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The need for changing how science is taught and the expansion of undergraduate research experiences is essential to foster critical thinking in the Natural Sciences. Most faculty research programs only involve a small number of upper-level undergraduate students each semester. The course-based undergraduate research experience (CURE) model enables more students to take ownership over an independent project and experience authentic research. Further, by creating projects that fit into a curriculum's learning goals and student-oriented outcomes, departments help strengthen critical thinking skills in the classroom. Here, we report on the incorporation of a synthetic biology CURE into a mid-level cellular biology course and two advanced level genetics/molecular biology courses. Synthetic biology involves systematic engineering of novel organisms, such as bacteria and plants, to work as functional devices to solve problems in medicine, agriculture, and manufacturing. The value of synthetic biology and its ultimate utility as a teaching tool relies on reusable, standard genetic parts that can be interchanged using common genetic engineering principles. This Synthetic biology CURE effectively achieves five essential goals: (1) a sense of project ownership; (2) self-efficacy: mastery of a manageable number of techniques; (3) increased tolerance for obstacles through challenging research; (4) increased communication skills; and (5) a sense of belonging in a larger scientific community. Based upon our student assessment data, we demonstrate that this course-based synthetic biology laboratory engages students directly in an authentic research experience and models important elements of collaboration, discovery, iteration, and critical thinking.

Asian-origin avian influenza (AI) viruses are spread in part by migratory birds. In Alaska, diverse avian hosts from Asia and the Americas overlap in a region of intercontinental avifaunal mixing. [...]

The effects of seasonal migration on evolutionary change within lineages is poorly understood, in terms of both differentiation (cladogenesis) and specialization (anagenesis). Regarding differentiation, two contradictory hypotheses exist: Seasonal migration counters differentiation; or it can stimulate differentiation by exposing lineages to new environments. Regarding specialization, the morphological consequences of a migratory life history have not been well explored. We examined these issues by reconstructing morphological and molecular phylogenies of the genus Catharus (Turdidae), a group of forest-dwelling, New World thrushes traditionally considered to include a small 'species flock' of Nearctic-Neotropic migrants. DNA sequence data (2,920-3,027 base pairs) do not support traditional taxonomy, and morphological characters conflicted with these data. Results suggest that long-distance seasonal migration arose independently four times in Catharus sensu lato (including Hylocichla mustelina). Correlated morphological evolution occurred among several characters in these lineages, and these shared traits may stem from ecological conditions in Nearctic forests. Key words: Catharus, convergent evolution, ecological adaptation, molecular systematics, Nearctic-Neotropic migration, parallel evolution, species flocks, thrushes. Los efectos de la migracion estacional sobre el cambio evolutivo de los linajes son poco conocidos en terminos tanto de la diferenciacion (cladogenesis) como de la especializacion (anagenesis). Con respecto a la diferenciacion, existen dos hipotesis contradictorias: que la migracion estacional imposibilita la diferenciacion, o que esta puede estimular la diferenciacion al exponer a los linajes a ambientes nuevos. Con respecto a la especializacion, las consecuencias morfologicas de la historia de vida migratoria no han sido bien exploradas. Examinamos estos aspectos reconstruyendo filogenias morfologicas y moleculares del genero Catharus (Turdidae), un grupo de zorzales del nuevo mundo que tradicionalmente se ha considerado que contiene una pequefia 'bandada de especies' de migrantes neartico-neotropicales. Los datos de secuencias de ADN (2,920-3,027 pares de bases) no apoyan la taxonomia tradicional, y los caracteres morfologicos se encuentran en conflicto con estos datos. Los resultados sugieren que la migracion estacional que involucra grandes distancias surgio independientemente cuatro veces en Catharus sensu lato (incluyendo a Hylocichla mustelina). En estos linajes, sucedio evolucion correlacionada entre varios caracteres morfologicos. Estos rasgos compartidos podrian aparecer como consecuencia de las condiciones ecologicas de los bosques del Neartico.

The article presents a paper which discussed geographic variation in Alaskan Song Sparrows or Melospiza melodia. The researchers examined genetic and morphological characteristics of the Song Sparrows of northwestern North America. They stressed the importance of using multiple lines of evidence, genetic and morphological when evaluating subspecific status. A figure that shows map of Song Sparrow subspecies and collection locations used in genetic data analyses is presented. A pronounced east-to-west increase in individual body mass among subspecies was also observed.