Unusual Fish that 'Walks' Holds Clues to Animal Evolution An unusual species of fish that can walk and breathe air shows that these animals may be more capable of adapting to life on land than previously thought, researchers say. The new findings may help explain how the ancient fish ancestors of humans colonized the land, the researchers said. The evolution of the ancient fish that switched from living in water to living on land about 400 million years ago is one of the most pivotal moments in the history of the animal kingdom.
Is Evolution Predictable? If one could rewind the history of life, would the same species appear with the same sets of traits? Many biologists have argued that evolution depends on too many chance events to be repeatable. But a new study investigating evolution in three groups of microscopic worms, including the strain that survived the 2003 Columbia space shuttle crash, indicates otherwise. When raised in a lab under crowded conditions, all three underwent the same shift in their development by losing basically the same gene. The work suggests that, to some degree, evolution is predictable. More than 50 years ago, researchers studying basic cell biology began raising a tiny soil worm, the nematode Caenorhabditis elegans.
Materials Search Return to MERLOT II Home Page Search all MERLOT Click here to go to your profile Classroom Resources In this three-part lesson, students learn about natural selection, the mechanism that drives evolution. They begin by discussing the evolution of the eye and how even a complex organ can evolve through natural selection. Then they divide into groups to learn about genetic variation, adaptation, and sexual selection and report their findings back to the class. Finally, students analyze data to determine how the beak length of Galápagos finches evolves according to environmental factors. 1. Who Evolved on First? Bud Abbott and Lou Costello While I was writing this post, I heard that Bill Nye and Ken Ham are planning to have a debate about evolution and creation. While it could be an interesting conversation, I suspect that it will suffer from the same communication problems that afflict most of these debates. Have you ever heard the brilliant comedy routine, “Who’s on first?” by Bud Abbott and Lou Costello?
<em>En Garde!</em> Animal Structures and What They Mean Teaching Notes Case teaching notes are password-protected and access to them is limited to paid subscribed instructors. To become a paid subscriber, begin the process by registering here. Teaching notes are intended to help teachers select and adopt a case. They typically include a summary of the case, teaching objectives, information about the intended audience, details about how the case may be taught, and a list of references and resources. Download Teaching Notes Simple worms are closet brainiacs - life - 14 March 2012 DON'T be offended, but you have the brain of a worm. Clusters of cells that are instrumental in building complex brains have been found in a simple worm that barely has a brain at all. The discovery suggests that, around 600 million years ago, primitive worms had the machinery to develop complex brains. They may even have had complex brains themselves - which were later lost.
Resources for Teaching Biology The Sourcebook for Teaching Science This book provides science educators with a comprehensive selection of innovative tools, activities, and high-quality instructional resources for enlivening lessons across the science disciplines. It features over 300 classroom-ready activities ranging from word-based problem-solving exercises to hands-on laboratory experiments and includes examples drawn from biology, physics, chemistry, and the geosciences, all linked to National Science Education Standards. The chapter titles and related resources may be found in the column on the right.