Why animals sleep
Like humans, most animals need sleep to function effectively. Some sleep for a few minutes whilst others sleep for up to 20 hours a day. Here in Oman, land mammals generally sleep, quite sensibly, during the day to avoid the heat. Tucked away in shade, Oman's terrestrial mammal fauna are safe from predators, conserve energy and even preserve water by remaining inactive during the day. Carefully constructed burrows also ensure that water vapour in exhaled breath condenses on the inside of the shelter, reducing the need to find rainwater or morning dew. Sleeping in a hidden burrow also makes the animal less likely to be discovered by predators. Smaller animals have faster metabolic rates and so must wake regularly to feed. Keeping a store of food, either in the equivalent of a larder, or as fat reserves on the body, helps to minimise the amount of time the animal needs to spend out in the heat of the day.

Turtles in the dark
When turtle hatchlings emerge at night from their eggs and head for the ocean, lights from hotels and other sources can lead them off course. Sometimes the hatchlings get killed walking in the wrong direction as they attempt to cross road. If their long night's journey stretches into day, the turtles often die of exposure or fall victim to hungry predators.

Online resources
The International Dark-Sky Association, www.darksky.org, aims to:

• Stop the adverse effects of light pollution on dark skies, including:
• Energy waste and the air and water pollution caused by energy waste
• Harm to human health
• Harm to nocturnal wildlife and their ecosystems
• Reduced safety and security
• Reduced visibility at night
• Poor nighttime ambience
• Raise awareness about light pollution, its adverse effects and solutions
• Educate everyone, everywhere about the values of quality outdoor lighting
• Help stop other threats to our view of the universe, such as radio frequency interference and space debris
• To reach out and identify communities with exceptional commitment to and success in implementing the ideals of dark sky preservation and restoration, and their promotion of quality outdoor lighting