Venomous snakes, spiders and scorpions are often portrayed as villains of the animal kingdom. Their appearance can be sinister, their toxins deadly. But their threats to humans are often greatly exaggerated. Venomous snakes, for example, make up just 10 percent of snakes worldwide [source: University of Massachusetts Amherst].
If you live in the United States, you're nine times more likely to be struck by lightning than to be killed by a venomous snake [source: University of Florida]. About 8,000 people get venomous snakebites each year in the United States, about a dozen die [source: Juckett and Hancox].
So why do these animals terrify so many people? In the case of snakes, few creatures are more different from humans: no arms, no legs, no eyelids. That anatomy and those stares creep some people out. While Aztec and some African cultures revered snakes, Judeo-Christian beliefs that tie serpents to Satan in the Garden of Eden contribute to wariness about them.
Depending on where you live -- unless you live in a very cold climate -- chances are you may run into one of these animals in your backyard. Best advice: Leave them alone. Most people are bitten when they try to pick up or kill the animal. Also remember the last thing these creatures want to do is waste precious venom on something they can't eat. Venom takes a lot of energy to make, so unless their lives are in immediate danger, they would much rather hide or scurry away.
In this article, we'll find out more about 10 venomous creatures that may be in your backyard, and how to stay safely away from them.
Scary enough name?
This venomous scorpion, found in Africa, Asia and the Middle East is 4 to 5 inches (10.2 to 12.7 centimeters) long, and is usually found hiding under rocks or inside small burrows in dry and desert areas.
During the night, this arachnid can usually grab its prey, like crickets and mealworms, using just its claws. But if it needs more firepower, it can use its tail to deliver extraordinarily toxic venom.
This scorpion kills several people each year, primarily children [source: Rein]. Its neurotoxin moves through the body quickly, causing extreme pain, fever, convulsions, paralysis and sometimes coma and death. An antivenom does exist.
The provocative name makes this animal tempting to adventurous but poorly trained animal collectors. Kansas State University entomologists warn that pet stores import many species of scorpions from around the globe, often with little knowledge about how dangerous they might be. Anyone stung by this scorpion should get immediate medical attention.
When left to the professionals, this scorpion's highly toxic and complex venom could be a possible treatment for brain cancer. Clinical trials are underway on patients with malignant glioma, the cancer that killed Sen. Edward Kennedy [source: Conova].
Read on to find out how less threatening names don't always mean harmless stings.
Plenty of picnickers have gotten a nasty surprise when they've taken a swig of a soft drink and gotten a painful sting on the lips, mouth or throat from an angry yellow jacket. These small wasps are attracted to sweet smells, and also to the odors of meat and fish. So, they hang around garbage cans as well as crash garden parties.
They're social insects, found in temperate areas across North America. Nests can be found in attics, walls, log piles, even in abandoned animal burrows, usually with 500 to 5,000 insects. And if the worker wasps perceive a threat, they'll attack intruders.
Only female yellow jackets have stingers, which are attached to their abdomen. While bees die after they've injected a victim, the stingers on wasps, hornets and yellow jackets remain on their bodies, so they can sting again and again.
While the natural reaction may be to swat and flail your arms as these insects fly toward you, that will likely get them more agitated. Just walk away.
The CDC estimates 90 to 100 people die each year from insect bites due to severe allergic reactions known as anaphylactic shock [source: CDC].
If you keep your distance, this insect is a plus for your immediate surroundings. They eat lots of flies and mosquitoes.
The name may sound rather flimsy, but these wasps can pack a punch. Their nests are easy to recognize hexagonal, paper honeycombs with deep holes for larvae. They can make a nest just about anywhere -- under building overhangs, or inside metal gutters and outdoor grills. Their long, thin bodies, about an inch (2.5 centimeters) long, are usually reddish brown, with some yellow markings, and they look smooth and hairless.
Mature nests may house 20 to 30 adults, who forage during the day.
Like most venomous creatures, stinging a human is usually a last resort for wasps. It can happen if they're captured, touched, or if they sense the nest is being threatened. Males are harmless, but females can sting people or pets multiple times. Severe allergic reactions can sometimes lead to death.
Gardeners consider these insects beneficial, because they do eat caterpillars, flies and beetle larvae. Be most aware of these creatures during the summer. By late summer, the queen stops laying eggs and the colony begins to die off.
These wasps build new nests every year, but often in the same location as an earlier successful nest.
A sting that feels like a gunshot? Keep reading!
If your backyard is in Central or South America, these ants could be your worst enemy. Their sting is as piercing as a bullet. The insects are also known as 24-hour ants, "because people believed if you were stung, you only had 24 hours to live," said Randy Morgan of the Cincinnati Zoo.
While the stings don't do any permanent damage, Morgan says the pain of the world's most venomous insect is excruciating for three to five hours. Add to the severe pain: trembling, perspiration, nausea, and uselessness of the injured arm or leg. Morgan has used antihistamines, an ice pack and sleep to get through the pain, while others self-medicate with alcohol.
As tough as it might be, he suggests trying to keep calm and not hyperventilate.
As intensely painful as one bite can be, some South American Indians actually intentionally inflict the bites of dozens of these inch-long (2.5-centimeter-long), reddish-black ants on teenagers in tribal manhood rituals [source: Morgan].
Among entomologists, the bullet ant is well respected for its ferocity. Justin Schmidt of the Southwestern Biological Institute has a misery rating of insect stings, from zero to 4. The bullet ant ranks an agonizing 4-plus.
What do Brazilian spiders and erectile dysfunction drugs have in common? Keep reading.
The wandering aspect of this aggressive spider can be especially scary, because it's known to scurry from forests to backyards to bedrooms. It's also known to hide in clothes and shoes during the daytime, and has been found in highly populated cities including São Paulo and Rio de Janeiro in Brazil.
In the wild, across Central and South America, this arachnid wanders across the forest floor. It doesn't make a web or stay in one place. It hides in logs and rocks, banana plants and termite mounds.
Although people are often more afraid of spiders than necessary, there's good reason to be afraid of the Brazilian wandering spider -- its bite can be deadly. In fact, it's listed in the Guinness Book of Records as the most venomous animal because of its toxin.
There's a strange impact of the spider's venom when the victim is male: priapism, or a lengthy and painful erection. Brazilian emergency room staffs know immediately the source of a sting when men or boys arrive with intense pain, high blood pressure and an uncomfortable erection.
Outhouses, mystery novels and Halloween parties: Read on to learn more about the intrigue of the black widow.
Legendary. Notorious. Always a scary element at Halloween parties. This spider is actually pretty timid, but its bite can be ferocious. A black widow's venom can cause cramps, difficulty breathing, nausea and even death.
Black widows are found in warm regions around the world. The female is black with a distinct, reddish, hourglass-shaped marking on her abdomen. More than 25 species worldwide eat insects and other spiders trapped in their webs.
One lifestyle change led to a dramatic decrease in black widow spider bites: indoor plumbing! Since the spiders no longer have outhouses to spin their webs in, people now encounter them doing yard work or near piles of firewood [source: Barnes].
Only the females bite, and do it only defensively, when touched or disturbed.
The most common myth about the black widow is that the female eats the male. It happens, but usually when the animals are in captivity and the male cannot escape. Females are typically twice the size of males.
When you see a web, don't get too close, and always assume a spider is on it. Once a web is built, these spiders tend to stay put. They are awkward and unsteady when they're forced to leave it.
This is the king of venomous snakes. Up to 18 feet (5.5 meters) long, the king cobra is extraordinarily fast when it strikes. It can be found around bamboo, mangrove swamps, tea plantations, and forests in India, China and Southeast Asia.
Its signature, fear-inducing mechanism is a hood, a combination of muscle and rib action in the neck that spreads loose skin and makes this reptile look menacing. Its ritual to scare away possible predators is to stand, spread out its hood and hiss loudly. The trick usually works.
Their fangs are about 0.5 inches (1.3 centimeters) long, and unlike vipers, cobras cannot hold their fangs down. But their bite can be powerful. The venom is a neurotoxin that acts on the nervous system and can stop a victim's breathing and heartbeat. And if they're not scary enough on land, these snakes can also climb trees (like many snakes) and are excellent swimmers.
Their size and the amount of venom they produce can be enough to kill an elephant [source: Philadelphia Zoo]. King cobras kill about five humans a year.
This snake has one natural enemy, the mongoose. This small, carnivorous mammal has the speed, agility and fearlessness to bite the back of the cobra's neck.
Keep reading for a color scheme everyone should know about.
"Red to yellow will kill a fellow, red to black is a friend of Jack." What other venomous snake gets its own mnemonic rhyme?
Several harmless snakes are often mistaken for the colorful coral snake. This ditty helps humans remember which is the non-venomous king snake and which of the two can be dangerous.
Coral snakes are petite, usually just 20 to 30 inches (50.8 to 76.2 centimeters) long as adults. They can be backyard hazards because they like to hide in piles of leaves, loose earth or even bury themselves in the ground. Their bites can be serious, and victims should get medical attention quickly.
But sometimes their bites are hard to detect, because unlike the pit vipers, they have short teeth, not long fangs. Fortunately for any human targets, this venom delivery system is sometimes less efficient than that of pit vipers.
Coral snakes may have inherited some of their tough reputation because they're related to Old World cobras.
They're found across Florida, even into the Keys, and as far north as North Carolina, west into Texas and parts of Mexico. They like to live in scrub palms, often near swamps and wetlands. Be alert, because they can also climb trees.
Copperheads can live just about anywhere, from forests and swamps to mountains and suburbs. They're medium-sized snakes, 2 to 4 feet (0.6 to 1.2 meters) long, and masters of disguise. Their copper-and-bronze color makes it easy for them to camouflage themselves in leaves, limbs or logs.
While their colors may differ, there is usually an hourglass-like banding pattern on their bodies. They're not aggressive, but an ill-fated step on them can lead to a strike.
Copperheads thrive from Mexico through most of the central United States and into New England. They're comfortable in forests and on rocky hillsides. And in what might be the most lethal roommate arrangement ever, copperheads sometimes live communally with timber rattlesnakes.
These snakes have adapted well to human developments, and are common in suburban, even city neighborhoods.
Like most snakes, there are plenty of tall tales about them. One myth claims that people can tell when copperheads are in their vicinity because they give off the scent of a cucumber. The reality is, many species of scared snakes release a musky odor from their vent, enabling possible predators to find them.
The coil of their powerful, sleek bodies, the dance of the keratin in their rattles and that forbidding forked tongue all strike fear in creatures around them, from mice to birds to humans.
When it comes to humans, rattlesnakes are a bit timid. If they sense danger, they first try to stay motionless or to blend into the background. But the consequences can be deadly if a human steps on one or tries to catch it.
These reptiles can be found in backyards, mountains, prairies, deserts, even beaches.
Rattlesnakes are pit vipers. The loreal pit, located between their nostril and eye, detects heat emitted by prey or potential predators. When the snakes strike, they can inject venom through hollow fangs. Rattlesnakes are the largest of the venomous snakes found in the United States. The Western Diamondback can be more than 7 feet (2.1 meters) long.
Even the babies are potent. Rattlesnake young have both fangs and venom at birth. And they're resilient: They can go months without eating, and can live more than 20 years.
Whether you are in your backyard or anywhere rattlesnakes reside, think before you sit down, or stick your hand into leaves or brush. You don't want to mess with a group of rattlesnakes, known as a rhumba.
For more information on dangerous animals, take a bite out of the links on the next page.
HowStuffWorks looks at the phenomenon of half and half animals.
More Great Links
- Andrews, Kimberly, and Willson, J.D. "Copperheads." Savannah River Ecology Laboratory. (Nov. 15, 2011) http://www.uga.edu/srelherp/snakes/agkcon.htm
- Arizona Game and Fish Dept. "Rattlesnake Facts." (Nov. 15, 2011) http://www.azgfd.gov/w_c/arizona-rattlesnakes.shtml
- Barnett, Parker. Wildlife biologist. Personal interview conducted Sept. 20, 2010.
- Florida Museum of Natural History "Online Guide to Florida Snakes." (Nov. 15, 2011) http://www.flmnh.ufl.edu/herpetology/fl-guide/onlineguide.htm
- Lobos, Ignacio. "Buck Rogers and the amazing death stalker scorpion." Hutchinson Cancer Research Center (Nov. 15, 2011) http://www.fhcrc.org/about/pubs/quest/articles/2007/12/scorpion.html
- Johnson, Steve. "Frequently Asked Questions About Venomous Snakes." 2007. (Nov. 15, 2011) http://ufwildlife.ifas.ufl.edu/venomous_snake_faqs.shtml
- Journal of the Federation of American Societies for Experimental Biology "Toxin Tx2-6 from the spider "Phoneutria nigriventer" improves the impaired erectile function in DOCA-Salt hypertensive rats." 2007. (Nov. 15, 2011) http://www.fasebj.org/cgi/content/meeting_abstract/21/6/A881-c
- Morgan, Randy. Curator, Invertebrates, Reptiles & Amphibians. Cincinnati Zoo and Botanical Garden. Personal interview conducted Sept. 21, 2010.
- Morgan, Randy. "Giant Tropical Bullet Ant." (Nov. 15, 2011) http://www.sasionline.org/antsfiles/pages/bullet/bulletbio.html
- National Institutes of Health Medline Plus "Snake Bites." Jan. 13, 2010. (Nov. 15, 2011) http://www.nlm.nih.gov/medlineplus/ency/article/000031.htm
- North Carolina State University "North Carolina Venomous Snakes." (Nov. 15, 2011) http://www.ces.ncsu.edu/gaston/Pests/reptiles/venomousnake.htm
- Philadelphia Zoo "Meet Our Animals." (Nov. 15, 2011) http://www.philadelphiazoo.org/zoo/meet-our-animals/reptiles/lizards-and-snakes/king-cobra.htm
- Rein, Jan Ove. "Leiurus quinquestriatus." Norwegian University of Science and Technology. (Nov. 15, 2011) http://www.ntnu.no/ub/scorpion-files/l_quinquestriatus.php
- Saint Louis Zoo. "Bullet Ant." (Nov. 15, 2011) http://www.stlzoo.org/animals/abouttheanimals/invertebrates/insects/antsbeeswasps/bulletant.htm
- San Diego Zoo. "Don't Hate Me Because I'm Venomous." 2011. (Nov. 15, 2011) http://www.sandiegozoo.org/animalbytes/t-cobra.html
- Sheils, Andrew L. "The Northern Copperhead." Pennsylvania Fish and Boat Commission. (Nov. 15, 2011) http://www.fish.state.pa.us/copprhe.htm
- Shisk-Saling, Teresa. Veterinary technician and herpetologist, Texas A&M University College of Veterinary Science. Personal interview conducted Sept. 21, 2010.
- Jackman, John A. "Black Widow Spiders." Texas A&M University. Aug. 10, 2001. (Nov. 15, 2011) http://insects.tamu.edu/extension/youth/bug/bug160.html
- Texas Agricultural Extension Service. "Spiders." 2008. (Nov. 15, 2011) http://insects.tamu.edu/extension/bulletins/l-1787.html
- University of Massachusetts-Amherst. "Snake Mythology." 2008. (Nov. 15, 2011) http://www.umass.edu/nrec/snake_pit/pages/myth.html
- U.S. Centers for Disease Control and Prevention. "Venomous Snakes." (Nov. 15, 2011) http://www.cdc.gov/niosh/topics/snakes/
- U.S. Centers for Disease Control and Prevention. "Venomous Spiders." (Nov. 15, 2011) http://www.cdc.gov/niosh/topics/spiders/
- Zurek, Ludek. "Spiders and Scorpions." Kansas State University. July 2005. (Nov. 15, 2011) http://www.ksre.ksu.edu/library/entml2/mf771.pdf