13. Meerkats
Meerkats are famous for their tight-knit social groups and cooperative habits—even when it comes to sleep. They rest together in cozy, underground burrows, where warmth and safety are guaranteed.
While most of the group sleeps, a few vigilant meerkats take on the crucial role of sentinels, keeping watch for danger. This rotating system of guard duty ensures the whole colony stays protected from predators lurking above ground. National Geographic