The first dangerous step into a hazardous world. From egg laying to live-bearing mammals have adopted an extraordinary variety of techniques to give birth, but the release of an egg to the safe delivery of an infant is merely one step in the great journey through life.
For some baby animals, the care of diligent parents smooths the way to adulthood. Whereas others are abandoned before their childhood is over. But whether cared for or not, the main trial remains the same; staying alive during this difficult period.
Finding enough to eat is a problem which faces every animal on the planet and since animals - unlike plants - cannot manufacture their own food, they have to eat other organisms which, by and large, don't welcome the experience.
Whole communities of different kinds of animals have been committed by evolution to live together. We show how some of these animal partnerships are ancient and intricate, whilst others are just being formed and that the delicate balance of benefit and exploitation is ever-changing.
Fighting is most usually an expression of competition - for food, for land or for a mate. But all fights do not have to be expressed with physical violence. Some are also ritualised encounters in which conflict is waged by signals and in which the only damage done is psychological.
Many animals find it advantageous, essential even, to live in social groups where recognising friends and respecting the power of rivals is vital. However there are problems: inevitable squabbles over food, disputes over nesting places and arguments over mates.
In the animal kingdom all sorts of methods are employed to attract the best mate from singing, to fantastical displays of plumage, to stylish dance routines, and more violent strategies like the clashing of horns and the assaults on a rival's property.