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After the player's species evolves its brain capacity far enough, it enters the tribal phase. At this stage physical development ceases (as does the player's direct control over an individual creature), but the player is given a hut and several of the creatures designed in earlier phases. The player also gains a mini-map of the world for the first time.

At this point the game is similar to a real-time strategy game in that the player can order the tribe members to move, attack, etc. The player may give these creatures tools such as weapons, musical instruments, and campfires, purchased with food that the tribe has gathered (replacing DNA points as the game's currency). The creatures' behaviors and personalities are affected by what tools the player decides to give them. Creatures also gain the option to wear clothes that demarcate their professions; for example, recruiters wear recruiting clothes while farmers wear farming clothes. At this point, tribe-to-tribe contact can take place, should the player choose to (whether that contact be diplomatic or violent - the July 10, 2007 IGN "Evolution" video featured a battle between two tribes of the same species, but with variations in their skin colourations. The player may also "tame" other non-intelligent creatures, and even use them as livestock. Domesticated creatures seem to undergo neoteny in contrasting photos of the same species, but it is unknown whether it is automatic or if the player was permitted to edit tamed creatures in the editor.

Once the tribe reaches 15 members, the player can choose to progress to the civilization phase.

The main unit of currency is Food.