From PBS - Joy and Mark travel to Africa to explore the unique reproduction challenges of the largest animal on land -- the elephant. Find out how females select the strongest mates, why elephants have the longest pregnancy in the animal kingdom and how they safely deliver a 220-pound baby; witness the remarkable first steps of a newborn calf.

From PBS - Joy and Mark travel to Borneo to explore the reproduction challenges of our close cousin -- the orangutan. The largest tree dwellers on the planet, orangutans mate, give birth and raise their young high in the jungle canopy. At an orangutan sanctuary in the rainforest, Mark and Joy come face-to-face with a super-male and uncover the latest scientific theories about how these kings exert their power over other males and seduce females in their territory. Joy witnesses the sneaky tactics that the females use to take control of mating and Mark finds out how males fight back. The lengthy period dedicated to raising one child is critical to the success of orangutans and all the other great apes -- including us

From PBS - In Australia, Joy and Mark uncover the reproductive secrets of some of the strangest mammals on Earth -- the pouch-wearing marsupials. Thanks to their bizarre way of reproducing, kangaroos thrive in one of the most unpredictable, drought-prone environments on Earth -- the Australian Outback. In Queensland's eucalyptus forests, he sees how tree-living marsupials -- koalas -- have mastered gravity-defying sex. At a kangaroo sanctuary, Joy witnesses a tiny newborn's first steps as it crawls to the pouch, and in Adelaide, she learns how endangered rock wallabies are being saved using foster mothers. During a kangaroo dissection, she learns what makes marsupial reproductive anatomy unique.

From PBS - Joy and Mark investigate the reproductive secrets of marine mammals to learn how animals that breathe air manage to mate, give birth and raise their young underwater. Joy travels to New Zealand to uncover the mating strategy of dusky dolphins. While she reveals the adaptations marine mammals have evolved to mate in the ocean, Mark travels to Mexico to find out how whales find mates in the ocean vastness. Witness a dolphin birth, explore the difficulties of breastfeeding underwater and learn how dolphin and whale young avoid predatory killer whales.