![](https://image.tmdb.org/t/p/original/bsabO3soam3onaOXth0QZ8Ye16E.jpg)
![](https://image.tmdb.org/t/p/w342/hw0RsW5V6oywYWspMeLTlftKbFW.jpg)
Survival of the Fittest
The human race is here today because of its ability to adapt. Our ancestors, the earliest mammals, survived low oxygen levels. Later primates developed sharp eyesight and hands that could clasp for nocturnal life in trees.
Stars:
![](https://image.tmdb.org/t/p/w300/bsabO3soam3onaOXth0QZ8Ye16E.jpg)
![](https://image.tmdb.org/t/p/w300/elMGphkKUdT5rP56fZRtdKMi0UF.jpg)
Other episodes for this season
![The Violent Past](https://image.tmdb.org/t/p/w300/bsabO3soam3onaOXth0QZ8Ye16E.jpg)
![Snowball Earth](https://image.tmdb.org/t/p/w300/bsabO3soam3onaOXth0QZ8Ye16E.jpg)
![New Frontiers](https://image.tmdb.org/t/p/w300/bsabO3soam3onaOXth0QZ8Ye16E.jpg)
![Extinction and Rebirth](https://image.tmdb.org/t/p/w300/bsabO3soam3onaOXth0QZ8Ye16E.jpg)
![Survival of the Fittest](https://image.tmdb.org/t/p/w300/bsabO3soam3onaOXth0QZ8Ye16E.jpg)