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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Identifying mating systems of imperiled marine turtles nesting in southern Florida through exclusion analysis to estimate the breeding sex ratio

Unknown Date (has links)
The reproductive behavior of migratory organisms is difficult to characterize as the mating behavior can be difficult to observe. For some species, one sex can be readily observable, but the other may remain hidden, confounding attempts to assess population demographics. For such species, it can be difficult to determine the sex ratio of the population. Without accurate accounts of the numbers of males and females, conservation methods may be insufficient and their performance unclear. Alternative methods of measuring sex ratios therefore must be used to estimate the number of individuals and assess breeding behavior. Here I identified breeding sex ratios (BSR) measured using paternity analysis of offspring through exclusion analysis to quantify the numbers of males contributing. Here I discuss the mating behavior of three species of marine turtle that nest in southern Florida: the loggerhead (Caretta caretta), the leatherback (Dermochelys coriacea), and the green sea turtle (Chelonia mydas) at three beaches (Boca Raton, Juno Beach, and Sanibel Island) from 2013-2017; over 400 nesting females were identified and genotyped and almost 7,000 hatchlings were collected and genotyped. Females from all three species successfully mated with more than one male in all years analyzed demonstrating multiple paternity of clutches. For loggerheads, many male genotypes were identified, suggesting that females likely mate en route to their nesting grounds, inducing a male-biased BSR. Examination of females that were sampled more than once per season (repeats), evidence of sperm storage was found for all nests and some turtles might mate in between nesting events. Leatherback females displayed a higher rate of multiple paternity than was previously published for other Caribbean nesting sites; I hypothesize that this result may be due to a mainland nesting beach effect. The leatherback BSR over all years was approximately 1:1, and one male was identified fathering than two different females’ nests (polygyny). For green turtles, multiple paternity was found and there was evidence of polygyny. Across all three species, evidence for indirect benefits of mating multiply (hatching success or larger hatchlings) was weak or not supported. Together, the four studies contribute to the overall body of reproductive behavior studies. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
2

The diversity of firefly and preliminary study of the mating behavior of Luciola anceyi Olivier in Guanziling, Tainan

Jheng, You-Cheng 09 August 2012 (has links)
The objective of this study was to investigate the diversity of fireflies and the mating behavior of Luciola anceyi in Guanziling, Tainan. The field study was carried out from September 2010 to April 2012. The nocturnal survey of number of individuals and species of firefly was within one hour after sunset weekly in two transects, Jiulongshan 1 (JS1) and Shiya valley (SV). The diurnal firefly survey was from 2011 March to May once for every two weeks in these two transects. In addition, vegetation species and layers was recorded in these two transects during winter and spring. The sex ratio, population size and mating behavior of L. anceyi were studied in three transects (Jiulongshan 2, Jiulongshan 3 and Dadongshan) with mark-recapture and digital video camera. Total 6 genus and 14 species of firefly were found in JS1 and SV, Guanziling from September 2010 to December 2011. The maximum number of firefly species reached its peak of 8 in May and June in Guanziling, but no adult firefly was found in January, February and September. Four species of fireflies were found active during daytime, including Drilaster olivieri, Pyrocoelia formosana, Vesta scutellonigra and L. anceyi . The Shannon-Wiener¡¦s diversity index and evenness of nocturnal fireflies were both highest in summer, significantly higher than those from other seasons (Tukey's HSD, P¡Õ0.05). During spring and summer, 12 species of firefly species were recorded but only 4 species was recorded during autumn and winter. In 2011, Luciola cerata was the most dominant species in firefly community in Guanziling, accounted for 68.21%. The second comeon one was Luciola praeusta (9.48 %), followed by Luciola anceyi (6.42%), Curtos mundulus (5.92%), Diaphanes citrinus (4.47%), and Pyrocoelia praetexta (3.29%). The highest average density within one hour after sunset of L. cerata was from April to May (22.77/ 100 m2 and 15.54/ 100 m2 in JS1 and 6.07/ 100 m2 and 5.91/ 100 m2 in SV). The number of L. cerata was positively correlated with temperature in SV (P¡Õ0.05), but the number of L. anceyi was negatively correlated with relative humidity in SV (P¡Õ0.001). The number of L. praeusta was positively correlated with temperature of these two transects (P¡Õ0.05), and C. mundulus was positively correlated with temperature and relative humidity (P¡Õ0.05) in SV. But the number of D. citrinus and P. praetexta were neither correlated with temperature nor relative humidity from these two transects (P¡Ö0.05). Vegetation stratification in SV was more complex than in JS1, and firefly communities were influenced by plant stratification. The relative frequency of plant layer was the highest in two layers of shrub and herb (winter¡G31.82%¡Fspring¡G33.64%) and three layers of tree, shrub and herb (winter¡G30.91%¡Fspring¡G34.55%) among seven layers of plants in SV. On the other hand, The relative frequency was the highest in the single herb layer in JS1 (winter¡G47.50%¡Fspring¡G48.75 %), and lacking herb layer, two layers of tree and shrub and three layers of tree, shrub and herb. L. cerata prefers to appear in the grasslands of JS1, and D. citrinus and P. praetexta prefer to appear in the habitat with complex vegetation in SV. The courtship and copulation behavior of L. anceyi were recorded during daytime as well as nighttime. The number of adult male L. anceyi captured during daytime flying was significantly higher than adult female captured (P¡Õ0.05). During nighttime, the recapture rate of marked adult males of L. anceyi was twice that of adult females (15.94 % versus 8.55 %). It indicates that the adult L. anceyi appears to be active in the daytime and nighttime in the same area. The mating behavior of L. anceyi occurrs both day and night, therefore, male L. anceyi most likely uses chemical signals to find mates during day time. The mating pattern of L. anceyi is not corresponded with any sexual communication systems known for fireflies. Therefore it can be regarded as a new type of activity and sexual communication systems for fireflies. Although Guanziling area is influenced by long-term cultivation and over development, the quantity and species number of fireflies are plentiful and fireflies occur in all four seasons. Therefore Guanziling has the potential for developing ecotourism and firefly-watch. However, firefly-watch can also increase the damage to the environment. How to appropriately develop ecotourism without destroying the habitat may become the challenge and test for the goal of sustainable management. Finally, the results of this study can provide useful information for habitat conservation and management of fireflies in Guanziling.
3

The relationship between cheliped color and body size in female Callinectes sapidus and its role in reproductive behavior

Williams, Kirsten Laurene 15 November 2004 (has links)
Many species use color during courtship displays, with the more colorful individuals often selected as potential mates. Female blue crabs, Callinectes sapidus, display prominent red markings on their chelipeds, which is absent in males. I tested the hypothesis that females use this sexual dimorphism as an effective signal to potential mates. Body size was positively correlated with size of the colorful pattern on the crusher dactyl. Digital imaging techniques were used to examine and quantify a pattern of coloration in the female blue crab. Morphometric measurements were made using digital images of the carapace and chelae of crabs collected along the Gulf of Mexico coast in Galveston, Texas. Color complexity was examined on digital images of the chelae using Adobe? Photoshop? and Image J. Specific wavelengths were selected and their presence within the attribute quantified and evaluated. To determine whether male blue crabs prefer more colorful females, males were given a choice between females of different female coloration. Males displayed more often and directed more courtship displays towards the more colorful females. I hypothesize that male blue crabs use cheliped coloration as a visual cue for mate selection.
4

The Role of Context in Investment into Reproductive Tissue and Implications for Mating

Carsten Conner, Laura Diane January 2007 (has links)
Reproductive traits are often thought of as fixed, genetically determined properties. However, such traits are often dynamic, exhibiting different expression patterns depending on context. Both internal state and external environment can have a strong effect on how traits are expressed. Variation in these factors across the lifetime of an individual should select for flexibility in trait expression, rather than fixation.My dissertation work examines how mating behavior and testes size respond to several previously unexplored contextual factors, using Rhagoletis juglandis, the walnut fly, as a model system. For mating behavior, I predicted that differences in female reproductive state (egg load) and experience with host resource would impact mating decisions. For testes size, I predicted that social environment (sex ratio) and changes in resource environment would determine testes size.Behavioral observations of flies showed that a large egg load increased the likelihood of copulation, while prior experience with host fruit decreased copulation time. These results are the first to distinguish effects of experience on physiological state from other effects of experience in the context of mating behavior.Manipulation of the sex ratio revealed that males develop larger testes when reared in an environment with many potential competitors. This is the first study to show that that allocation to a male reproductive organ can change depending on the sex ratio. My studies showed that resource environment is also important in determining testes investment patterns. When adult males are deprived of protein, they develop smaller testes. A stable isotope analysis of testes further confirms that resource environment is important for testes development. Males rely more on nitrogen derived at the larval stage than at the adult stage, but adult carbon sources are a large component of testes mass.In sum, this dissertation demonstrates the importance of context in the expression of reproductive traits. Recent research has shown that such traits can respond more dynamically to context than previously thought, but this area of research is young. My results help provide a greater understanding of the processes shaping the evolution of reproductive traits.
5

First Male Sperm Precedence in Multiply-Mated Females of the Cooperative Spider Anelosimus Studiosus (Araneae, Theridiidae)

Jones, Thomas, Parker, Patricia G. 01 January 2008 (has links)
Patterns of sperm usage in multiply-mated females have profound fitness consequences for males, and create strong selective pressure on male behavior. In the cooperative theridiid spider Anelosimus studiosus Hentz 1850 adult males are tolerated in females' webs, and females have been observed to mate multiply with different males. In this experiment, virgin females were mated with two different males on consecutive days under controlled conditions to determine paternity patterns and behavioral responses of males to non-virgin females. The paternity of broods was analyzed using randomly amplified polymorphic DNA (RAPDs). Fifteen broods were analyzed and complete first male sperm precedence was found. Mating behavior differed between first and second males with the first males attempting fewer intromissions, but having a longer total time of intromission. This suggests that the second males are either prevented from normal copulation, or are reacting to the different condition of the females. The sperm precedence pattern is discussed with respect to its ramifications for male behavior, juvenile inclusive fitness, and the evolution of cooperative behavior.
6

The causes and consequences of variation in the cloacal microbiome of tree swallows (Tachycineta bicolor)

Hernandez, Jessica 31 August 2021 (has links)
Animals are ecological landscapes that host communities of microbes often referred to as microbiomes. These microbes can be transferred between individuals when they come into contact, such as during mating. Microbes that reside in or on any aspect of a host that becomes exposed to the reproductive tract or gametes comprise the reproductive microbiome. These microbes within the reproductive microbiome are important to overall host biology because they can influence host reproductive function, and thus play a role in shaping host ecology, evolution, and fitness. Though previous work has revealed much about the impact of beneficial and pathogenic microbes within the reproductive tract, much is left to be learned from describing the dynamic nature of the reproductive microbiome, and ultimately, how it affects host fitness. For my dissertation, I asked questions regarding how and why reproductive microbiome diversity varies among individuals. For instance, does reproductive microbiome diversity vary with respect to the number of mates or mating activity? Does reproductive microbiome diversity vary with host age or breeding stage? Are there fitness consequences associated with differences in reproductive microbiome diversity? To explore these questions, I studied tree swallows (Tachycineta bicolor), a socially monogamous bird in which both females and males engage in extra-pair mating activity. I focused on the cloacal microbiome as it is the site of contact during mating, and thus where microbes can be sexually transferred between individuals. I found that social partners did not have more similar cloacal microbiome diversity compared to other individuals in the same population, and that cloacal microbiome diversity was similar between sexes (Chapter II). By combining an observational approach with a hormone implant manipulation, I found that neither the number of sires per brood nor the increased mating activity of females significantly influenced cloacal microbiome richness or community structure. However, female age and breeding stage did significantly correlate with cloacal microbiome richness and community structure (Chapter III). Based on these findings, I hypothesized that the effect of mating activity on variation in the cloacal microbiome may only be detectable over a female's lifetime, and not within a single breeding season. In addition, I found evidence for a relationship between lay date and cloacal microbiome structure, after controlling for age. And I found that older females lay earlier in the season compared to younger, first-time breeding females (Chapter IV). These results provide support for a relationship between lay date and the cloacal microbiome and highlight the importance of age to this relationship. Lastly, I discussed future steps that can be taken to extend the framework established by my dissertation research, and thereby gain further insight into the factors shaping the reproductive microbiome (Chapter V). / Doctor of Philosophy / Animals host communities of microbes often referred to as microbiomes, and these microbes can be transferred between individuals when they come into contact, such as during mating. Microbes that reside in or on any part of a host that becomes exposed to the reproductive tract make up the reproductive microbiome. These microbes within the reproductive microbiome are important to an animal's biology because they can influence reproductive function, such as fertilization and pregnancy success. Though previous work has revealed much about the impact of beneficial and pathogenic microbes within the reproductive tract, much is left to be learned from describing the dynamic nature of the reproductive microbiome as a whole and how it affects an animal's reproductive success. For my dissertation, I sought to understand how and why reproductive microbiome diversity varies among individuals, especially in relation to mating. To explore these questions, I studied tree swallows (Tachycineta bicolor), a species of bird in which females and males will pair up to breed and rear young, yet both may mate with individuals other than their partner. I focused on the microbiome within the cloaca of birds as it is where contact is made during mating, and thus where microbes can be sexually transferred between individuals. I found that social partners did not have more similar cloacal microbiome diversity compared to other individuals in the same population, and that cloacal microbiome diversity was similar between females and males (Chapter II). Since tree swallows frequently mate with multiple partners and it is possible for bacteria to be acquired though each mating attempt, I proposed that it is important to consider the number of mates per individual when assessing the diversity of the cloacal microbiome. I then performed observational and experimental studies where I assessed the number of mates per female and manipulated female sexual activity with hormone implants. I found that neither the number of sires per brood nor the increased mating activity of females influenced cloacal microbiome diversity, however, female age and breeding stage were significantly associated with cloacal microbiome diversity (Chapter III). Based on these findings, I hypothesized that the effect of mating activity on variation in the cloacal microbiome may only be detectable over a female's lifetime, and not within a single breeding season. In addition, I found evidence for a relationship between lay date and cloacal microbiome structure, after controlling for age. And I found that older females lay earlier in the season compared to younger, first-time breeding females (Chapter IV). Taken together, these results provide support for a relationship between lay date and the cloacal microbiome and highlight the importance of age to this relationship. Lastly, I discussed future steps that can be taken to extend the framework established by my dissertation research and gain further insight into factors shaping the reproductive microbiome (Chapter V).
7

Falling in Love as a Heuristic for Mate Choice Decisions

Burke, Monica D 19 March 2007 (has links)
Selecting a mate is one of the most important and complex decisions that we make in our lives. Research on human decision making has found that we often use simple rules of thumb or heuristics to facilitate complex decision-making tasks (e.g., Gigerenzer & Todd, 1999; Kahneman & Tversky, 1972, 1973; Tversky & Kahneman, 1974, 1983). Recent research has focused on the use of affect or emotion as heuristics that have a strong influence on a variety of decision making contexts (Damasio, 1994; Finucane, Peters, & Slovic, 2003; Loewenstein, Weber, Hsee, & Welch, 2001; Mellers, 2000). The emotion we most closely associate with the context of choosing a mate is the emotion of love. The focus of this paper is on how love may serve as a heuristic to facilitate and guide our mate choice decisions. In order for falling in love to serve as an effective heuristic for making mate choice decisions, it should be triggered by characteristics that are adaptive from a mate satisfaction and evolutionary perspective. In Study 1, an attempt was made to ascertain the range of characteristics that people feel are most important to the experience of falling in love by asking participants to generate important partner characteristics for falling in love, casual sex, and marriage. In Study 2, the relative importance of the top characteristics was further refined using a Q-sort methodology. It was found that characteristics important to falling in love corresponded closely to those important for marriage. However, attractiveness and characteristics indicating that a person is enjoyable to be around, warm towards others, and an effective and honest communicator were seen as more important to falling in love than marriage. In Study 3, the role of falling in love as a simplifying heuristic for long-term mate choice decisions was assessed using a policy capturing approach. Results indicated that falling in love functions as a decision criterion only when partner characteristics are at their best levels. The implications of these findings for the role of falling in love as a heuristic for long-term mate choice decisions are discussed.
8

Functional Dissection of the Sensory Rays in Caenorhabditis elegans Male Mating Behavior

Koo, Pamela Kristine 2010 December 1900 (has links)
The nematode Caenorhabditis elegans, with its sequenced genome, compact nervous system and stereotyped behaviors is an ideal model organism in which to study the integration of sensory input with motor output. Male mating behavior is among the most complex of these behaviors and males utilize a number of sensory organs in its execution. Among these are the rays, which are nine pairs of sensory organs that are arranged laterally along the male tail. Each ray is composed of two ultra-structurally distinct neuron types, an A type and a B type, surrounded by a glia-like structural cell. Though compositionally identical, each pair of rays maintains a unique, genetically-hardwired identity based on wiring, morphology, and neurotransmitter fate. Three techniques were used to investigate the role of the rays in male mating behavior. First, cauterization of the tips of the rays removed their sensory endings, leading to ray neuron death. Second, a heterologous light-activated cation channel was utilized to activate specific ray neuron types. Finally, ray neuron types were genetically targeted to undergo apoptosis by expression of heterologous caspases. The results show that the rays play important roles in multiple steps of male mating behavior, including contact response, scanning, and turning. The rays as a whole mediate posture change and backing during contact response. The ability to respond to hermaphrodite contact is shared among the rays, as is initiation of backward locomotion, though all rays are required for efficient, prolonged backward scanning. Both A and B neuron types appear capable of initiating contact response. Direct activation of B neurons through ChR2 causes a contact response-like ventral tail flexure, and elimination of both A and B neurons reduces contact response. A neurons additionally have a unique role in turning.
9

Seeing Beyond Words : Animals teach us about our natural ability to lead

Wagenknecht, Ronja January 2018 (has links)
Nonverbal communication in leadership is a phenomenon which is interesting to get a greater understanding of. Animals only communicate nonverbally and have strong leadership behaviours. Therefore, this study aim is to find out in what way nonverbal communication in leaders is still connected to animal roots and what the implications for modern life are. This study tries to give an overview of the phenomenon with a theoretical approach. Different point of views of nonverbal communication and animal behaviour in leaders have been discussed. A theoretical approach was suitable because of the abundance of literature in the main fields of focus. Connecting the different studies with each other gave valuable insights into the phenomenon. Power, status, submission, territory, space, and mating behaviours are the most used categories associated with leadership behaviours in animal species. Human leadership behaviour consists of the same categories but furthermore, emotional intelligence is an integral part as well. Different postures, gestures, facial expressions as well as distances to each other gave a comprehensive overview of how leaders are naturally behaving. Deciphering the complex nonverbal communication and looking at them with aspects of communication in animals helped with showing the roots and the natural ability to lead. Further research, however, should be conducted to see how nonverbal communication influences complex group dynamics and the effect thereof. Implications for the natural instincts to lead are helpful with how leaders can further their communication skills and become more conscious of their nonverbal communication.
10

Ovarian function and reproductive behaviors across the female orangutan life cycle

Durgavich, Lara 24 February 2016 (has links)
Due to their phylogenetic position as an outgroup to humans and the other African apes, empirical data from orangutans are an especially valuable comparative tool with which questions about the evolution of human life history and reproductive characteristics can be addressed. Yet few such data are available. In this dissertation, I use endocrinological and behavioral data from 7 female and 3 male orangutans housed at the Woodland Park Zoo in Washington and the Great Ape Trust in Iowa to characterize the ovarian function and reproductive behaviors of captive female orangutans at different points in the life cycle. Ovarian hormone measurements were achieved through the use of non-invasive urine sampling, and assays reveal both intra- and inter-individual variation in hormone production. Results indicate that (1) adolescent females in captivity do not experience a marked period of subfecund estrogen and progesterone levels in association with reproductive maturation, (2) individual females exhibit both "high quality" and "low quality" cycles, including instances of anovulation, in the absence of fluctuating dietary and environmental conditions, (3) mating behaviors vary between individuals and with cycle phase, but are not strongly influenced by absolute ovarian hormone concentrations, and (4) reproductive senescence does not significantly impact the ovarian function and mating behaviors of aging female orangutans. These results demonstrate that many aspects of human reproductive biology and behavior, such as an extended period of mating receptivity, are evolutionarily conserved. They suggest, however, that the decline in human ovarian function in mid-life may be derived and of possible adaptive significance. The potential significance of differences between captive and wild ape populations, and the character, history, and familial relationships of the particular individuals discussed are considered in the interpretation of all data.

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