In this video profile produced for Teachers' Domain, meet conservationist Steve MacLean, an Inupiaq from Barrow, Alaska, who works to preserve the health of the Bering Sea ecosystem.

For more than twenty years, people have been feeding a large group of friendly stingrays at a place in the Cayman Islands. In this video, Jonathan travels to Grand Cayman to meet up with the famous marine artist and researcher Dr. Guy Harvey who is studying the relationship between humans and stingrays. He even shows Jonathan how to hold a stingray safely in his arms. Please see the accompanying study guide for educational objectives and discussion points.

Even when we model the dynamics of the abundances of molecules inside biological systems using calculus, it is important to remember that underlying behavior can be apparently random ("stochastic"). Even a deterministic system containing components moving in periodic ways can, at early times, support dynamics that appear disordered. The behavior of systems containing complicated collections of interacting parts can be difficult to predict with accuracy (chaos). Finally, systems can display stochasticity because the outcomes of measurements on quantum systems are indeterminate in a fundamental way. Random processes are modeled using Markov models.

In this analysis and discussion activity, students learn how the function of cells, organs and organ systems is related to structure (including shape, constituent components, and relationships between components). Students analyze multiple examples of the relationship between structure and function in diverse eukaryotic cells and in the digestive system. In addition, students learn that cells are dynamic structures with constant activity and they learn how body systems interact to accomplish important functions.

This animation adapted from Garland Science Publishing takes a close look at the DNA double helix and its individual components, describing their chemical structures and how they function together to make the DNA molecule unique.

Studying life on the seafloor beneath Antarctica's thick ice is a major challenge for ecologists. Learn about a new device that can reach those icy depths in this video segment adapted from WomenInAntarctica.com.

This reference list has more than 25 books on biodiversity. For each title, the book's author, publisher, and publication date are given. The diverse list includes broad introductions to biodiversity, insightful looks at evolution and extinction, examinations of the partnership between insects and flowers, portraits of vanishing species and explorations of the factors contributing to a global biodiversity crisis.

This video segment from FRONTLINE/NOVA: "Harvest of Fear" explores genetic modification of salmon and possible consequences.

In this lesson designed to enhance literacy skills, students learn about the varied physical and behavioral adaptations that animals rely on to help them survive changing environmental conditions, such as the arrival of winter.

In this activity, learners use a chemical reaction to visualize where moisture forms on the body. Learners use the Minor's iodine-starch test, a diagnostic test that doctors use to detect hyperhidrosis (excessive sweating), to identify where moisture is forming. Learners also use this method to test the effectiveness of different antiperspirants.

Perhaps best known for its role as the antagonist in the film Jaws, the Great White shark is probably the world‰ŰŞs most feared animal, and easily the most fearsome of the sharks. In this video, Jonathan travels to Mexico to meet a Great White up close and personal. Nothing can prepare him for the sheer size and strength of a fully grown Great White shark! He learns how white sharks are being studied and how they react to both people and sea lions. Please see the accompanying study guide for educational objectives and discussion points.

When manatees were first seen by Columbus, he thought they were mermaids..but he had been at sea for a long time! Today these gentle marine mammals are threatened by loss of habitat and collisions with boats. This video segment explores the endangered manatees of Florida and their struggle to survive, as well as some of the people who are working to save them. Please see the accompanying lesson plan for educational objectives, discussion points and classroom activities.

This video segment adapted from NOVA reveals how junk DNA helped solve an evolutionary mystery: Why do certain species of fruit flies have wing spots while others don't?

The peacock provides a classic example of sexual selection, the force behind nature's extravagances. From Evolution: "Why Sex?"

This BioBulletin Web site takes a close look at the medicinal power of plants. The site includes text, videos, photographs, and interviews with key scientists. Age-Old Remedies discusses how nearly 80 percent of the world's population relies on medicines made from natural ingredients. The Power of Traditional Medicine takes an historical look at medicinal herbs and traditional healers. Bio-Prospectors Needed reports on the symposium "The Value of Plants, Animals, and Microbes to Human Health" that was held at the American Museum of Natural History. Tracking Down a Power Plant tells the story of a tree in the Sarawak rain forest that contains a possible cure for AIDS.

This video segment from the Nevada Department of Wildlife looks at tarantulas' survival skills and their habitat.

This winning entry in the museum's Young Naturalist Awards 2001 by Amber, a 17 year old student from Iowa, studies tardigrades in the U.S. and Antarctica. Her essay details her field study in Missouri, which compared the diversity, distribution, and abundance of tardigrades both upwind and downwind from the James River power plant and an account of the 10 days she spent in Greenland with international tardigradologists, during which she found a rare occurrence in tardigrade behavior.

Bonnie Chen builds on students' prior knowledge of mutations to lead her class through a simulation of wading birds feeding.

Marilyn Havlik leads students through a simulation of the Hardy-Weinberg Principle to develop their understanding of population genetics.

In this transcript of an interview filmed for Evolution: "Great Transformations," Ted Daeschler and Neil Shubin describe the discovery and significance of some of their key fossil finds.