The Science Behind Christmas And Mistletoe

Christmas is almost here, and if you’re anyone who still follows yuletide traditions from ages ago, then you know what being caught under the mistletoe means.

But have you ever wondered why? Mistletoes aren’t exactly the most Christmas-y looking plant (that goes to pine trees, of course) so where did the tradition of kissing under it start?

It actually rooted from Norse Mythology. According to its folklore, Baldur (who is the younger brother of Thor) was the subject of a premonition made by Frigg, his mother. Because of this, Frigg then made sure that every object on Earth would take an oath to never harm her son, save for the mistletoe.

Loki, ever the trickster, exploited this, making a dart from the plant and tricking Hod (Baldur’s blind brother) to throw it at Baldur, killing him. Frigg’s tears then became the berries of the plant, and are now hung over doors as a sign of respect. The Celtic druids then adopted the plant as a symbol of fertility, combining it with the modern day Christmas period, as well as its association with the act of kissing.

Plant Thief

As an actual plant, however, the mistletoe is less than appealing since it’s essentially a parasite that steals water and nutrients from trees. Technically known as a “hemiparasite,” mistletoe seeds are usually spread by birds, which let them grab on to different trees and start using its resources for their own. However, some spread their seeds by other means, such as via small explosions that can blast seeds up to 15 meters away with the velocity of around 50 km per hour.

Thankfully, while the mistletoe acts as a parasite, it also has a use in the ecosystem its living in, with its berries often serving as food for birds and other animals during the winter time because they have the ability to grow in the middle of that period.

Another interesting fact is that while most plants grow towards the light, the mistletoe does the opposite, growing away from it. To infect the tree in any direction, it also ignores gravity.

mistletoe Mistletoe may bring Christmas kisses, but could it also give the kiss of death to cancer? Rupert Ganzer/Flickr