CLOSE
Original image
ThinkStock

How Spiders Win the Lottery

Original image
ThinkStock

On a cloudy spring day, a little spider scales a tall blade of grass. At the peak, the spider arches up, points its abdomen up to the sky and begins releasing strands of silk from its silk glands. Tens of thousands of strands fill the air, fanning out and then coming back together to form a triangular sheet. A passing breezes catches the silk and suddenly the spider is airborne, riding its homemade parachute into the wild blue yonder.

Spider use these “ballooning” flights to escape from danger and to colonize new habitats. Most times, they only travel a few feet, but the right conditions can carry a spider over vast distances. Sailors have found them landing on ships thousands of miles from shore, and scientists have discovered eight-legged travelers in air samples collected by atmospheric data balloons.

All sorts of tiny arthropods travel this way, and some plants and fungi also use the wind to spread seeds, spores and pollen. Scientists call it passive airborne dispersal and from our perspective, passive is the key word. The tiny flyers seem to be left at the mercy of the elements and there seems to be little opportunity for them to strategize or make the most of their trip. The direction and distance they travel—or whether they travel at all or get stuck waiting to take off—are decided by the movement, direction and speed of the air.

Some researchers dub it the “aerial lottery.” The flyer buys their ticket, catches a breeze and crosses their metaphorical fingers that they land safely in a place they want to be. Whether they’ve won (new habitat, safe from danger, yay) or lost (atmospheric data balloon, boo) isn’t revealed until they’ve landed, and by then their play is over.

The journey appears completely out of their hands, yet many passive dispersers wind up exactly where they should want to be: still sort of close to where they started (where there are reliable, if shrinking, resources), but away on their own with untapped resources and no competition from their fellow spiders/seeds/whatever-they-ares. This winning play is the “shortest unique flight,” similar to the “lowest unique bid” needed to win some auctions and games. Despite all appearances, then, there may be a way to improve one’s odds of winning.

The trick to winning the aerial lottery, scientists think, is all in the take off, the last stage of the game where the “player” still has some control. Plants and fungi have been known to launch their wind-dispersed pollen, spores and seed only in certain conditions. Spiders and other wind-sailing critters, meanwhile, can choose the time and location of their launch.

New research by Andy M. Reynolds from the UK’s Rothamsted agricultural research station suggests that a winning strategy is based on taking flight in specific weather conditions. Warm, gentle breezes on days with some cloud cover are ideal for making the shortest unique flight. In more stable conditions the flight might be unique, but will last longer. In less stable conditions, the flights are shorter but less likely to be unique. The ideal launch seasons, Reynolds suggests, are spring and autumn, exactly when spiders tend to ramp up their “ballooning behavior.”

Whether these creatures win or lose at their lottery is more relevant to us than you might think at first. Spiders are a great help in controlling pests, and knowing where and when they take flight can benefit farmers. “Each day of the growing season around 1,800 spiders land in each hectare of arable farmland after ballooning,” Reynolds said in a statement about the study. “If the farmers can predict the influx of spiders, they can reduce the amount of pesticides accordingly," saving money and hassle. Similarly, being able to predict the spread of problematic fungi can help control them and the diseases they cause, giving us a leg up in this strange game of chance.

Original image
iStock
arrow
Big Questions
Do Cats Fart?
Original image
iStock

Certain philosophical questions can invade even the most disciplined of minds. Do aliens exist? Can a soul ever be measured? Do cats fart?

While the latter may not have weighed heavily on some of history’s great brains, it’s certainly no less deserving of an answer. And in contrast to existential queries, there’s a pretty definitive response: Yes, they do. We just don’t really hear it.

According to veterinarians who have realized their job sometimes involves answering inane questions about animals passing gas, cats have all the biological hardware necessary for a fart: a gastrointestinal system and an anus. When excess air builds up as a result of gulping breaths or gut bacteria, a pungent cloud will be released from their rear ends. Smell a kitten’s butt sometime and you’ll walk away convinced that cats fart.

The discretion, or lack of audible farts, is probably due to the fact that cats don’t gulp their food like dogs do, leading to less air accumulating in their digestive tract.

So, yes, cats do fart. But they do it with the same grace and stealth they use to approach everything else. Think about that the next time you blame the dog.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

Original image
iStock
arrow
Animals
Squirrels Are Probably More Organized Than You, Study Finds
Original image
iStock

Despite having a brain that's slightly bigger than the size of a peanut M&M, squirrels have a fascinating, razor-sharp instinct when it comes to survival. They know that acorns that are high in fat and sprout late are perfect for long-term storage, so they salvage them for winter and eat the less nutritionally dense white-oak acorns right away. They also tend to remember where they put their acorn stash rather than relying solely on smell. Like nature's perfect stunt performer, they can even fall out of trees in a way that minimizes physical damage. Now, researchers at the University of California, Berkeley have unveiled a newly discovered part of a squirrel's hoarding strategy, Atlas Obscura reports.

The researchers tracked 45 wild fox squirrels on the UC-Berkeley campus for nearly two years. They made available to the squirrels four different types of nuts—walnuts, pecans, almonds, and hazelnuts. Sometimes the animals were given a single type of nut, and other times the nuts were mixed. Either way, the squirrels promptly sorted and stored their food according to type—walnuts went in one hiding place, almonds in another, and so on.

This type of behavior is known as "chunking" and makes it easier to retrieve data in memory. In doing this, a squirrel won't have to visit several different places looking for pecans: They know just where the main supply is. Squirrels can stockpile up to 10,000 nuts a year, so it's essential for them to know which type of nut is where.

The study, published in Royal Society Open Science, also indicated that squirrels seem to understand nuts have weight, choosing to carry heavier acquisitions to a different location than lighter nuts.

Squirrels being squirrels, they were happy to be gifted an assortment of nuts during the experiment, but there was one wrinkle: Rather than stash them away, sometimes they'd just eat them on the spot.

[h/t Atlas Obscura]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios