Adaptive Radiation: Darwin's Finches

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.

The Advantage of Sex

Why did sex evolve? The likely answers, in this essay for the Evolution Web site by science journalist Matt Ridley, may surprise you.

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.

Ancient Farmers of the Amazon

This video segment from Evolution: "Evolutionary Arms Race" tells the story of the leafcutter ant and the fungus it farms -- an example of mutually beneficial symbiosis.

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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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Biological Invaders

This video segment from Evolution: "Extinction!" shows the impact of invasive species on native ecosystems.

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Chasing Beetles, Finding Darwin

In this video from KQED's QUEST, find out how Darwin's ideas remain as central to scientific exploration as when they were first published 150 years ago.

Chris Schneider: Rethinking Conservation

In this interview filmed for Evolution: "Darwin's Dangerous Idea," biologist Chris Schneider discusses the relationship between conservation and speciation.

Co-Evolution

Students explore different types of symbiotic relationships that exist between species.

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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Complex Relations

In this text excerpted from chapter 3, "Struggle for Existence," of Charles Darwin's On the Origin of Species, Darwin draws on firsthand and historical information for his observations about evolution.

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.

Coral Reef Connections

Dive in and explore what makes this beautiful world so fragile. In this Evolution Web feature, discover how coevolution has shaped the ecological relationships among reef creatures.

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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E. O. Wilson: Ants and Ecosystems

This segment is from an interview with ant specialist and biologist E.O. Wilson, filmed for Evolution: "Evolutionary Arms Race."

Evolution of Camouflage

This video segment from Evolution: "Darwin's Dangerous Idea" illustrates the remarkable camouflage of a praying mantis against its leafy backdrop.

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Evolution of the Eye

Zoologist Dan-Erik Nilsson demonstrates how the complex human eye could have evolved from simple light-sensitive cells. From Evolution: "Darwin's Dangerous Idea."

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Evolution on Double Time

This excerpt from Evolution: The Triumph of an Idea by Carl Zimmer describes how gene duplication may have been the key to the rapid evolution of the early stages of life on Earth.

Evolving Ideas: How Does Evolution Really Work?

The process of evolution through natural selection is the focus of this video segment from Evolution, which presents a field study of hummingbird speciation in Ecuador.

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Evolving Ideas: How Do We Know Evolution Happens?

This video from Evolution focuses on one of the several lines of evidence for evolution -- fossils, highlighting the evolution of whales from land-dwelling mammals to the aquatic creatures we know today.

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Evolving Ideas: Why Does Evolution Matter Now?

In this video from Evolution, an exploration of multi-drug resistant tuberculosis in the Russian prison system highlights one reason it is important to understand evolution.

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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.

Fish with Fingers

In this video segment from Evolution: "Great Transformations," paleontologist Jenny Clack explains that vertebrates evolved fingers before they invaded land.

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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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Genetic Drift and the Founder Effect

This image of polydactyly illustrates one symptom of Ellis-van Creveld syndrome, which is commonly found in the Amish. Ellis-van Creveld is one example of the founder effect and genetic drift.

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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Genetic Tool Kit

The shared set of genes for body segments, possessed by all animals, are discussed in this video segment from Evolution: "Great Transformations."

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Genetic Variation

This video segment from NOVA: "Cracking the Code of Life" explores the genetic similarities and differences among organisms.

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HIV Immunity

Although repeatedly exposed to HIV, Steve Crohn's blood cells were never infected. Dr. David Ho investigates in this video segment from NOVA: "Surviving AIDS."

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How Evolution Works

Students learn about natural selection by discussing the evolution of the eye, genetic variation, adaptation, sexual selection, and the Galapagos finches.

How New Species Evolve

Students learn about both allopatric and sympatric speciation.

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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Hummingbird Species in the Transitional Zones

This video segment from Evolution: "Darwin's Dangerous Idea" shows biologists Chris Schneider and Tom Smith studying hummingbirds and other animals in Ecuador. Their research is investigating the processes by which new species are formed.

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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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Isolating Mechanisms: Lacewing Songs

Hear the different songs of three lacewing flies, which serve as reproductive isolating mechanisms between species and determine mate choice. Lacewing audio song from Charles Henry.

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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The Mating Game

This interactive feature from the Evolution Web site takes a lighthearted but informative look at some of the strategies various organisms use to reproduce.

Microbe Clock

In this Evolution Web feature, learn how mutation and fast reproductive rates can allow deadly microbes to outpace medical breakthroughs.

Mike Novacek: Fossils in the Gobi

Biologist Mike Novacek discusses his discovery of mammal fossils in the Gobi Desert and what we can learn from them. From Evolution: "Extinction!"

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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A Mutation Story

This video segment describes the role of the sickle cell gene in natural selection. Footage courtesy of the PBS series Secret of Life: "Accidents of Creation."

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An Origin of Species

In this Evolution Web feature, witness for yourself how a new species can evolve as you observe natural selection and adaptive radiation in action.

Permian-Triassic Extinction

In this video segment from Evolution: "Extinction!", geologist Peter Ward discusses evidence for a Permian-Triassic mass extinction.

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Pink Dolphins of the Amazon

This video resource from Jean-Michel Cousteau: Ocean Adventures explores the unique adaptations developed by the pink river dolphin in order to survive in the freshwater rivers of the Amazon.

The Red Queen

An example of the Red Queen hypothesis, the sexual population of Mexican Poeciliid fish are able to keep up with a changing environment, while the asexual populations are not as successful. From Evolution: "Why Sex?"

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