Parasites are creatures that exploit another creature — the host — for food, shelter or protection. Sometimes parasites are fairly innocuous. For example, you probably have some intestinal protozoa flailing around in your guts right now that are feeding off of your breakfast, but those little guys most likely aren't going to make you sick.
Then there's the Loa loa worm, which is native to wet areas of West Africa. Spread by fly bites, the worm courses beneath your skin and can wiggle its way into your eyes. If your friends peer closely enough they'll actually be able to see your little parasite writhing around, and you'll be able to feel it, too. Horrifying? Yes. But the Loa loa isn't alone.
All told, there may be around 100 or so parasites built specifically to latch onto humans. That doesn't really capture the whole story, though. Some researchers estimate that most creatures on Earth probably exhibit parasitic behavior at some point in their lifecycles, and that this kind of activity is actually necessary to keep ecosystems working properly. Dog eat dog world, indeed.
If parasitism is an integral part of life on Earth, what exactly does that say about our lives on this planet? Earth may be our life raft in an ocean of universal vastness and uncertainty, but it is far from a benign and friendly place. From volcanoes to venomous snakes to jarring earthquakes, our home world is a place loaded with danger in every nook and cranny. Be safe out there — our Earth is trying to kill you.
Author's Note: 10 Ways the Earth Is Trying to Kill You
I distinctly remember the first time I was sure I was going to die. I was whitewater kayaking on a river in Montana. It was late summer, and the river level was low, slow and docile compared to its springtime fury. Yet it only took one mistake to remind me that Mother Nature — not me or my paddle or even my life jacket — was in charge of the situation. I bumped a boulder hard, flipped and then was sucked deep underwater for what seemed like an eternity. The water was so overwhelmingly powerful that I instinctively knew that I had no way to fight back, and that without some twist of good fortune I was going to drown. Luckily, a swirl in the current swept me back up toward the surface ... and a second chance. Our planet might offer all sorts of beauty and fun, but it also serves of regular doses of pain and suffering, too. Sometimes we're just barely lucky enough to survive.
More Great Links
- BBC News. "1986: Hundreds Gassed in Cameroon Lake Disaster." (June 19, 2015) http://news.bbc.co.uk/onthisday/hi/dates/stories/august/21/newsid_3380000/3380803.stm
- Ball, Jessica. "Volcanic Hazards." Geology. (June 19, 2015) http://geology.com/volcanoes/volcanic-hazards/
- Cain, Fraser. "Volcano Dangers." Universe Today. April 22, 2009. (June 19, 2015) http://www.universetoday.com/29667/volcano-dangers/
- Choi, Charles Q. "The 10 Most Diabolical and Disgusting Parasites." Live Science. March 2, 2011. (June 19, 2015) http://www.livescience.com/13040-10-disgusting-parasites-zombie-ants-toxoplasma.html
- Engber, Daniel. "How Does Heat Kill You?" Slate. Aug. 4, 2006. (June 19, 2015) http://www.slate.com/articles/news_and_politics/explainer/2006/08/how_does_heat_kill_you.html
- ESRI. "Top 10 Most Damaging U.S. Hurricanes of All Time." (June 19, 2015) http://storymaps.esri.com/stories/2012/top-ten-hurricanes/
- Fecht, Sarah. "Why Japan's Massive Earthquakes Surprised Scientists." Popular Mechanics. March 11, 2011. (June 19, 2015) http://www.popularmechanics.com/science/environment/a11822/why-japans-massive-earthquake-surprised-scientists-5382984/
- Fink, Micah. "Degassing Lake Nyos." PBS. (June 19, 2015) http://www.pbs.org/wnet/savageplanet/01volcano/01/indexmid.html
- Gannon, Megan. "Why Heatwaves Can Mean High Death Tolls." Live Science. Aug. 1, 2012. (June 19, 2015) http://www.livescience.com/22050-heat-waves-high-death-tolls.html
- History.com Staff. "Black Death." 2010. (June 19, 2015) http://www.history.com/topics/black-death
- HurricaneScience. "1970 - The Great Bhola Cyclone." (June 19, 2015) http://www.hurricanescience.org/history/storms/1970s/greatbhola/
- Kuhne, Michael. "Ten Years Later: Remembering the Deadliest Tsunami in Recorded History." Accuweather. Dec. 26, 2014. (June 19, 2015) http://www.accuweather.com/en/weather-news/10-year-anniversary-tsunami-indian-ocean/39122355
- Live Science. "History's Biggest Tsunamis." March 11, 2011. (June 19, 2015) http://www.livescience.com/13176-history-biggest-tsunamis-earthquakes.html
- National Geographic News. "Tsunamis: Facts About Killer Waves." Jan. 14, 2005. (June 19, 2015) http://news.nationalgeographic.com/news/2004/12/1228_041228_tsunami.html
- Oregon State University. "Deadliest Eruption." Volcano World. (June 19, 2015) http://volcano.oregonstate.edu/deadliest-eruption
- Howard, Brian Clark. "'Fire Tornado' in Viral Video Explained." National Geographic. March 27, 2014. (June 19, 2015) http://news.nationalgeographic.com/news/2014/03/140326-fire-tornado-controlled-burn-dust-devils-science/
- McLeod, Jaime. "Can It Really Rain Cats and Dogs?" Farmer's Almanac. Oct. 25, 2010. (June 19, 2015) http://farmersalmanac.com/weather/2010/10/25/can-it-really-rain-cats-and-dogs/
- NBC News. "The Top 10 Deadliest Earthquakes in History." 2013. (June 19, 2015) http://www.nbcnews.com/id/42029974/ns/world_news-asia_pacific/t/top-deadliest-earthquakes-history/
- Nobel, Justin. "When Animals Fall from the Sky." Modern Farmer. March 18, 2014. (June 19, 2015) http://modernfarmer.com/2014/03/things-fall-sky/
- Nuwer, Rachel. "'Parasitism is the Most Popular Lifestyle on Earth.'" New Scientist. July 29, 2013. (June 19, 2015) http://www.newscientist.com/article/mg21929270.300-parasitism-is-the-most-popular-lifestyle-on-earth.html
- Pruitt, Sarah. "Medieval 'Black Death' Was Airborne, Scientists Say." History. April 1, 2014. (June 19, 2015) http://www.history.com/news/medieval-black-death-was-airborne-scientists-say
- Robert Wood Johnson Foundation. "The Five Deadliest Outbreaks and Pandemics in History." Dec. 16, 2013. (June 19, 2015) http://www.rwjf.org/en/culture-of-health/2013/12/the_five_deadliesto.html
- Rose, Steve. "Firenado: A Spectacular Mix of Fire and a Tornado." The Guardian. May 11, 2014. (June 19, 2015) http://www.theguardian.com/world/shortcuts/2014/may/11/firenado-fire-tornado-firenadoes
- Wilkins, Alasdair. "When It Rains Animals: The Science of True Weather Weirdness." Io9. March 21, 2012. (June 19, 2015) http://io9.com/5895116/the-mystery-of-raining-animals-and-other-impossible-but-real-weather-weirdness
- Zielinski, Sarah. "What Makes a Volcano Dangerous? People." Smithsonian Magazine. July 22, 2014. (June 19, 2015) http://www.smithsonianmag.com/science-nature/what-makes-volcano-dangerous-people-180952099/?no-ist
Thanks in part to strict building codes, damage from Anchorage, Alaska's November 7.0 earthquake was relatively minimal. HowStuffWorks looks at how.