BY SASHA GREENSPAN
What’s a blue moon? Does it really look blue?
Most calendar years contain twelve full moons to correspond with the twelve months, but sometimes those extra days line up in such a way as to put two full moons in one month. It only happens about every two or three years—hence the expression “once in a blue moon.” Blue moons by these definitions don’t actually appear blue, but excessive smoke or dust in the atmosphere, as from a volcanic eruption, can give the moon a blue tint. This happened in 1883 during the catastrophic eruption of Krakatoa, a volcanic island in Indonesia. The eruption killed over 35,000 people and was said to be heard from thousands of miles away. So, if you ever happen to find yourself gazing up at a blue moon, don’t dally. You can enjoy the view while you pack for your evacuation.
Why do lizards often appear to be doing push-ups?
Male lizards are intensely territorial and make complex displays by head-bobbing, doing “pushups,” and opening their mouths to claim territory and attract mates. It’s the reptile equivalent of squeezing on your skimpiest, shiniest spandex and taking the mat closest to the gym window. According to Florida International University herpetologist Steven Whitfield, many species, such as the Green Anole of the Southeast U.S, also have a colorful throat fan that can be extended while doing these territorial displays to increase visibility to females or competing males. When you’re green or brown and live in a green-and-brown world, you have to go out of your way to get noticed.
Reptilian aerobics routines may sound funny, but they hardly skim the surface of weird mating rituals found among lizards. For example, all whiptail lizards are female and reproduce by parthenogenesis, meaning all offspring are clones of the mother. Individuals engage in what is known as pseudocopulation, in which a post-ovulatory lizard mounts a pre-ovulatory lizard to stimulate egg production.
What is foxfire, and why does it glow?
Those tiny twinkles in the soil that light up your night hikes are thanks to fungi doing what they do best: decomposing dead stuff. Foxfire refers to fungi in the genus Armillaria that are commonly found in soil and woody debris throughout the United States. Mushrooms are the parts of fungi that we are most familiar with, but the bulk of a fungus is a matrix of thin filaments called mycelium, which behaves much like meandering plant roots to exploit nutrient and water resources. You may only see a few mushrooms here and there, but a single mycelium can cover over thirty acres, making some fungus species the largest organisms on Earth. So move over, cockroaches, because fungi have already taken over the world. We just don’t notice because they are usually lurking below the soil surface.
The decomposition of organic matter by Armillaria species of fungi involves a unique chemical reaction, the result of which is bioluminescence, light emitted by living organisms. The mycelia contain the specialized chemicals luciferin, which releases light when it reacts with oxygen. This type of reaction is found in all sorts of organisms, from fireflies to deep-sea squid.
“The biological purpose of bioluminescence has been greatly debated,” explains Dr. Kim Coder of the University of Georgia, but some hypotheses are that bioluminescence allows excess energy to be released without producing heat or that bioluminescence absorbs free radicals that could be a threat to fungal tissue.
Send your questions about the natural world to firstname.lastname@example.org.