Dive into oceans, lakes and rivers for a look at underwater war zones, then get a front-row seat at some brutal skirmishes above the waves that determine who wins and who dies.

Animals that live in the rainforest canopy, and how they use the terrain to their advantage when facing an opponent.

The challenges that animals face when trying to survive in some of the driest, fieriest places on the planet, battling exhaustion and dehydration.

How different animals cope with their surroundings, beginning with the icy heat of aggression in some of the coldest habitats on Earth, as life-threatening environmental conditions bring out predators' competitive sides.