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During the late Miocene and early Pliocene (latest Hemphillian, Hh4 interval, 5.7 to 4.75 Ma) a distinctive suite of four species of extinct horses (Family Equidae) were widespread in North America. This includes Nannippus aztecus , Neohipparion eurystyle , Astrohippus stocki , and Dinohippus mexicanus. In Florida, two additional equid species, Pseudhipparion simpsoni and Cormohipparion emsliei , are also typically found at Hh4 localities. Here we compare horses from four Hh4 Florida fossil sites, including three from the Bone Valley mines and a fourth from the recently discovered Montbrook site. Two of these sites have all six expected species, one has five species, and one has only four species present. To explain these differences, we used species counts from research databases and rarefaction simulation to clarify the relative abundances, species richness, and occurrences of these horses from these four sites. The Palmetto Mine (Agrico) site, with five equid species, appears to lack the sixth species owing to ecological reasons. This is different from Montbrook, the site with only four of the six species. Results indicate that Montbrook is likely lacking two missing equid species for a couple of reasons: sampling bias and biological/ecological causes. Our results demonstrate that sampling biases can account for observed equid species richness when the overall abundance of certain equid species is low. Nevertheless, other factors, including ecology and with sufficient resolution, perhaps also time, may also explain the distribution and occurrences of individual species at these and other fossil sites. In a broader perspective, analyses such as this example provide an opportunity to address a persistent challenge in paleontology, that is, how do we explain absences of extinct taxa from the fossil record? [ABSTRACT FROM AUTHOR]

One major emphasis of reform initiatives in science education is the importance of extended inquiry experiences for students through authentic collaborations with scientists. As such, unique partnerships have started to emerge between science and education in an ongoing effort to capture the interest and imaginations of students as they make sense of the world around them. One such partnership is called the student-teacher-scientist partnership, in which teachers and their students participate in and contribute to the research of scientists. This article explores a partnership between a 10th-grade biology teacher, her students, and practicing scientists who collaborated in the design, implementation and evaluation of a horse evolution unit. The primary goal of the collaborative activity was to involve teachers and students in a process of conceptual change as a means of eliminating common misconceptions implicit in horse evolution displays in museums in various parts of the country. The evidence-based lessons developed enhanced students' understanding of concepts in macroevolution but also connected the science classroom with a community of scientists whose personalization of the horse evolution unit situated biological concepts and the learning experience within the context of real-world issues.

This study stemmed from concerns among researchers that reform efforts grounded in promoting inquiry as the basis for teaching science have not achieved the desired changes in American science classrooms. Many science teachers assume that they are employing inquiry-based strategies when they use cookbook investigations with highly structured step-by-step instructions. Additionally, most science teachers equate hands-on activities with classroom inquiry and, as such, repeatedly use prepackaged, disconnected activities to break the monotony of direct instruction. Despite participation in numerous professional development activities, many science teachers continue to hold misconceptions about inquiry that influence the way they design and enact instruction. To date, there is very limited research exploring the role of inquiry-based professional development in facilitating desired changes in science teachers' conceptions of inquiry. This qualitative study of five high school science teachers explores the ways in which authentic inquiry experiences with a team of scientists in Panama shaped their conceptions and reported enactments of inquiry-based instruction. Our findings suggest that professional development experiences engaging science teachers in authentic research with scientists have the potential to change teachers' naïve conceptions of inquiry, provided that necessary supports are provided for reflection and lesson design.