1900 Air Pollution

Examine this graph from FRONTLINE/NOVA: "What's Up with the Weather?" Web site to see dramatic increases in three greenhouse gases over the last two hundred years.

Agricultural Runoff and the Gulf of Mexico Dead Zone

This video segment adapted from Big River: A King Corn Companion shows how agricultural chemicals from the Midwest that travel downstream in water runoff create a vast marine "dead zone" in the Gulf of Mexico.

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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Arctic Tundra

This video segment from Wild Europe: "Wild Arctic" explores the struggle for survival in one of Earth's most extreme environments.

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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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Biomes

This interactive resource adapted from NASA describes the different temperature, precipitation, and vegetation patterns in seven biomes: coniferous forest, temperate deciduous forest, desert, grassland, rainforest, shrubland, and tundra.

Bt Corn

This video segment from FRONTLINE/NOVA: "Harvest of Fear" looks at corn that has been genetically modified to resist one insect pest, and the multiple concerns it raises.

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Carnivorous Plants of Texas

In this video adapted from Texas Parks and Wildlife Department, learn about carnivorous plants that act as both producers and consumers in an ecosystem. See sundews and blatterworts capture and digest insects.

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Changing Arctic Landscape

In this video adapted from the Arctic Athabaskan Council, learn how warmer temperatures in the Arctic are transforming the landscape, triggering a host of effects such as permafrost thawing and insect infestations.

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Chris Schneider: Rethinking Conservation

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

Classical vs. Transgenic Breeding

This video segment from FRONTLINE/NOVA: "Harvest of Fear" explains that genetic engineering and classical breeding both alter the genetic makeup of crop plants.

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Compare the Poles

Explore the defining features of the Arctic and the Antarctic in this interactive activity adapted from the Woods Hole Oceanographic Institution.

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.

Contaminants in the Arctic Food Chain

The levels of contaminants found in particular animals vary widely depending on where they fit into the Arctic food chain, as described in this video segment adapted from LOKE Films and the Arctic Monitoring and Assessment Programme.

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Contaminants in the Arctic Human Population

In this video segment adapted from LOKE Films and the Arctic Monitoring and Assessment Programme, learn how human populations in the Arctic are affected by industrial contaminants in the food chain.

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Continental Divide: The Breakup of Pangaea

Examine geological evidence found in fossils, rock deposits, and ancient mountains that supports the theory of continental drift in this interactive activity adapted from the Exploratorium.

Deep Sea Vents and Life's Origins

Deep-sea vents are home to strange, luminescent life forms that thrive through chemosynthesis. This video segment from NOVA: "Volcanoes of the Deep" hypothesizes life's beginnings in this extreme environment.

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Desert Biome

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

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Endocrine Disruptor Hypothesis

Scientists discuss whether or not endocrine disrupting chemicals, which may cause birth defects and other health concerns, should be controlled in the absence of conclusive proof, in this video segment adapted from FRONTLINE: "Fooling with Nature."

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Energy Flow in the Coral Reef Ecosystem

This video segment, adapted from NOVA, describes the energy flow in a coral reef, including its food web.

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