• Zinhle "Zinny" Thabethe
Zinhle "Zinny" Thabethe has a voice that moves audiences to tears, a voice that brings enormous hope to those living with HIV/AIDS. She is one of the lead vocalists in the Sinikithemba Choir, an internationally acclaimed HIV-positive vocal ensemble. But she is also a frontline activist in South Africa, providing medicine and counseling to those afflicted with HIV/AIDS. She joins Boyd in the studio to talk about how the most important medicine is hope.

• Bruce Barcott
Sharon Matola was a mushroom expert, an Air Force survival specialist and an Iowa housewife. Now she’s the director of the Belize Zoo. In his new book, The Last Flight of the Scarlet Macaw, award-winning author Bruce Barcott chronicles Matola’s inspiring crusade to save the beautiful bird. Barcott joins Boyd to talk about the book and the remarkable woman at the center of the story.

• David Budzinski
Have you seen the amazing YouTube video called Battle at Kruger? Over thirty million people have. Boyd talks to David Budzinski, the tourist who caught the amazing tournament of animal survival at a South African watering hole while on safari. The video is featured in a new National Geographic Television special, Caught on Safari: Battle at Kruger, airing this Sunday.

• Seth Bauer
One man’s trash is another man’s compost. Seth Bauer, Editorial Director of the Green Guide, helps us grow green in this week’s Green Guide segment.

• Adam Pack
As the director of the Dolphin Institute in Hawaii, Adam Pack spends plenty of time swimming with dolphins. But he has also spent plenty of time in the water with humpback whales. He talks with Boyd about attaching Crittercams to whales and what he is learning from the resulting video footage.

• Sarah McNair-Landry
Young explorer Sarah McNair-Landry is currently trekking through the Arctic on an expedition with Will Steger. McNair-Landry joins Boyd via satellite phone from Ellesmere Island to talk about keeping warm at night and scaring away the many polar bears they’ve encountered on the trip so far.

• Mary Olive Smith
Every year over nine thousand Ethiopian women suffer from a devastating childbirth injury that often leads to them being rejected by their husbands and ostracized by their communities. But the injury is easily corrected. Boyd talks to filmmaker Mary Olive Smith who, in a new Nova documentary, A Walk to Beautiful, tells the stories of five Ethiopian women who embark on a journey to reclaim their lost dignity.

• Story-Walk Across Arctic Ice
Boyd Matson tells of a walk across Arctic ice that leaves him with one foot in today and another in tomorrow!