Legend has it that at this time of year the bridge between the living and the spirit world is at its smallest; and on Halloween spirits and fairies are able to cross over and spend the night walking in the land of the living. But don’t panic this has never been scientifically proven and a good Jack O’lantern will keep you safe.In Ireland people traditionally carved from turnips (sweed if you are from the south of the UK) or large potatoes to frighten away the spirit of Stingy Jack. The story goes that after repeatedly tricking the Devil, Stingy Jack was not allowed into heaven or hell but was given some burning coal which he put into a carved turnip to light his way as he roamed the earth for all eternity. The tradition of lantern carving was taken over to America with the Irish settlers. Pumpkins, native to North America, turned out to much easier to carve than turnips and make ideal lanterns. This week children and adults all over America will be carving pumpkins into Jack O’lanterns to mark the holiday. Now in the UK pumpkin carving has risen in popularity and is overtaking the traditional turnip carving. Pumpkin is a variety of the squash Cucurbita pepo. The name Pumpkin has no real biological definition and it used interchangeably with the name Winter Squash. The name Pumpkin tends to refer to the larger round orange versions. Pumpkin plants are Dioecious – meaning they produce separate male and female flowers. In 2012 America produced 12.4 Million cwt of Pumpkin1, to put that into a scale we all understand, that is about 55 000 Blue whales! That’s quite a lot of Pumpkin. Pumpkin is featured during the thanks giving dinner, usually in the form of pumpkin pie. Pumpkin seeds are a good source if nutritional magnesium, zinc and copper. The pumpkin also features as the carriage in Disney’s Cinderella, making popular the phrase “turn into a pumpkin” in reference to staying out too late.
Jack O’lantern is also the common name for the mushroom Omphalotus olearius. This mushroom is toxic to humans and is often mistaken for the edible chanterelle (Cantharellus cibarius). In the day the Jack O’lantern mushrooms appear orange in colour but in low light levels can be seen to glow a spooky green around the gills. This is a natural phenomenon known as bioluminescence and arises from the activity of an enzyme called luciferase that acts upon a molecule called luciferin and emits light in the process. This is the same process as occurs in the tails of fireflies. Luciferase is commonly used in biology to help identify which genes are switched on and how those genes are regulated. This is known as a reporter gene system. This enables scientists to understand what is happening at a molecular level just by looking at a cell through a microscope.
Have a happy Halloween everyone!
About the author: Kirsty Jackson is a PhD student at the John Innes Centre, Norwich. She studies bacterial and fungal symbioses with legumes and loves all things fungi! She also runs science outreach events. Follow her on twitter (@kjjscience)
1. Agricultural marketing resource centre US pumpkin yeild in 2012