forms most beautiful” can emerge. Teachers are encouraged to use and
adapt these activities and the associated discussion slides – which
include human examples of polydactyly (Gilbert & Barresi, 2018)
and eye color (White & Rabago-Smith, 2011) to demonstrate the roles
of enhancers in causing phenotypic changes.
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PBS (2011). What Darwin never knew. NOVA. https://www.pbs.org/wgbh/
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Shubin, N. (2009). The zoo of you. NOVA. https://www.pbs.org/wgbh/nova/
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toolkit of wing pattern genes. Nature Ecology & Evolution, 1, article 0052.
VanCott, R. (2009). Guess the embryo. NOVA. https://www.pbs.org/wgbh/
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and human eye color. Journal of Human Genetics, 56, 5–7.
MICHAEL I. DORRELL is a Professor of Biology at Point Loma Nazarene
University, San Diego, CA 92106. He is also a Senior Staff Scientist
Consultant at the Lowy Medical Research Institute, La Jolla, CA 92037.