Some animals don’t sleep laying down? Well, the animals we are familiar with are sleeping laying down most of the time.
In the zoo, the animals are not alert. They know that they can relax since there are no more threats, and pleasures are guaranteed. The amount of pain and pleasure goes in the opposite direction compared to the wild environment: pain = down, pleasure = up.
Happily giving up being hyper alert and aroused, they are now busy enjoying the once-impossible luxury: sleep as much as they want. Have they forgotten to run? Have the forgotten to hunt?
What happened to them?
We now tap in to the Yerkes-Dodson Law. The Yerkes-Dodson Law is an empirical relationship between arousal and performance. It assumes that humans tend to perform best when we are moderately aroused: not too bored, not too stressed.
What if we apply this theory to explain what happened to the animals in the zoo?
In the wild the animals always have to be alert and aroused to prepare for the unexpected and emergencies. They have incentives to stay so to increase their odds of survival.
But once in the zoo, the incentives suddenly disappear. Their arousal level shifts towards a lowered state of alertness.
Conceptual State of Animals in Nature vs. Zoo
Next to “mildly alert” on the curve is “boredom”. Does this mean that the animals in the zoo are bored?