental fitness. When and where an amphibian chooses to nest is strongly influenced by a range of environmental cues. We monitored plethodontid salamander breeding behavior in seepage wetlands in the South Carolina inner Coastal Plain. Seepage wetlands are ideal for monitoring semiaquatic salamander breeding, because they provide habitat for both larval and adult salamanders while having relatively predictable, constant water temperatures and presence year round. We observed the breeding phenology of three sympatric salamanders (Eurycea cirrigera, Desmognathus auriculatus, and Pseudotriton ruber) in ...


Influence Of Soil Nutrients On Reproduction And Pathogenicity Of Rotylenchulus Reniformis On Cotton, Herath Mudiyanselage Manjula Thaminda Kularathna Jan 2013

Influence Of Soil Nutrients On Reproduction And Pathogenicity Of Rotylenchulus Reniformis On Cotton, Herath Mudiyanselage Manjula Thaminda Kularathna

LSU Master's Theses

Among the variety of pathogens of cotton (Gossypium hirsutum), nematodes play a major role in reducing yield. Across the U.S. cotton belt, millions of dollars are lost annually due to nematode infestation. In the Mid-South and Southeast United States, root-knot nematode (Meloidogyne incognita) and reniform nematode (Rotylenchulus reniformis) are responsible for the highest percentage of damage. Crop rotation and nematicides are currently the most commonly used management strategies for nematode management. Soil fertility, which has a direct effect on plant growth, is also known to influence disease severity. Therefore, soil fertility would be an additional factor to consider for ...