Here on Earth, we have the moon’s gravitational pull to thank for the ocean tides, among other things. But what about moonlight?
The light reflected off the moon has an effect on life on Earth, which isn't surprising, but not every lunar influence is heralded by a wolf's howl.
Looking at a few examples of moonlight’s subtler influences reveals how much the moon has shaped life on Earth in unexpected ways.
The moon and animal behavior
Some animals, especially nocturnal species, have adapted their hunting and mating activities to the light of the moon. Some animals simply see better at night or are aided by the light of the moon. In contrast, prey animals know that to be seen means to be eaten, so it's prudent to hide when the moon is bright. And just as moonlight can influence predator-prey schedules, it also can influence some mating behaviors.
For example, certain species of badgers mark their territory more during the new moon, but during the full moon, they mark territory less. One explanation for the difference is that badger mating rituals are lengthy, so mating in the brightness of a full moon would put copulating badgers in danger. As a result, these badgers lie low during bright nights and are more active during other phases of the moon.
Many species of coral spawn on or near the full moon. While other factors such as weather and water temperature also influence their spawning, the event occurs near a full moon.
Doodlebugs dig bigger holes around the full moon. This could be because of the increased activity of prey when the moon brightens the night sky, causing a greater chance of catching dinner.
Certain owl species become more active during the full moon, both in their mating calls and in showing off their feathers to potential mates. In one study of the Eurasian eagle owl, researchers found the owls' feathers may be more visible in the light of a brighter moon.
The moon, plants and farming
The "werewolf" plant Ephedra foeminea only puts out a sugary residue to attract pollinators during the full moon in July. Researchers have yet to understand exactly how the plant "knows" to follow the lunar cycle, but research shows there's a correlation. There is, however, disagreement among scientists that the shrub's pollination is related to the lunar cycle.
Humans, of course, also rely on moonlight. We did this much more so before the creation of artificial light, but some things haven't changed entirely. Some farmers plant crops based on the lunar schedule. There's a debate among farmers about whether planting by the moon has any positive effect on crops but The Old Farmer's Almanac still offers a Gardening by the Moon calendar. The video above goes into detail about how that works.
Because the moon is so closely linked to life on Earth, it's difficult to know what's affected solely by the moon’s light and what's affected by additional factors, but its influence is undeniable. Why else would there be so many songs about it?
Editor's note: This story has been updated with new information since it was published in September 2015.