Mammals dominate the planet. They do it through having warm blood and by the care they lavish on their young. Filming in the bitter Antarctic winter reveal how a mother Weddell seal wears her teeth down keeping open a hole in the ice so she can catch fish for her pup. A powered hot air balloon captures stunning images of millions of migrating bats as they converge on fruiting trees in Zambia.
- Length: 59:00
- Aired: 3/28/2010