Finches on the Galapagos Islands have evolved to exploit almost every possible niche. This diagram shows the range of food sources available on the island and the different beak shapes adapted to exploit each of them.

In this Evolution Web feature, test your skills at judging who's who on the tree of life while you learn about the tools and methods of cladistics.

These images from the Smithsonian Institution depict Nancy Knowlton's work with snapping shrimp in Panama. Knowlton found that the closing of the isthmus -- dividing the Pacific Ocean from the Caribbean -- resulted in new species of shrimp.

Students are introduced to the classification of animals and animal interactions. Students also learn why engineers need to know about animals and how they use that knowledge to design technologies that help other animals and/or humans. This lesson is part of a series of six lessons in which students use their growing understanding of various environments and the engineering design process, to design and create their own model biodome ecosystems.

What types of reading skills do students need to be successful? This informative site focuses on students with learning disabilities. Explore!

Learn about the different types of igneous rocks and how they are classified.

This comprehensive study guide covers the main terms and concepts needed for a unit on classifying organisms.

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Here's a great dichotomous key for beginners. Use gremlin-like creatures to learn how to use more taxonomic keys.

Overview of how placental mammals are classified.

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Explore the classification and evolution of mammals.

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Review the structure, function, and diversity of prokaryotic cells.

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This activity is an introduction to the study of birds. Students will gain observation and classification skills.

Get the facts about Bowhead whales. Besides finding detailed physical descriptions of these mammals of the sea, you?ll also learn about some of their unique facts and characteristics. Also included in this Mammal Fact Sheet on Bowhead whales is information on their habitat and habits, range, feeding, and conservation efforts. A list of resources completes the fact sheet.

In this interactive activity from Shedd Aquarium, build a fish and then release it into the reef to search for food and evade predators. Try different combinations and observe how each kind of fish has unique adaptations that help it survive in its habitat.

Get the facts about the Canada Lynx. Besides finding a detailed description of this predatory feline, you?ll also learn about some of its unique facts and characteristics. Also included in this Mammal Fact Sheet on Canada Lynx is information on its habitat and habits, range, feeding, breeding, and conservation efforts. A list of resources completes the fact sheet.

Get the facts about the Canvasback, a wild duck who only lives in North America. Besides finding a detailed physical description of one of the fastest flying ducks, you?ll also learn about some of this bird's unique facts and characteristics. Also included in this Bird Fact Sheet on the Canvasback is information on its habitat and habits, range, feeding, breeding, and conservation efforts. Don?t forget to check out the video and sound clips of the Canvasback at the top of the webpage. A list of resources completes the fact sheet.

Christina wants to classify all kinds of different things. Help her sort things into main groups.

Get the facts about caribou. Besides finding a detailed description of the caribou, you will also learn about some of their unique facts and characteristics. Also included in this Mammal Fact Sheet on caribou is information on their habitat and habits, range, feeding, breeding, and conservation efforts. Check out the video clips of caribou using the link near the top of the webpage. A list of resources completes the fact sheet.

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.

This activity is a classroom lab where students observe and classify chemical and physical changes using the five characteristics of a chemical change, interpret their findings, and use evidence to support their findings.