Best housemate ever: The Bold Jumping Spider

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What a face! The bold jumping spider’s large eyes provide keen vision. Its striking iridescent green fangs are likely for show. Photo by Opoterser, Wikimedia.

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 screen-shot-2017-01-24-at-3-17-06-pmvery “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.

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Best housemate ever: The Bold Jumping Spider

The scorpion’s softer side

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Northern Scorpion. Photo by Meredith Swett Walker

It is hard to think of a creature less likely to inspire warm, fuzzy feelings than the scorpion. They have pincers, an intimidating stinger, and are rumored to hide in shoes. Plus, they are hard to categorize and this makes humans uncomfortable. Is a scorpion an insect? Is it a crustacean like a crab? They look “crunchy”, “pinch-ey” and “stingy” all at once.

It turns out that the unlovable scorpion– which is neither insect nor crustacean– has a softer side. These creepy crawlies turn out to be caring mothers. Their venom may help scientists develop important medications. Though they cause many people to shudder, scorpions deserve a second look.

Scorpions are arachnids like spiders, and like spiders they have eight legs. The two front limbs that bear their pincer claws are technically “pedipalps,” not legs, and are not used in walking. While scorpions may look like an alien visitor from a chilling sci-fi film, they have walked the earth longer than almost any other animal. Scorpions evolved at least 430 million years ago, long before the dinosaurs. In fact, the oldest known fossil of a land dwelling animal is a scorpion found in 2013 in South Africa.  Modern scorpions are found on every continent except Antarctica.

Clearly scorpions have mastered the art of surviving on planet Earth and the secret of their success may be their low-key lifestyle. They are nocturnal and hide from daylight under rocks or in burrows, emerging at night to hunt insects. But scorpions are essentially “couch potatoes.” They have a very inactive lifestyle and a low metabolic rate which means they require very little energy or food. Unlike human couch potatoes, scorpions can go a long time without a meal. Some species have been reported to go up to a year between feedings.

Yet scorpions are not slackers in the parenting department. Female scorpions give birth to live young rather than lay eggs. The newborn scorpions are defenseless– their screen-shot-2017-01-14-at-12-23-12-pmexoskeletons do not harden until they are older so their pincers are soft and useless and their stingers are blunt. To keep them out of danger, mother scorpions carry their babies around on their backs until they are old enough to defend themselves.

Scorpions sometimes use their stingers to subdue prey that they catch with their pincers. They will also sting in self-defense, and if they feel the need to defend themselves from your incoming foot– you may be in for some pain. Most scorpion stings are no more painful than a bee sting and ultimately harmless. Only one scorpion in the U.S. has venom powerful enough to cause life-threatening illness in humans. The Arizona bark scorpion, which is found in the Sonoran Desert, has a neurotoxin in its venom that can cause extreme pain and numbness. But fatalities due to its sting are rare.

Scorpion venom may turn out to provide more benefit than harm to humans. The venom contains a number of different chemicals that have potential as drugs. Scientists are currently investigating components of scorpion venom that may be useful in treating brain tumors and malaria. Who knows what other secrets may hide in the scorpion’s stinger?

Though there are plenty of scorpions in the Grand Valley, they keep a low profile and are seldom seen. If you do encounter a scorpion, before you run away shrieking or stomp it to smithereens, take a breath and consider letting it go its merry way. These secretive creatures are less menacing than may they appear.

This article was originally published in the Grand Junction Daily Sentinel in May 2016

The scorpion’s softer side