|Next of Kin|
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Land of Giants
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A family group of Australopithecus afarensis is down on its luck; yet another female died from malaria, leaving behind an orphan son. The males of the group, Grey and Hercules, are beginning to challenge each other for leadership, and the females are supporting Hercules rather than Grey, particularly a female aptly nicknamed Babble, who hates him and after the matriarch's death, has taken over. A bigger, more numerous group of Australopithecus attacks, driving the focus group from their old home. Because of this, they start to migrate through the highlands of Ethiopia, searching for a new one.
During their travels they run into a male Deinotherium in musth: his body was full of hormones and very aggressive: he chased the australopithecines up a tree and almost trampled one of their youngsters before he left. Fortunately, none of the australopithecines were seriously hurt.
Shortly after the Deinotherium encounter the australopithecines discover a new place to live: at first it seems to be uninhabited by other large mammals, except for Ancylotherium, and not even australopithecines are scared of them. However, this is also a home of Dinofelis, a sabre-toothed cat that specializes in hunting prey such as Australopithecus. Dinofelis begins to hunt australopithecines and successfuly too. The family group is shrinking further.
However, the situation begins to improve: a new female arrives... Causing new tension between the males of the family group, Grey and Hercules. Eventually, discovering the usage of a stick as a weapon, Hercules defeats Grey and becomes the new leader of the family group.
Eventually the Dinofelis returns and attacks australopithecines once more. Blue, the Australopithecus youngster orphaned at the beginning of the episode, is almost captured and killed by the cat when the rest of the family group rallies together and chases Dinofelis away with sticks and stones. As the carnivore is driven away and australopithecines begin to groom each other, the narrator points out that they have a long journey to travel yet, but it's a start.
This episode focuses on a group of Australopithecus (identified as Australopithecus afarensis in The Complete Guide To Prehistoric Life). They are depicted as apes, but with the ability to move upright, just as modern humans do. This allowed australopithecines to travel long distances on open ground, something that other apes just couldn't do, leaving their hands free to use in other ways. (It also forced them to mate facing each other, something that other mammals don't do, as a rule.) This allowed australopithecines to start using simple tools, which helped them to become smarter and to adapt to a changing environment, becoming ancestors of such species as Homo Habilis and Homo Rudolfensis from which modern humans would eventually evolve.
The other mammals depicted in this episode are a combination of computer graphics and live footage: Next of Kin depicts both prehistoric animals (Deinotherium, Ancylotherium, Dinofelis) and modern species - rhinoceros, warthog , zebra, vulture . This helps to picture a world in transition: the old, Paleogene world of megafauna began to vanish (as symbolized by Ancylotherium: its knuckle-walking cousins from Land of Giants belonged in the megafauna world of the Miocene, while Ancylotherium was something of a living fossil instead), and the new Neogene world of smaller, smarter animals (including the australopithecines) began to appear
Deinotherium and other giant mammals had had their day, but in the Pliocene it was drawing to a close. This was in part due to evolution of grass - although it had appeared relatively early during the Cenozoic, it began to dominate the landscape during the Neogene, causing new species of herbivores to appear (like the modern antelopes). This caused a domino effect among the animals that fed on plants or on herbivores
Although Dinofelis was a sabre-toothed cat, it wasn't related to Smilodon (featured in the next episode), but was a different mammal altogether, specializing on hunting primates. It possessed sabre-like teeth (but short ones) and the fossil discoveries show that it was a professional hunter of Australopithecus and similar mammals, as it was depicted in the episode. This was down to the fact it wasn't as fast as a modern cheetah is, and couldn't attack fast herbivores.