Are We Alone?

This video segment adapted from NOVA features a variety of scientific perspectives on the age old question, "Are we alone in the universe?" Animations make vivid the improbability that we could intercept a radio wave signaling extra terrestrial intelligence.

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Becoming a Fossil

This video segment describes how the Australopithecus afarensis skeleton known as Lucy could have been fossilized. Footage courtesy of NOVA: "In Search of Human Origins."

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Caves: Extreme Conditions for Life

This video segment adapted from NOVA raises the provocative idea that if life can exist in the most extreme environments on Earth — such as in dark, toxic caves — then perhaps living things can also survive in harsh environments on other planets.

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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.

Dating Lava Flows on Mauna Loa Volcano, Hawaiʻi

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 Hawaiʻi to regenerate after a volcanic eruption.

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Decision-Maker Bees and the Human Brain

Learn about the similarity between the pattern of communication within a bee colony and neural networks in the human brain, in this video adapted from NOVA scienceNOW.

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Evolutionary Roots of Language

This video excerpt from NOVA scienceNOW looks at how language and tool-making may have coevolved.

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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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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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Finding Lucy

This Evolution video segment depicts the landmark hominid fossil finds by Don Johanson and his team in Ethiopia.

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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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Fossil Evidence of Bipedalism

This video segment adapted from NOVA shows how scientists use the fossil record to trace when early human ancestors and related species began walking on two legs instead of four, and to determine whether they were more apelike or human in appearance.

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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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Homo Sapiens Versus Neanderthals

This video segment, adapted from NOVA, explores reasons why Homo sapiens had an advantage over Neanderthals in the pursuit of territory and natural resources.

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Ingredients for Life: Water

This video segment adapted from NOVA goes on a whimsical journey in search of life forms thriving in extreme conditions on Earth and in outer space. Animations show ice on Jupiter's moon, Europa, and signs that water once existed on Mars.

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Insight and Imagination

Get an overview of how insight and imagination distinguish humans from others in this segment from The Human Spark.

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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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Laetoli Footprints

This Evolution video segment describes how the famous track fossils known as the Laetoli footprints might have been formed and what they can reveal about the creatures who left them.

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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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Profile: Ethiopian Anthropologist

In this video adapted from NOVA scienceNOW, meet Ethiopian anthropologist Zeresenay Alemseged and find out why his work has made him a national hero and the leader of a new generation of African-born anthropologists.

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Radiometric Dating

In this video segment from A Science Odyssey: "Origins," scientists explain how Earth's age was determined by radiometric dating.

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Root Systems of Trees at the Congaree Swamp

Learn about root systems of trees in the Congaree Swamp National Park in this video segment from NatureScene.

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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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