Covers seven characteristics shared by all living organisms.[Free Registration/Login may be required to access all resource tools.]

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Covers how species interact with each other.

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Covers the four unifying principles of biology.

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Covers Darwin's theory of evolution by natural selection.

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Can you identify the purpose of different bird beaks? Read up about the different types of beaks and then you'll apply your knowledge by identifying the purpose of different shaped beaks.

In this Nature video, learn about the extraordinary impact that birds have on the agriculture of a small Indian community.

“Bug Hunt” uses NetLogo software and simulates an insect population that is preyed on by birds. There are six speeds of bugs from slow to fast and the bird tries to catch as many insects as possible in a certain amount of time. Students are able to see the results graphed as the average insect speed over time, the current bug population and the number of insects caught. There are two variations to try for the predator, one where the predator pursues the prey and one where the predator stays still and captures insects that pass nearby. In the first case the “bird” catches the slow insects and the faster ones survive, reproduce and pass genes on. The average speed of bug should increase over time. In the second case the faster bugs come near to the bird more often than the slow ones. The slow ones survive more, reproduce and pass their genes on.

Few people are aware of how crucial the sense of smell is to identifying foods, or the adaptive value of being able to identify a food as being familiar and therefore safe to eat. In this lesson and activity, students conduct an experiment to determine whether or not the sense of smell is important to being able to recognize foods by taste. The teacher leads a discussion that allows students to explore why it might be adaptive for humans and other animals to be able to identify nutritious versus noxious foods. This is followed by a demonstration in which a volunteer tastes and identifies a familiar food, and then attempts to taste and identify a different familiar food while holding his or her nose and closing his or her eyes. Then, the class develops a hypothesis and a means to obtain quantitative results for an experiment to determine whether students can identify foods when the sense of smell has been eliminated.

In this video segment from NatureScene, explore Cartwheel Bay, a wetland in South Carolina, and learn about the variety of carnivorous plants native to this unique landform.

In this video segment adapted from NOVA: Becoming Human, learn how the analysis of rock layers and ocean sediments supports the theory that rapid climate change may have jump-started human evolution two million years ago.

In small groups, students experiment and observe the similarities and differences between human-made objects and objects from nature. They compare the function and structure of hollow bones with drinking straws, bird beaks, tool pliers, bat wings and airplane wings. Observations are recorded in a compare & contrast chart, and then shared in a classroom discussion, along with follow up assessment activities such as journal writing and Venn diagrams.

In this video segment adapted from NOVA, scientists search for carbonized remains of plants preserved in lava flows to find out how long it has taken rain forests on Hawaii to regenerate after a volcanic eruption.

This video segment from NOVA: A Desert Place describes the physical characteristics and organisms that define the desert biome.

This expository article for elementary students describes the dinosaurs that lived in polar regions as well as the adaptations that helped them survive in the dark and cold environment. Modified versions for younger grades are available.

Students learn about the amazing adaptations of the ptarmigan to the alpine tundra. They focus one adaptation, the feathered feet of the ptarmigan, and ask whether the feathers serve to only keep the feet warm or to also provide the bird with floatation capability. They create model ptarmigan feet, with and without feathers, and test the hypothesis on the function of the feathers. Ultimately, students make a claim about whether the feathers provide floatation and support this claim with their testing evidence.

This video segment from the Science and Technology Chat series focuses on dolphin pregnancy, birth, and care of the young, and features Atlantic bottlenose dolphins living in captivity at the Mirage Resort Dolphin Habitat.

Explains how natural selection favors certain traits in a population so that the organism adapts to its environment, and that changes in the genes over time cause evolution.

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Overview of the basic concepts behind evolution, such as gene variation and adaptations.[Free Registration/Login may be required to access all resource tools.]

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Summarizes the key points about adaptations, mutation, evolution, and natural selection. Includes a few questions to check for understanding.

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This pathway explores the importance of biodiversity and human impact on the environment.