The Wild is ever vigilant. Sleep, that deep, profound, dream-laden land of Morpheus, is forbidden The Wild by evolutionary design.
Pets are embraced by Morpheus (at least, should be. Some people don’t deserve pets) because modern pets – those not kept outside or in a barn – recognize the safety within the walls of home.
Their den, as it were.
When your cat purrs in its sleep, when your dog woofs and twitches, when your bird tucks its head under a wing, it communes with its kin through all time knowing such journeys undertaken are safe.
Not so in The Wild.
There evolution forbids deep rest because deep rest equates to being prey.
Western cultured two-Leggers have only enjoyed deep sleep (many, anyway. Definitely not most or all) for perhaps the past two-hundred years, basically since the industrial revolution, when group recognition fell from village or tribe and climbed to housing project or job.
Light sleepers’ non-conscious minds remember The Wild and pay attention.
Do you?