This video segment follows neurophysiologist Allen Counter as he studies an epidemic of hearing loss in Moriussaq, Greenland, one of the quietest places on Earth. Footage from NOVA: "Mystery of the Senses: Hearing."

Coral reefs are often portrayed as brightly lit, bustling underwater marvels full of colorful creatures. This video segment, adapted from NOVA, paints a different picture as it explores the nocturnal behavior of organisms in the reef.

In this lesson designed to enhance literacy skills, students examine the nutritional content of different foods and learn about the health benefits and risks associated with the food choices they make.

This video segment from Nature profiles a small business in which homing pigeons play a central role.

This video segment explores the role of touch in the development of young animals, including humans. Footage from NOVA: "Mystery of the Senses: Touch."

In this video adapted from Texas Parks and Wildlife Department, learn about the prairie dog, the importance of its role in its ecosystem, and how it is affected by an ever-growing human population.

In this video segment from NatureScene, observe dragonflies and mayflies near Cedar Creek at Congaree Swamp National Park.

This video segment from Nature features ravens, the most intelligent birds in the crow family.

This video segment from NatureScene describes the characteristics of redwood trees at Redwood National Park.

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

In this video segment from NatureScene, discover some reptiles in the swamp forest ecosystem at Congaree Swamp National Park.

In this video segment from NOVA scienceNOW, meet researchers who are studying obesity and trying to understand the role that hormones and genetics can play in regulating appetite.

Learn how ravens benefit from sharing information and working together in this video segment from Nature.

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

This video from Thinkport introduces the seahorse, an unusual, endangered fish that has puzzled scientists who are attempting to save it.

This video segment adapted from Northwest Indian College reveals how Native American life and knowledge is connected to natural cycles.

In this lesson designed to enhance literacy skills, students learn about the varied physical and behavioral adaptations that animals rely on to help them survive changing environmental conditions, such as the arrival of winter.

Why do teenagers act the way they do? This video segment from FRONTLINE: Inside the Teenage Brain explores the work scientists are doing to explain some of the mysteries of teenage behavior.

In this video segment adapted from the International Institute for Sustainable Development, Inuit observers describe how their traditional understanding of weather patterns is being challenged by unpredictable weather behaviors.