Studio Wildcard has announced that the XBox One version of ARK: Survival Evolved will feature local split screen cooperative action. It won't, however, be available for tomorrow's release but will be patched into the game in early 2016. Cooperative split screen is already working on internal studio machines and looks like this:
In other big news, XBox One players will be able to use a second machine that will allow the creation and hosting of private game servers. This will be available for tomorrow's release.
Source: Gamespot