Throughout history, the influence of the full Moon on humans and animals has featured in folklore and myths. Yet, it has become increasingly apparent that many organisms really are influenced indirectly, and in some cases directly, by the lunar cycle. Here are ten things you may not know about the way the Moon affects life on Earth.
- Palolo worms, a gastronomic delicacy in seas around the Samoan Islands, emerge in vast numbers to be caught by local fishermen only during days of the third quarter on the Moon in October or November.
- Common Green Crabs transferred from a rocky sea coast to a marine aquarium continue to “sleep” at intervals coinciding with times when the Moon-driven tide has ebbed on their home beach.
- Sea Lice which live in beach sand near high water mark during spring tides avoid being left high and dry during neap tides by swimming up, fortnightly, into the falling tide, timed by their own internal biological clocks of Moon-related periodicity.
- Wideawake Terns on Ascension Island in the equatorial Atlantic Ocean – where seasonal changes in day-length are small – return to the island to breed after every tenth lunar month, not every calendar year.
- African Scarab Beetles are able to roll to safety, for later consumption, balls of elephant dung, travelling in straight line directions determined by the position of the Moon.
- Young stages of an insect, the Ant Lion, excavate funnel-shaped pits in sand into which fall other insects which are captured as food. The Ant Lion builds larger pits during Full Moon, when prey insects would be more wary, and does so even if it is prevented from seeing the Moon.
- Sandhoppers foraging in sand dunes on Mediterranean beaches are able to navigate accurately to the strand-line at night using the position of the Moon, compensating for the changes in position of the Moon by use of their own internal lunar clockwork.
- Beach-living Midges swarm to mate randomly if they are unable to see the Moon, but exposure to moonlight for three nights only induces fortnightly mating swarms, by setting in motion the midges’ internal Moon-related biological clocks.
- Young Shore Crabs moult just after full and new Moon and continue to do so in aquaria when they are unable to see the Moon.
- Human volunteers isolated from time cues in a sleep laboratory fall asleep more quickly during nights of the New Moon.
Featured image credit: Super moon, by Blondinrikard Fröberg. CC-BY-2.0 via Flickr.