A multi-scale investigation of movement patterns among black-tailed prairie dog colonies

Doctor of PhilosophyDepartment of BiologyJack F. Cully, Jr.Dispersal remains one of the most important, yet least understood, life history traits. As the vehicle of gene flow among populations, dispersal can both relieve inbreeding depression and prevent local adaptation. Regionally, dispersal can stabilize or destabilize metapopulations, given its critical roles in disease transmission among populations as well as recolonization following local extinction events. Furthermore, in light of climate change and increasing habitat loss and fragmentation, the ability to navigate through unfamiliar, unsuitable habitat between populations is essential to the long-term survival of a species across its range. In my dissertation, I present a multi-scale investigation of factors affecting gene flow and disease transmission among populations of a keystone species and an agricultural pest of the North American prairie: the black-tailed prairie dog (Cynomys ludovicianus). Black-tailed prairie dogs are social, ground-dwelling squirrels that live in spatially isolated populations called colonies. First, we conducted a landscape genetic analysis of black-tailed prairie dogs throughout a large portion of their current range. Our estimates of gene flow indicate that the genetic neighborhood size of both male and female prairie dogs reaches 40-60 km within short-grass prairie, whereas colonies within mixed-grass prairie are more isolated. At a broad scale, we observed isolation-by-distance among colonies and great influence of grassland productivity on genetic connectivity; however, neither distance nor landscape characteristics greatly explained observed genetic differentiation among colonies separated by < 50 km. Last, we investigated whether landscape features could predict disease transmission patterns of sylvatic plague among colonies in short-grass prairie and found evidence that pastures act as corridors for plague transmission. Our results indicate that black-tailed prairie dogs are more resilient to habitat loss and fragmentation than other obligate grassland species and likely capable of transmitting sylvatic plague over long distances. Taken together, these studies illustrate how a multi-scale approach can reveal complexities of dispersal dynamics that would otherwise remain undetected

Complementary network-based approaches for exploring genetic structure and functional connectivity in two vulnerable, endemic ground squirrels

The persistence of small populations is influenced by genetic structure and functional connectivity. We used two network-based approaches to understand the persistence of the northern Idaho ground squirrel (Urocitellus brunneus) and the southern Idaho ground squirrel (U. endemicus), two congeners of conservation concern. These graph theoretic approaches are conventionally applied to social or transportation networks, but here are used to study population persistence and connectivity. Population graph analyses revealed that local extinction rapidly reduced connectivity for the southern species, while connectivity for the northern species could be maintained following local extinction. Results from gravity models complemented those of population graph analyses, and indicated that potential vegetation productivity and topography drove connectivity in the northern species. For the southern species, development (roads) and small-scale topography reduced connectivity, while greater potential vegetation productivity increased connectivity. Taken together, the results of the two network-based methods (population graph analyses and gravity models) suggest the need for increased conservation action for the southern species, and that management efforts have been effective at maintaining habitat quality throughout the current range of the northern species. To prevent further declines, we encourage the continuation of management efforts for the northern species, whereas conservation of the southern species requires active management and additional measures to curtail habitat fragmentation. Our combination of population graph analyses and gravity models can inform conservation strategies of other species exhibiting patchy distributions

Biomedical colonialism or local autonomy?: local healers in the fight against tuberculosis

Analiza el papel de los agentes médicos autóctonos y sus conocimientos en las campañas antituberculosas contemporáneas en el África subsahariana. Sitúa la medicina contemporánea, llevada a cabo en África en la herencia cultural de la medicina colonial, para comprender el marco histórico en el que se desarrollaron, a partir de los años setenta del siglo XX, las estrategias de la Organización Mundial de la Salud de promoción y desarrollo de las medicinas 'tradicionales'. En los proyectos sanitarios analizados, se evalúan las prácticas médicas locales y se entrenan a los agentes autóctonos para integrarlos en actividades estrictamente biomédicas: identificación de síntomas, remisión a hospitales o supervisión de tratamientos farmacológicos.The article explores the role played by indigenous medical agents, and their knowledge, within contemporary tuberculosis campaigns in sub-Saharan Africa. To understand the historical framework within which the World Health Organization devised its strategies to promote and develop traditional medicine as of the 1970s, the article contextualizes contemporary medicine as a cultural legacy of colonial medicine. Under the public healthcare projects analyzed in the article, local medical practices were assessed and indigenous agents trained so they could take part in strictly biomedical activities, like symptom identification, referrals to hospitals, or supervision of drug treatments.Trabajo realizado para la obtención del Diploma de Estudios Avanzados (DEA) en el programa de doctorado Salud: Antropología e Historia, bajo la dirección de la profesora Rosa María Medina Doménech

Knowing is half the battle: Assessments of both student perception and performance are necessary to successfully evaluate curricular transformation.

Student-centered pedagogies increase learning and retention. Quantifying change in both student learning gains and student perception of their experience allows faculty to evaluate curricular transformation more fully. Student buy-in, particularly how much students value and enjoy the active learning process, has been positively associated with engagement in active learning and increased learning gains. We hypothesize that as the frequency of students who have successfully completed the course increases in the student population, current students may be more likely to buy-in to the curriculum because this common experience could create a sense of community. We measured learning gains and attitudes during the transformation of an introductory biology course at a small, liberal arts college using our novel curriculum, Integrating Biology and Inquiry Skills (IBIS). Students perceived substantial learning gains in response to this curriculum, and concept assessments confirmed these gains. Over time, buy-in increased with each successive cohort, as demonstrated by the results of multiple assessment instruments, and students increasingly attributed specific components of the curriculum to their learning. These findings support our hypothesis and should encourage the adoption of curricular transformation using IBIS or other student-centered approaches