Some animals appear to have taken nature's gifts and stretched them to extreme limits. In this remarkable natural history documentary, David Attenborough looks at the chameleon's tongue and the giraffe's neck. One animal ended up with a super-stretched neck, the other a stretchy tongue. In both cases nature has found a way to turn the ordinary into the extraordinary.

Nature can be so baffling we sometimes don't believe what we see. David Attenborough discovers the curiosities connected to the platypus and the tadpole in this illuminating natural history documentary. The attributes of these animals, one laying eggs the other transforming into a frog, are so extraordinary, they have led to accusations of forgery and have ultimately made us rethink evolution.

Aging and eternal youth seem to fascinate us. In this enlightening natural history documentary, David Attenborough encounters two examples where curious bodies and extreme lifestyles may unlock the secrets of the ageing process and longevity. For the elephant and the mole rat, the wrinkly skin of these animals has nothing to do with age but helps them to survive in their environments.

Both the narwhal and the snail have developed a twist. The narwhal has its ferocious tusk while the humble snail carries its chic mobile home on its back. In this curious natural history documentary, David Attenborough questions why spirals are so widespread in nature. He gleans some answers by looking at a variety of animals that feature a spiral in their physical make up.

Animals that are beautifully patterned or brilliantly colored have attracted the attention of collectors for centuries. David Attenborough examines a zebra's stripes and the wings of a butterfly in this intriguing natural history documentary. Using modern tools and techniques, he attempts to unlock the secrets of animal patterns that have bedazzled and baffled science for a long time.

Recently it was discovered that female Komodo dragons can reproduce without ever having contact with a male. In this illuminating natural history documentary, David Attenborough investigates the science behind this. He finds that in our own back gardens female aphids can clone themselves and produce thousands of copies. How and why do these two very different animals reproduce by virgin birth?