Sir David Attenborough chooses his favorite recordings from the natural world --from the song of the largest lemur to the song of the humpback whale to the song of the lyrebird-- that have revolutionized our understanding of song. The science of song had been transformed by Charles Darwin’s theory of sexual selection: singing is dangerous as it reveals the singer’s location to predators, but it also offers the male a huge reward, the chance to attract a female and pass on genes to the next generation. Today, new science in the field of birdsong is transforming those long-held ideas.
Scientists are discovering that, in fact, in the majority of all songbird species, females sing - and it is only now they are being properly heard. Through this revelation and others, we can understand that animal songs are marvellous examples of the spectacular survival strategies that species have developed.

Deep in the jungles of Taiwan lives female giant golden orb-weaver spider -- among the biggest web building spiders on the planet. With a leg-span of almost eight inches and silk like kevlar, she's a fearsome predator. But the orb spiders must find a way to mate with her male counterparts, who are approximately 10 times smaller and 500 times lighter than she is.

In America the summer twilight brings out a magical display of glittering lights. Millions and millions of fireflies, an ethereal sight. But behind this twinkling facade is a fierce female setting a deadly trap. The femme-fatale of fireflies is part seductress, part vampire, as Reese shows us the fireflies' deadly trickery to provide nourishment to their young.

The plains of Africa, home to a powerful predator where females rule: spotted hyena. They have a reputation as dim-witted scavengers. But these fierce queens are the opposite; strong, fearless and highly intelligent. Hyenas are the girl gang of the Savannah. They hunt in packs, get first bite of their prey, and outrank every male in their group, making them some of Africa's most fierce queens.

One extraordinary family of fish has achieved the ultimate form of gender equality. When it comes to breeding, seahorses do it like no other animal on the planet. Their fierce females refuse to be left holding the baby. So it's the males that carry their brood. In this episode we explore the world of mating seahorses which are the only animals in the world that have a major gender role reversal.

There is one miniature fierce queen, hardly bigger than a grain of rice. Enter the fascinating, and sometimes brutal world of honey ants, struggling not just for survival, but power - all in service of their fearless leader, the queen. Her story has it all-- ambition, murder, and a great army of female warriors on the rampage.