Ten simple rules for partnering with K-12 teachers to support broader impact goals.

Contributing to broader impacts is an important aspect of scientific research. Engaging practicing K-12 teachers as part of a research project can be an effective approach for addressing broader impacts requirements of grants, while also advancing researcher and teacher professional growth. Our focus is on leveraging teachers' professional expertise to develop science education materials grounded in emerging scientific research. In this paper, we describe ten simple rules for planning, implementing, and evaluating teacher engagement to support the broader impact goals of your research project. These collaborations can lead to the development of instructional materials or activities for students in the classroom or provide science research opportunities for teachers. We share our successes and lessons learned while collaborating with high school biology teachers to create technology-based, instructional materials developed from basic biological research. The rules we describe are applicable across teacher partnerships at any grade level in that they emphasize eliciting and respecting teachers' professionalism and expertise.

The genetic drift inventory: a tool for measuring what advanced undergraduates have mastered about genetic drift.

Understanding genetic drift is crucial for a comprehensive understanding of biology, yet it is difficult to learn because it combines the conceptual challenges of both evolution and randomness. To help assess strategies for teaching genetic drift, we have developed and evaluated the Genetic Drift Inventory (GeDI), a concept inventory that measures upper-division students' understanding of this concept. We used an iterative approach that included extensive interviews and field tests involving 1723 students across five different undergraduate campuses. The GeDI consists of 22 agree-disagree statements that assess four key concepts and six misconceptions. Student scores ranged from 4/22 to 22/22. Statements ranged in mean difficulty from 0.29 to 0.80 and in discrimination from 0.09 to 0.46. The internal consistency, as measured with Cronbach's alpha, ranged from 0.58 to 0.88 across five iterations. Test-retest analysis resulted in a coefficient of stability of 0.82. The true-false format means that the GeDI can test how well students grasp key concepts central to understanding genetic drift, while simultaneously testing for the presence of misconceptions that indicate an incomplete understanding of genetic drift. The insights gained from this testing will, over time, allow us to improve instruction about this key component of evolution.

Drift promotes speciation by sexual selection.

Quantitative genetic models of sexual selection have generally failed to provide a direct connection to speciation and to explore the consequences of finite population size. The connection to speciation has been indirect because the models have treated only the evolution of male and female traits and have stopped short of modeling the evolution of sexual isolation. In this article we extend Lande's (1981) model of sexual selection to quantify predictions about the evolution of sexual isolation and speciation. Our results, based on computer simulations, support and extend Lande's claim that drift along a line of equilibria can rapidly lead to sexual isolation and speciation. Furthermore, we show that rapid speciation can occur by drift in populations of appreciable size (N(e) >or= 1000). These results are in sharp contrast to the opinion of many researchers and textbook writers who have argued that drift does not play an important role in speciation. We argue that drift may be a powerful amplifier of speciation under a wide variety of modeling assumptions, even when selection acts directly on female mating preferences.

Quantitative genetic models of sexual selection.

Modeling of R.A. Fisher's ideas about the evolution of male ornamentation using quantitative genetics began in the 1980s. Following an initial period of enthusiasm, interest in these models began to wane when theoretical studies seemed to show that the rapid evolution of ornaments would not occur if there were costs associated with female mate choice. Recent theoretical work has shown, however, that runaway evolution and other kinds of extensive diversification of ornaments and preferences can occur, even when female choice is costly. These new models highlight crucial parameters that profoundly influence evolutionary trajectories, but these parameters have been neglected in empirical studies. Here, we review quantitative genetic models of sexual selection with the aim of fostering communication and synergism between theoretical and empirical enterprises. We also point out several areas in which additional empirical work could distinguish between alternative models of evolution.