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  • The Making of the Fittest: Evolving Switches, Evolving Bodies

    The Making of the Fittest: Evolving Switches, Evolving Bodies

    Short Films

    (15 min 27 sec) After the end of the last ice age 10,000 years ago, populations of marine stickleback fish became stranded in freshwater lakes dotted throughout the Northern Hemisphere in places like Alaska and British Columbia. These fish have adapted to a freshwater environment drastically different than the ocean.

  • The Making of the Fittest: Natural Selection and Adaptation

    The Making of the Fittest: Natural Selection and Adaptation

    Short Films

    (10 min 25 sec) The rock pocket mouse is a living example of Darwin’s process of natural selection. Also available in Spanish.

  • Paintbrush Gene

    Paintbrush Gene

    Animations

    (49 sec) In two related Drosophila species, a so-called paintbrush gene is activated to "paint" the pigment on the body. In one species, an extra switch activates the gene, resulting in spotted wings.

  • Pitx1 Expression

    Pitx1 Expression

    Animations

    (55 sec) In the stickleback fish, pelvic-fin reduction resulted from changes in the regulatory switch elements of the Pitx1 gene. In the marine ancestor, the Pitx1 gene is activated in the pelvic-fin region during development to generate the fin. In the pelvic-reduced stickleback, the regulatory switch that normally turns on the Pitx1 gene is either missing or non-functional.