Horses have an extraordinary fossil record in North America, with specimens from the early Eocene (about 55 Ma) to just the last 10,000 years. The primary dietary strategy in horses changed from browsing –- like that of a giraffe –-to grazing –- like that of modern horses, as seen in the evolution of the higher-crowned teeth. The evolution of tooth structure strongly correlates to variations in the ecosystem due to a changing climate.
To support the understanding of NGSS HS-LS4 Biological Evolution: Unity and Diversity, session participants will engage in the analysis of hypsodonty -- the height of the tooth relative to its overall size -- of fossil replicas to track the evolution of dietary strategy in this lineage to construct an explanation based on evidence to support the claim that changes in environmental conditions may result in the emergence of new species over time. Additionally, participants will communicate their newly gained knowledge in analyzing how horse evolution is depicted in museum displays and design an accurate phylogenetic representation.
The National Center for Science Education supports science teachers through free professional development and curriculum to recognize and address science misconceptions using the three dimensions of the NGSS.
Natural selection acts on genetic variation within populations as individuals who are adapted to survive in the environment reproduce and pass on their genes. Attendees will have the opportunity to work hands-on with a variety of 3D-printed horse teeth dating back to the Eocene to understand how a changing climate played a role in the dietary evolution of horses.
Lin Andrews (National Center for Science Education: Oakland, CA), DeeDee Wright (Colorado State University: Fort Collins, CO), Cari Herndon (National Center for Science Education: No City, No State), Blake Touchet (National Center for Science Education: Oakland, CA)