When we humans feel very tired, we often say that we can fall asleep standing up, but this is just a description. In reality, it is impossible for humans to sleep standing up, but there are many animals in nature that have this such a skill that humans do not have, for example, horses can sleep standing up effortlessly.
The cave is so dark that these nocturnal snakes that live in bat caves are essentially completely blind and deaf
If you're in a vast expanse of desert, unless you can find water straight away, you'll be lucky to meet a camel. And it's not just the traditional image of the 'desert boat' that makes this animal so interesting - as a herbivore, they are almost never known to have natural predators in nature.
