Most people don’t welcome spiders in their home, but once they get to know the bold jumping spider, they might change their minds. Don’t grab the nearest shoe to smash it, don’t be put off by its looks. Despite having eight fuzzy legs and large iridescent green fangs, this spider is a helpful, tidy housemate.
Bold jumping spiders are pretty big– their bodies are about a quarter to a half-inch long. And though they may look fierce, they are harmless to humans. According to Penn State entomologists, your chances of being bitten by one are “slim to none.” The rare accounts of jumping spider bites suggest the bite causes a reaction similar to a mosquito bite.
But if you are an insect, these spiders are the stuff of nightmares- a lion stalking you in tall grass, poised to pounce… Unlike many spiders that spin webs, sit back and wait for insects to fly into them, bold jumping spiders are active hunters. In fact, they don’t spin webs at all, which means they won’t leave dusty cobwebs in the corners of your home.
Jumping spiders hunt during the day in open areas, such as walls and windowsills, using their keen eyes to spot their prey. Unlike other types of spiders, they have excellent eyesight and an almost 360-degree field of vision. The bold jumping spider will pounce on any insect smaller than itself, including houseflies, mosquitos, small crickets and other uninvited guests in your home.
Once prey is spotted, jumping spiders sneak up within striking distance– which for a jumping spider is pretty far. They owe their astounding jumping ability to hydraulics, not solely muscle. These spiders are able to rapidly increase the internal fluid pressure in their legs, propelling themselves 10-50 times their body length and pouncing on their insect victims. US Track and Field athlete Mike Powell, who holds the world record in the long jump, can jump less than 5 times his body length– and that’s with a running start.
Though bold jumping spiders don’t construct webs, they do make spider silk. They use a single line of silk as a tether to catch them in case they make a bad jump, kind of like a rock climber’s rope or bungee jumping cord. The female bold jumper also uses her silk to make an egg sac and small “den” where she hides with the sac and then her spiderlings when they hatch.
Jumping spiders are fun to watch– scientists who study their behavior believe they are very “intelligent” given the size of their brains. Most jumping spiders perform courtship “dances.” A couple of years ago a video of a colorful dancing spider went “viral” on the internet. The species shown in the video was the Coastal peacock spider from Australia– a species of jumping spider, just like our very own bold jumper.
Like a good guard dog, the bold jumping spider defends your home from intruders, albeit very small ones. But unlike a dog, that sheds hair and tracks in dirt, jumping spiders don’t leave a mess. So next time a jumping spider has moves into your home, consider letting it stay. While it can’t be counted on to help out with the rent or mortgage, it may still earn its keep.
This article originally appeared in the Grand Junction Daily Sentinel in September 2016.
I have a confession to make. I have a phobia of wasps and bees. Basically most of the order Hymenoptera, though ants bother me less- probably because they don’t fly (most of the time.) It’s a mild phobia. I don’t have the full-fledged panic attacks and disabling symptoms associated with severe phobias, though I have been known to exhibit ridiculous behavior, such as running, flailing and squealing, in the presence of bees and wasps.
I also have an irrational fear of hyenas. Hymenoptera, hyena. . . do I simply have an aversion to animals whose names start with “HY”? Nope. I think hyraxes are adorable and have neutral feelings towards tiny freshwater hydrozoans in the genus Hydra.
My fear of hyenas most likely stems from an experience I had in Tarangire National Park, Tanzania, when hyenas came into our camp site at night. I had taken my weekly dose of Larium, an anti-malarial drug notorious for sometimes causing bizarre dreams, anxiety, and in extreme cases, hallucinations.
I was awoken from a nightmare involving giant crabs by the noisy hyenas. They were just looking for stray bits of food, like a gang of 120 pound raccoons. But their garrulous snarling, squealing and loud breathing were hair raising even for my fellow campers who were not tripping on Larium that evening. I had also recently read a story in the New Yorker by Joanna Greenfield which detailed her attack by a captive spotted hyena. Great story, but don’t read it before you go camping in Africa. Seriously– don’t.
These irrational fears embarrass me. The hyena fear is less embarrassing because fear of a large, intelligent, predatory mammal that is fully capable of eating you and will give it a try if you look easy, is really not that irrational.
But a fear of wasps, bees and some ants is genuinely embarrassing because I am a biologist, I should know better. I hung out with lots of folks who study wasps and ants in graduate school and they taught me all sorts of cool things about their favorite insects. I learned about the evolution of eusociality, haplodiploidy, and all that fascinating stuff. (Back to hyenas for a moment. Female hyenas have pseudo-penises. Also fascinating, but doesn’t make them any less scary to me.)
I know that the likelihood that I would be killed or seriously injured by a stinging insect is very small. I am not allergic to bee stings. I am much more likely to be killed by a heatwave. I know that the mosquito, Aedes aegypti, is arguably the most dangerous animal in the world.
It’s not like I don’t encounter wasps and bees frequently. I enjoy the outdoors and spend much of my recreation time hiking, camping etc. I should be used to them by now. I have been stung on seven separate occasions. I know what it feels like. Yes, it hurts, but I have endured much worse pain.
I am not scared of many other creatures that people commonly fear. I enjoy catching (non-venomous) snakes with my 6 year-old son- a herpetology enthusiast. There are several black widow spiders living in my yard and I value their contribution to cricket control. I even touched a shark once while snorkeling. (It was a small, docile nurse shark resting in a coral cave, but you get my point.)
Yet hymenoptera– wasps especially– give me the heebie-jeebies. I have tried reasoning with myself. I know their evolution is fascinating, they serve important ecological functions etc., etc. Still they give me the creeps. If a wasp gets into my house and another adult is home, I will ask that person to get it out. If it falls to me to squash it, I will do the deed, but it will make me physically shudder. I will throw the body away but eye the trash can warily for the next couple of hours. If a wasp is trapped in my car, I WILL be pulling over and exiting the vehicle.
I am proud to have made some progress. I am much less fearful of honey bees than I used to be, and I will confidently capture and release them outside if they stray into my house. But there is no way in hell I will ever take up beekeeping or approach a wild honey bee colony. Africanized or “killer bees” are the stuff of my nightmares.
Speaking of nightmares, about 10 years ago I saw a segment in a nature documentary on the Japanese giant hornet that I have still not fully recovered from. I have trouble even looking at pictures of them. If I saw a dead giant hornet pinned and dusty in an insect collection, you’d have to pay me a large sum to touch it. If I ever had the opportunity to travel to Japan, these insects would make me think twice.
We’re admonished not to judge a book by its cover, but we do. (If we didn’t, a lot of graphic artists would be out of work.) So you can imagine how I felt when I received this book in the mail.
My brain sees this cover and says “Avoid! Avoid! Avoid!” There is a good reason for that. The wasp’s aposematic coloration, which is echoed in the jacket design, is intended as a warning to “stay away.” And the book explains how the hymenopterans’ sting– the danger that this coloration warns us about– allows these insects to exploit diverse environment and resources, and develop complex societies.
The book was sent to me by a publicist at Johns Hopkins University Press, which published it. I had recently written a post for Entomology Today about a study on harvester ants in which I quoted the book’s author Dr. Justin Schmidt. This caught the generous publicist’s eye and she asked if I’d be interested in a copy. I was flattered. No one ever offered me a free book, except when they were trying to religiously convert me.
Of course I’d like a copy! Who can turn down a free book? I realized she probably wanted me to read it and write something about it, but I put that out of my mind. The book arrived and it sat on my nightstand– upside down so I didn’t have to look at the wasp on the cover.
But if I do occasionally (frequently?) procrastinate, in the end I am generally dutiful. So I read “The Sting of the Wild” and I enjoyed it. Schmidt, an entomologist at the Southwestern Biological Institute, is an excellent writer. He can write clear, engaging explanations of sting evolution and venom chemistry, as well as spin a good yarn about his adventures collecting stinging insects. I enjoyed his dry, judiciously applied, wit.
Schmidt is most famous for the “Schmidt Sting Pain Index” which is published in its entirety for the first time in this book. He has painstakingly (emphasis on the pain) documented the stings he has received from various species of hymenoptera. In many cases, he has actively sought stings from certain species in order to add them to his index. The pain delivered by each sting is given a quantitative rating of 1-4, as well as a qualitative, often poetic, description. Some examples:
Western yellowjacket: Hot and smoky, almost irreverent. Imagine W.C. Fields extinguishing a cigar on your tongue. Pain level 2.
Dasymutilla klugii (a huge velvet ant): Explosive and long lasting, you sound insane as you scream. Hot oil from the deep fryer spilling over your entire hand. Pain level 3.
So is Schmidt just a sadomasochist with literary flair and a thing for collecting data? What would compel someone to get stung on purpose in order to make an index of pain? Science would.
If you quantify something, you can compare it to other somethings. Schmidt’s Sting Pain Index allows him to make and test predictions about insect’s stings. Why does a harvester ant’s sting (pain level 3) hurt so much, but the sting of a large, intimidating-looking cicada killer wasp (pain level 1-1.5) hurt less than the common honey bee? The answer has to do with their life history, the predators they face and the food they eat.
Stinging hymenoptera don’t want to sting you. In fact, they generally give you fair warning to stay away. Aposematic coloring and patterns of high contrast yellow, white, red and black are just one of the signals these insects use to say “leave me alone.” Schmidt also describes auditory warning signals, including loud buzzing and stridulations, as well as olfactory messages.
(This information actually made me feel better about my fear. I’m not irrational, I’m just a good listener. I am simply respecting stinging insects’ requests that I stay away.)
So take it from someone who didn’t initially want to read “The Sting of the Wild” but found it captivating (and a bit spine-tingling)– this book is worth your time. Justin Schmidt is a science hero in my eyes (I would love to know what gives him the creeps.) Creating a “Sting Pain Index,” would be for me a task akin to navigating Dante’s nine circles of hell.
This is a man who has methodically documented the sting of a tarantula wasp (pain level 4). His advice if you are unfortunate enough to be stung by this giant iridescent insect is to “lie down and scream”:
The pain is so debilitating and excruciating that the victim is at risk of further injury by tripping in a hole or over an object in the path and then falling onto a cactus or into a barbed-wire fence. Such is the sting pain that almost nobody can maintain normal coordination or cognitive control to prevent accidental injury. Screaming is satisfying and helps reduce attention to the pain of the sting.
Schmidt endured that sting and many, many others. And he did it for science.
About a year ago I started writing occasional articles for the Entomological Society of America’s website “Entomology Today.” These assignments prompted me to delve into some biology I might not have otherwise and it has been so much fun. I’d like to share my entomology articles with my blog readers by posting links to them here. If you are interested, check out what I am doing over there. I hope you enjoy it.
Here’s a look at the diabolical biological weaponry predators and parasites use against one another. Click on the killer photo by entomologist and photographer extraordinaire, Alex Wild, to read the article.
Let us give thanks that humans are much larger than praying mantids. If a praying mantis got any larger it would be downright terrifying. Their front legs, held in the “prayer position” that gives them their name, are actually lethal weapons. Lined with sharp spikes, they shoot out with lightning speed and snatch an unsuspecting insect, then hold its struggling body as the mantis devours it alive. The mantis relies on these “raptorial forelegs” and its camouflage to catch its prey. It is a “sit-and-wait” predator, perching motionless and blending into the foliage until an insect wanders within grabbing distance.
In our area, mantids don’t get very large, about four and a half inches of fierceness at most. But large mantids may eat hummingbirds when they get the opportunity. Mantids are also famous for cannibalism. Females are known to eat their mates, sometimes even during the mating act—but only if she is really hungry. Don’t feel too sad for the male mantis though, his life would have been short regardless of his mate’s appetite. Mantids live about a year at most and do not overwinter. After mating, female mantids lay a clutch of eggs and then die. The eggs are protected in a gob of what looks like brown Styrofoam. You can find these egg masses on twigs, weed stalks and even the sides of buildings or fences. In the spring, dozens of miniature mantids will emerge from the egg mass and head out to hunt.
Mantids are often green in color to blend in with summer leaves, but some species may be speckled grayish-brown later in the season when vegetation dries out. As the mantids grow larger, they molt their skin. With each molt they may adjust the color of their skin to match their habitat. Mantids are masters of disguise and can be hard to spot, especially when they are tiny. In our area they seem to be much more common in the late summer and fall, but really they have been around since spring. It is just that they have finally gotten large enough to spot easily. It is also easy to determine if an adult mantis is male or female. Females have a wide abdomen for producing their large egg masses, whereas males have a slender abdomen allowing them to fly more easily.
Finding a praying mantis is your garden is definitely a good thing, they are harmless to humans and eat pests. But contrary to popular belief, mantids are not really suitable as biological control insect. They will not naturally rid your garden of all those pesky squash bugs and hornworms. That’s because mantids aren’t picky eaters—they’ll eat anything, beneficial insects, pests and other mantids. And because they can’t reproduce quickly, producing young just once a year, their populations can’t boom when the pest populations boom.
But a praying mantis is nice to have around simply because it is fascinating to watch. Their movements are oddly mesmerizing. With large eyes and an ability to rotate their heads 180 degrees, they seem, if not human-like, at least movie-alien-like. And it’s not just modern gardeners who are fascinated by the mantis. Many ancient cultures considered them gods and the word “mantis” derives from the Greek word for diviner or prophet. In China, two styles of martial arts were based on the movements of the mantis.
Next time you spot a praying mantis, take some time to watch this intriguing insect. And give thanks that it is not bigger, and you are not a fly or whatever careless insect it’s planning on having for dinner.
This post originally appeared in edited for in the August 22, 2015 issue of the Grand Junction Daily Sentinel http://www.gjsentinel.com