You know how in the True Ending ERC-003 sacrifices itself so animals can continue to inherit the earth? In Survival Mode, if you survive for 100 years Homo Erectus arrives, and they're everywhere. They're a worse Zerg Rush than the lions, and you'd be hard-pressed to find any other animals in the game world at that point. While it's probably just the game screwing you over so the average player won't make it past 200 years or so and not see any humans of the present or future once the year 2215 hits, if it's canon it heavily implies that ERC-003's sacrifice was all for nothing, effectively turning the ending into a Shaggy Dog Story. At least its wolf buddies managed to live out their lives.