Allopatric Speciation

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.

Animal Body Plans: Homeobox Genes

The homeobox genes that define the basic body plan of mice and fruit flies are illustrated in this graphic from The Human Evolution Coloring Book by Adrienne Zihlman. The accompanying article describes how these genes act as "molecular architects" in all animal species.

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The Common Genetic Code

Paul Nurse describes his research that showed that humans share some genes with organisms as different from us as simple brewer's yeast. Footage from Secret of Life: "Immortal Thread."

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Convergence: Marsupials and Placentals

This graphic illustrates some of the marsupial mammals in Australia and placental mammals in North America. Even though they are not closely related, these mammals look alike because they have adapted to similar ecological roles. From The Human Evolution Coloring Book by by Adrienne Zihlman.

Engineering Biofuels

In this video segment adapted from KQED's QUEST, find out how synthetic biologists use the techniques of metabolic engineering and directed evolution to make more effective biofuels.

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Finch Beak Data Sheet

This graphic from Ecology and Evolution of Darwin's Finches by Peter Grant presents data from the Galapagos Islands, showing that a severe drought put selective pressure on the population of Darwin's finches and resulted in a change in the average beak size in the next generation.

Floral Arrangements

Explore a few of the ways plants pollinate each other in this video segment from Sexual Encounters of a Floral Kind.

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Frozen Frogs

This video segment adapted from NOVA scienceNOW shows how the common wood frog freezes solid every winter, an adaptation that allows the organism to survive the cold winter.

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Genetically Engineering the Avian Flu

In this video segment adapted from NOVA scienceNOW, learn about a radical biotechnology experiment aimed at figuring out how to stop the avian flu virus.

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Geneticist Pardis Sabeti

In this video profile adapted from NOVA scienceNOW, learn about geneticist and rock musician Pardis Sabeti, whose innovative insights into natural selection demonstrated how beneficial mutations spread quickly through a population.

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Human Chromosome 2

In this video segment adapted from NOVA: "Judgment Day: Intelligent Design on Trial," learn how modern genetics and molecular biology offer compelling support for evolution. The video features an interview with biologist Ken Miller.

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Investigating Neanderthals

This video excerpt from NOVA scienceNOW looks at how head shapes of Neanderthals and modern humans differ.

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Killer Microbe

Learn how biotechnology is used to analyze the evolution of a formerly harmless bacterium into a highly drug-resistant and lethal pathogen in this video segment adapted from NOVA scienceNOW.

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Leafy Spurge

This video segment from Evolution: "Extinction!" shows how biological control is successfully combating North Dakota's infestation of leafy spurge, a non-native plant.

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Masters of Disguise

In the face of danger, what's a spineless animal to do? This video segment introduces the concept of camouflage -- how animals achieve it and how this form of disguise benefits both predators and prey. Footage from NOVA: "Animal Impostors."

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Mimicry: The Orchid and the Bee

In this photograph from Oxford Scientific Films, a horned bee attempts to mate with an Ophrys orchid, which has evolved to resemble a female bee.

Molecular Clocks: Proteins That Evolve at Different Rates

From The Human Evolution Coloring Book by Adrienne Zihlman, four different proteins from humans and horses are compared in this graphic and article, and the reasons each protein evolves at its own characteristic rate are discussed. Each protein is useful for measuring evolutionary change over a different time scale.

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The Reproductive Role of Flowers

In this video segment adapted from NOVA, learn about the critical role of flowers in seed plant reproductive biology.

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Saving the World’s Potatoes

This audio segment from PRI's The World Science Podcast explores the extraordinary variety of potatoes native to the Andes in South America, and the current mission to protect this biodiversity.

Shape of Trees: The Frustration Principle

This series of images shows the work of biologist Karl Niklas on the adaptations and evolution of plants. From The Evolutionary Biology of Plants.

Switching Genes On and Off

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?

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To Make a Spear

About 100,000 years ago, humans began to develop the spear, representing the beginnings of projective technology and organized hunting.

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Transitional Tetrapod Fossil

In this video segment from NOVA: "Judgment Day: Intelligent Design on Trial," learn about the discovery of a well-preserved transitional fossil and how such transitional fossils support the theory of evolution.

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Unique Species of Kentucky's Green River

This KET video from Kentucky's Last Great Places shows how the Green River has remained unusually clean and why it is home to several endangered aquatic species.

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Whales in the Making

This graphic from Evolution, traces the evolution of whales from land-dwelling mammals to the aquatic creatures we know today.

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