: Breathing is essential to life. And lately, the safety of the air we inhale, or the need to pause and take a deep breath, is on our minds a lot. On this week's show, TED speakers explore the power of breath.

In 2002, freediver Tanya Streeter completed a record-breaking dive of 525 feet-in one breath. She reflects on the obstacles she faced, and the experience of pushing her body and lungs to the limit.

Journalist Beth Gardiner and activist Yvette Arellano explain the long-term health effects of air pollution. Yvette lives in a Houston neighborhood near the largest petrochemical complex in the U.S.

Dinosaurs ruled Earth for 180 million years, but to dominate they had to outcompete a slew of other animals. Paleontologist Emma Schachner thinks their lungs could have been the competitive advantage.

Each day, we breathe about 22,000 times--and all that time we smell. Scent historian Caro Verbeek recreates scents of the past. She says, just like music and art, smell is a part of our heritage.

Mindfulness expert and Headspace co-founder Andy Puddicombe guides listeners through a meditative reflection on how breath can bring us closer together.