This video highlights a team of scientists who work on reconstructing the mass extinction that occurred 250 million years ago, the end of the Permian Period. This event wiped out the majority of life on our planet, resetting the evolution of life. Clues suggest that deadly bacteria might have set off a chemical chain reaction that poisoned the Permian seas and atmosphere.

This video features changes in the land, sea, and animals that are being observed by the residents of Sachs Harbour, Northwest Territories, Canada â many of whom hunt, trap, and fishâbecause of their long-standing and intimate connection with their ecosystem. Scientists interview the residents and record their observations in order to deepen our understanding of climate change in the polar region. Background essay and discussion questions are included.

This video discusses two key signs of global change in the Southern Ocean: changes in Antarctic bottom water and ocean acidification.

This video provides background information and teaching tips about the history and relevance of phenology and seasonal observations of plants and animals within the context of rural Wisconsin.

In this video, students learn how scientific surveys of wildlife are performed at a site in Yosemite, California. These surveys, in conjunction with studies from the early 1900s, provide evidence that animal populations in Yosemite have shifted over time in response to rising temperatures.

This video is part two of a seven-part National Academies series, Climate Change: Lines of Evidence. The video outlines, with the use of recent research and historical data, how we know that the Earth is warming.

This video follows biologist Gretchen Hofmann as she studies the effects of ocean acidification on sea urchin larvae.

This video explores the work of environmentalist John Hart, a Professor of Environmental Science at U.C. Berkley. In the Rocky Mountains of Colorado, Dr. Hart has established an experimental laboratory in which he has artificially created and maintained a 3-degree increase in surface temperature of a plot of land, and documented the impact on plant species occupying the plot.

In this video, the mountain pine beetle problem is explained by two scientists. Their research investigates the beetle and how climate change is hastening its spread.

This video features the Prairie Heating and CO2 Enrichment Experiment near Cheyenne WY, where scientists expose mixed-grass prairie to higher temperatures and CO2 concentrations to study impacts on the prairie for late in this century.