How does Minho react to the major change in the Gladers' enviroment?

Minho reacts by immediately going back to study the maps they've been making along the way. Thomas is shocked that he didn't tell Alby and Newt first, but Minho takes charge. As a runner, he wants to check everything thoroughly.

He ran off the side of the cliff and passes away...

Minho got shocked and scared, so he quickly ran to the maps to make sure he heard right, but he should of told Thomas and Alby, because Alby is the leader and Thomas is the smart one that has been through the Changing and the Maze, but he is a runner and so he acts fast and dies what he thinks is best within the moment something has happened.