Our second project focuses on sperm morphology: our fish are the only vertebrates on the planet that naturally lack flagella on their sperm! We have identified a candidate causal mutation for this phenotype, and are exploring the consequences of this adaptation using multiple approaches. Our first project is to determine the genetic basis of sex, which appears to be under the control of a master sex determining gene that has convergently evolved in numerous teleost lineages. Most recently, we've embarked on several projects to investigate the idiosyncratic reproductive systems of African weakly electric fish. Our work takes place in the field, the laboratory and in silico. I leverage these convergent evolutionary outcomes to tackle three broad questions on the cutting edge of evolutionary biology: (1) How do changes in the genome lead to the evolution of novel phenotypes? (2) What are the evolutionary forces that influence this process? and (3) What are the consequences of this interaction for the evolution of biodiversity? Our work isįundamentally integrative and spans biological levels of analysis and disciplines, including ecology and evolution, genomics and bioinformatics, physiology, developmental biology, and animal behavior. The electric fish system is therefore highly amenable to understanding the link between genotype and phenotype because it provides replicated natural experiments in which evolution has produced similar phenotypic outcomes both within and between lineages.
Two parallel electric fish lineages have undergone rapid speciation as a consequence of electric organ evolution and exhibit convergent evolution at every biological level: from molecules to ecology.
In each case, electric organs evolved to produce electric fields for the purposes of communication and navigation, and occasionally for predation and defense. For this reason, my research program focuses on electric fish, vertebrate species that have independently evolved electric organs six times. While the evolution of novel traits has led to a rich tapestry of species, the single origin of these traits presents a statistical dilemma for evolutionary biologists: they are single replicate ‘experiments’ that lack power to resolve how and why novel traits evolve. Many charismatic, uniquely vertebrate traits such as fins, limbs, feathers, teeth evolved once long ago, and enabled profound diversification. Vertebrates have evolved a multitude of adaptive traits to exploit resources in the air, on the land, and in the water. Trinity College, Hartford, CT (Biology and Human Rights) Postdoctoral Research, Boston University Research Interest The study builds on the available knowledge by considering the avenues by which social networking use poses a threat to mental health and well-being given the pervasive nature of social networking in the modern world.Ph.D. In contrast to the hypothesized findings, social networking use was found to be relatively calming. There was a main effect for stress pairwise comparisons showed a significant reduction in negative affect for individuals not partaking in the stress manipulation. Significant reductions in negative affect over time were found, regardless of condition. The covariate empathic concern was nonsignificant. No significant interaction effects were found for stress or social comparison. No significant differences were found for change in positive or negative affect between conditions. A mixed factorial ANOVA assessed changes in negative affect, and a mixed factorial ANCOVA assessed changes in positive affect across conditions.
They rated their subjective experiences before and after viewing preconstructed social networking profiles and those assigned to the Stress conditions underwent a stress manipulation (Trier Social Stress Test) prior to viewing the social networking profiles. Participants were randomly assigned to one of four conditions: (1) Downward Comparison – No Stress (2) Upward Comparison – No Stress (3) Downward Comparison – Stress (4) Upward Comparison – Stress. The study investigated the impact of stress and social comparison via social networking platforms on affect. Social Comparison Theory has drawn considerable attention in this area however, findings have been mixed concerning the situational factors influencing the relationship between social comparison, social networking, and affect. Research concerning the influence of social networking on our mood and well-being has been steadily growing over the past decade.
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