Ants stretch and yawn when they wake up.
Famous entomologist (insect scientist) Derek Wragge Morley noted a lot of unusual behavior in ants. For instance, when they wake up they stretch out all 6 of their legs and then open their mandibles as if they are yawning.
Ants also have different personalities. Ants in the same species and colony can exhibit the characteristics of stupidity and laziness, or they can be smart and hardworking. If the hard workers are removed from a colony, the entire colony will suffer.
You know how ants from different colonies always fight each other? If you take young ants from hostile colonies and make them live together, they actually cooperate and don't fight.