Footage of wildlife inhabiting underwater kelp forests, including thousands of giant cuttlefish spawning along a restricted area of rocky reef off the south coast of Australia. Males outnumber females 11 to one, which leads to fierce competition. Larger males use brute force to drive off competition, while their smaller rivals use deception by mimicking the appearance of females. The programme also features tiger sharks hunting for green turtles in fields of seagrass and spider crabs trying to avoid predators while they shed their shells.
The penultimate instalment investigates the primates, whose defining characteristics are forward-facing eyes for judging distance, and gripping hands with which to grasp branches, manipulate food and groom one another. The programme begins in Madagascar, home to the lemurs, of which there are some 20 different types. Two examples are the sifaka, which is a specialised jumper, and the indri, which has a well-developed voice. Away from Madagascar, the only lemur relatives to have survived are nocturnal, such as the bushbaby, the potto and the loris. The others were supplanted by the monkeys and a primitive species that still exists is the smallest, the marmoset. However, Attenborough selects the squirrel monkey as being typical of the group. Howler monkeys demonstrate why they are so named their chorus is said to the loudest of any mammal and their prehensile tails illustrate their agility.
Lions, hyenas, cheetahs, and the highly intelligent African painted dog all have different, but brutally efficient, hunting instincts. Meet these intimidating rulers of the African plains and learn the secrets of their secure reign at the top of the natural food chain.
After the murder of one of its own, the Makulu Pack of wild dogs looks to a new leader for salvation; the Western Pride is exiled to the fringes of the kingdom as it fights to protect its cubs; the marauding hyena clan commits the cruelest of acts.