8 Survival Myths That Will Definitely Make Things Worse

You might think you know how to survive if you end up stranded in the wild, but those tips you read on the internet might just make things worse!

Some tips seem too good to be true, and they are. Others are ingrained enough to be common knowledge, except they’re wrong.

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Sources:

https://www.istockphoto.com/photo/desert-cloudscape-gm482377760-69992289
https://www.istockphoto.com/photo/snowy-empty-driving-road-in-the-winter-iceland-gm657042568-119691245

Eating snow
http://scienceline.ucsb.edu/getkey.php?key=1619
https://www.npr.org/sections/thesalt/2016/01/23/463959512/so-you-want-to-eat-snow-is-it-safe-we-asked-scientists
https://www.istockphoto.com/photo/winter-scene-thaw-gm628875450-111753311

Cactus juice
https://www.britannica.com/story/can-you-drink-water-from-a-cactus
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC148931/
https://onlinelibrary.wiley.com/doi/pdf/10.1002/jsfa.2740350410
https://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@term+@DOCNO+1202
https://www.khanacademy.org/science/biology/photosynthesis-in-plants/photorespiration–c3-c4-cam-plants/a/c3-c4-and-cam-plants-agriculture
https://www.kidney.org/atoz/content/calcium-oxalate-stone
https://commons.wikimedia.org/wiki/File:Ferocactus_wislizeni_(6541006057).jpg
https://en.wikipedia.org/wiki/File:Prickly_Pear_Closeup.jpg
https://www.istockphoto.com/photo/field-of-cactus-gm145997810-6138805

Urine and blood
http://www.slate.com/articles/news_and_politics/explainer/2008/05/the_yellow_liquid_diet.html
https://www.livescience.com/15899-drinking-blood-safe.html
https://www.hemochromatosis.org/#overview
https://www.istockphoto.com/photo/beer-with-forth-gm183243456-14730136
https://www.istockphoto.com/photo/blood-dripping-gm157509239-10684671

Moss
http://mentalfloss.com/article/56243/does-moss-really-only-grow-north-side-trees
http://scienceline.ucsb.edu/getkey.php?key=2975
http://projects.ncsu.edu/project/bio181de/Lab/plant_phylogeny/non-vascular.html
https://www.istockphoto.com/photo/strong-roots-of-old-tree-covered-with-green-moss-close-up-gm866600452-144131965
https://www.istockphoto.com/photo/the-gree-hell-mossy-roots-and-trunks-in-deep-forest-gm912425688-251189812

Alcohol
http://mentalfloss.com/article/32256/does-drinking-alcohol-really-keep-you-warm-when-its-cold-out
https://www.ncbi.nlm.nih.gov/pubmed/2318781
https://www.princeton.edu/~oa/safety/hypocold.shtml
https://www.istockphoto.com/photo/close-up-view-of-the-bottle-in-ice-gm133897014-18274727
https://www.istockphoto.com/photo/young-woman-drinking-a-tea-on-the-city-gm628664428-111676911

Frostbite
https://emedicine.medscape.com/article/926249-overview#a3
https://www.mayoclinic.org/diseases-conditions/hypothermia/diagnosis-treatment/drc-20352688
https://www.istockphoto.com/photo/man-with-a-tan-beanie-and-red-scarf-trying-to-warm-up-gm142527503-17874723

Snakebite
http://www.nejm.org/doi/full/10.1056/NEJMra013477
https://www.omicsonline.org/open-access/pathophysiological-and-pharmacological-effects-of-snake-venom-components-molecular-targets-2161-0495.1000-190.php?aid=25709
http://www.umich.edu/~elements/fogler&gurmen/html/web_mod/cobra/avenom.htm
https://www.istockphoto.com/photo/venomous-snake-bites-mans-finger-gm939901378-256963981
https://www.istockphoto.com/photo/isolated-diamondback-rattlesnake-gm91032724-5881298

Jellyfish
https://www.britannica.com/science/nematocyst#ref1013437
http://www.mdpi.com/2072-6651/9/3/105/htm?xid=PS_smithsonian
https://www.smithsonianmag.com/travel/how-fix-jellyfish-sting-180963582/
https://www.smithsonianmag.com/science-nature/whats-behind-that-jellyfish-sting-2844876/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4728541/
https://www.nytimes.com/2007/08/14/health/14real.html
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3773479/
https://en.wikipedia.org/wiki/File:Moon_jellyfish_at_Gota_Sagher.JPG
https://www.istockphoto.com/photo/stingers-gm172300393-3544362

Thumbnail:
https://www.istockphoto.com/photo/caveman-gm157533887-11308958

Take Two Leeches and Call Me in the Morning | Deep Look

(FYI – This episode is a *bit* more bloody that usual – especially a little after the 2-minute mark. Just letting you know in case flesh wounds aren’t your thing)

The same blood-sucking leeches feared by hikers and swimmers are making a comeback… in hospitals. Once used for questionable treatments, leeches now help doctors complete complex surgeries to reattach severed body parts.

SUBSCRIBE to Deep Look! http://goo.gl/8NwXqt

DEEP LOOK: a new ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small.

Leeches get a bad rap—but they might not deserve it. Yes, they’re creepy crawly blood-suckers. And they can instill an almost primal sense of disgust and revulsion. Humphrey Bogart’s character in the 1951 film The African Queen even went so far as to call them “filthy little devils.”

But the humble leech is making a comeback. Contrary to the typical, derogatory definition of a human “leech,” this critter is increasingly playing a key role as a sidekick for scientists and doctors, simply by being its bloodthirsty self.

Distant cousins of the earthworm, most leech species are parasites that feed on the blood of animals and humans alike. They are often found in freshwater and navigate either by swimming or by inching themselves along, using two suckers—one at each end of their body—to anchor themselves.

Upon reaching an unsuspecting host, a leech will surreptitiously attach itself and begin to feed. It uses a triangular set of three teeth to cut in, and secretes a suite of chemicals to thin the blood and numb the skin so its presence goes undetected.

—+ Read the entire article on KQED Science: https://www.kqed.org/science/1921659/take-two-leeches-and-call-me-in-the-morning

—+ For more information:
David Weisblat at UC Berkeley studies leeches development and evolution
https://mcb.berkeley.edu/labs/weisblat/research.html

Biologists recently reported that leeches in that region can provide a valuable snapshot of which animals are present in a particular area
https://www.tandfonline.com/doi/abs/10.1080/14772000.2018.1433729?journalCode=tsab20&

—+ More Great Deep Look episodes:

Why the Male Black Widow is a Real Home Wrecker | Deep Look
https://www.youtube.com/watch?v=NpJNeGqExrc

For Pacific Mole Crabs It’s Dig or Die | Deep Look
https://www.youtube.com/watch?v=tfoYD8pAsMw

Praying Mantis Love is Waaay Weirder Than You Think | Deep Look
https://www.youtube.com/watch?v=NHf47gI8w04&t=83s

—+ See some great videos and documentaries from the PBS Digital Studios! Above the Noise:

Cow Burps Are Warming the Planet | Reactions
https://www.youtube.com/watch?v=MnRFUSGz_ZM

What a Dinosaur Looks Like Under a Microscope | Eons
https://www.youtube.com/watch?v=4rvgiDXc12k
Hawking Radiation | Space Time
https://www.youtube.com/watch?v=qPKj0YnKANw

—+ Follow KQED Science:
KQED Science: http://www.kqed.org/science
Tumblr: http://kqedscience.tumblr.com
Twitter: https://www.twitter.com/kqedscience

—+ About KQED KQED, an NPR and PBS affiliate in San Francisco, CA, serves Northern California and beyond with a public-supported alternative to commercial TV, Radio and web media.

Funding for Deep Look is provided in part by PBS Digital Studios. Deep Look is a project of KQED Science, which is supported by the S. D. Bechtel, Jr. Foundation, the Dirk and Charlene Kabcenell Foundation, the Vadasz Family Foundation, the Gordon and Betty Moore Foundation, the Fuhs Family Foundation Fund and the members of KQED.

How Ticks Dig In With a Mouth Full of Hooks | Deep Look

Why can’t you just flick a tick? Because it attaches to you with a mouth covered in hooks, while it fattens up on your blood. For days. But don’t worry – there *is* a way to pull it out.

SUBSCRIBE to Deep Look! http://goo.gl/8NwXqt

DEEP LOOK: a new ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Explore big scientific mysteries by going incredibly small.

Spring is here. Unfortunately for hikers and picnickers out enjoying the warmer weather, the new season is prime time for ticks, which can transmit bacteria that cause Lyme disease.

How they latch on – and stay on – is a feat of engineering that scientists have been piecing together. Once you know how a tick’s mouth works, you understand why it’s impossible to simply flick a tick.

The key to their success is a menacing mouth covered in hooks that they use to get under the surface of our skin and attach themselves for several days while they fatten up on our blood.

“Ticks have a lovely, evolved mouth part for doing exactly what they need to do, which is extended feeding,” said Kerry Padgett, supervising public health biologist at the California Department of Public Health in Richmond. “They’re not like a mosquito that can just put their mouth parts in and out nicely, like a hypodermic needle.”

Instead, a tick digs in using two sets of hooks. Each set looks like a hand with three hooked fingers. The hooks dig in and wriggle into the skin. Then these “hands” bend in unison to perform approximately half-a-dozen breaststrokes that pull skin out of the way so the tick can push in a long stubby part called the hypostome.

“It’s almost like swimming into the skin,” said Dania Richter, a biologist at the Technische Universität in Braunschweig, Germany, who has studied the mechanism closely. “By bending the hooks it’s engaging the skin. It’s pulling the skin when it retracts.”

The bottom of their long hypostome is also covered in rows of hooks that give it the look of a chainsaw. Those hooks act like mini-harpoons, anchoring the tick to us for the long haul.

“They’re teeth that are backwards facing, similar to one of those gates you would drive over but you’re not allowed to back up or else you’d puncture your tires,” said Padgett.

— How to remove a tick.
Kerry Padgett, at the California Department of Public Health, recommends grabbing the tick close to the skin using a pair of fine tweezers and simply pulling straight up.

“No twisting or jerking,” she said. “Use a smooth motion pulling up.”

Padgett warned against using other strategies.

“Don’t use Vaseline or try to burn the tick or use a cotton swab soaked in soft soap or any of these other techniques that might take a little longer or might not work at all,” she said. “You really want to remove the tick as soon as possible.”

— What happens if the mouth of a tick breaks off in your skin?
Don’t worry if the tick’s mouth parts stay behind when you pull.

“The mouth parts are not going to transmit disease to people,” said Padgett.

If the mouth stayed behind in your skin, it will eventually work its way out, sort of like a splinter does, she said. Clean the bite area with soap and water and apply antibiotic ointment.

—+ Read the entire article on KQED Science: https://www.kqed.org/science/1920972/how-ticks-dig-in-with-a-mouth-full-of-hooks

—+ For more information:
Centers for Disease Control information on Lyme disease:
https://www.cdc.gov/lyme/

Mosquito & Vector Control District for San Mateo County, California:
https://www.smcmvcd.org/ticks

—+ More Great Deep Look episodes:

How Mosquitoes Use Six Needles to Suck Your Blood
https://www.youtube.com/watch?v=rD8SmacBUcU

So … Sometimes Fireflies Eat Other Fireflies
https://www.youtube.com/watch?v=oWdCMFvgFbo

Meet the Dust Mites, Tiny Roommates That Feast On Your Skin
https://www.youtube.com/watch?v=ACrLMtPyRM0

—+ See some great videos and documentaries from the PBS Digital Studios!

Above the Noise: Are Energy Drinks Really that Bad?
https://www.youtube.com/watch?v=5l0cjsZS-eM

It’s Okay To Be Smart: Inside an ICE CAVE! – Nature’s Most Beautiful Blue
https://www.youtube.com/watch?v=P7LKm9jtm8I

—+ Follow KQED Science:
KQED Science: http://www.kqed.org/science
Tumblr: http://kqedscience.tumblr.com
Twitter: https://www.twitter.com/kqedscience

—+ About KQED
KQED, an NPR and PBS affiliate in San Francisco, CA, serves Northern California and beyond with a public-supported alternative to commercial TV, Radio and web media.

Funding for Deep Look is provided in part by PBS Digital Studios. Deep Look is a project of KQED Science, which is supported by the S. D. Bechtel, Jr. Foundation, the Dirk and Charlene Kabcenell Foundation, the Vadasz Family Foundation, the Gordon and Betty Moore Foundation, the Fuhs Family Foundation Fund and the members of KQED.

So … Sometimes Fireflies Eat Other Fireflies | Deep Look

Most firefly flashes are pure romance, a sexy form of skywriting. But one variety copies the mating signals of others to lure them to their demise.

SUBSCRIBE to Deep Look! http://goo.gl/8NwXqt

DEEP LOOK: a new ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Get a new perspective on our place in the universe and meet extraordinary new friends. Explore big scientific mysteries by going incredibly small.

Most of the blinking signals that fireflies send out are intended to attract mates. But researchers are finding out that in some cases, these romantic overtures are not all wine and roses.

Females of one firefly group, the genus Photuris, have learned to copy other fireflies’ flashes to attract the males of those species. When one arrives, she pounces, first sucking his blood, then devouring his insides.

These “femme fatale” fireflies live throughout the Eastern U.S alongside the fireflies they target. They can develop widely varying light shows to target whatever species are in the area.

The predatory habits of Photuris are just one example of how much individual firefly signals can differ from one another.

The male Common Eastern Firefly, for example, is known for his fish hook-shaped aerial maneuver, which he repeats at six-second intervals. That characteristic move has earned the species the nickname “Big Dipper.”

The male Big Dipper hopes this bit of skywriting will get him noticed by females hiding in the grass. If the female likes what she sees, her reply comes as a single pulse from her smaller, heart-shaped lantern. That’s his invitation to land and mate.

Most firefly interactions follow the same pattern, with roving males advertising themselves to concealed females. Within a species, the back-and-forth signals are so reliable that it’s easy to attract the male fireflies with even a simple decoy.

Firefly light is biochemical. But fireflies like the Big Dippers do much more with chemistry than just make light. They can mix together an array of other compounds, including invisible pheromones for mating, and others called lucibufagins (“loosa-BOOF-ajins”) that ward off predators like spiders and birds.

At some point, the Photuris “femme fatale” fireflies lost the ability to make their own lucibufagins. So instead of chemistry, these bigger, stronger fireflies became adept at imitation, and evolved to turn into insect vampires to take these valuable compounds from other fireflies to boost their own defenses.

And it works. In experiments, predators avoided Photuris fireflies that had recently preyed on other fireflies.

— Where do fireflies live?

There are fireflies worldwide, but in the U.S., you’ll find them in the Midwest and Eastern U.S. There are a few species in the West, including the California Pink Glow-worm.

— Why do fireflies flash?

Mostly, it’s to attract mates. One sex, usually the male, uses a more elaborate flash pattern to get the attention of the opposite sex. Then the female signals her interest with a simpler flash.

— Why do fireflies glow after they die?

The chemicals in the firefly that make light, luciferin and luciferase, remain viable after it dies, and the reaction that creates the light thrives on oxygen, which is of course plentiful in the air.

—+ Read the entire article on KQED Science:

https://ww2.kqed.org/2018/02/27/so-sometimes-fireflies-eat-other-fireflies

—+ For more information:

Join Fireflyers International: https://fireflyersinternational.net/

—+ More Great Deep Look episodes:

Everything You Never Wanted to Know About Snail Sex
https://youtu.be/UOcLaI44TXA

Why the Male Black Widow is a Real Home Wrecker
https://youtu.be/NpJNeGqExrc

—+ See some great videos and documentaries from the PBS Digital Studios!

PBS Eons: When Giant Fungi Ruled
https://www.youtube.com/watch?v=-G64DagHuOg

Origin Of Everything: Why Do We Eat Artificial Flavors?
https://www.youtube.com/watch?v=iNaJ31EV13U

—+ Follow KQED Science:

KQED Science: http://www.kqed.org/science
Tumblr: http://kqedscience.tumblr.com
Twitter: https://www.twitter.com/kqedscience

—+ About KQED

KQED, an NPR and PBS affiliate in San Francisco, CA, serves Northern California and beyond with a public-supported alternative to commercial TV, Radio and web media.

Funding for Deep Look is provided in part by PBS Digital Studios. Deep Look is a project of KQED Science, which is supported by the S. D. Bechtel, Jr. Foundation, the Dirk and Charlene Kabcenell Foundation, the Vadasz Family Foundation, the Gordon and Betty Moore Foundation, the Fuhs Family Foundation Fund and the members of KQED.

Why Are Mosquitoes Attracted To Me?!

Mosquitoes are attracted to me and it’s likely due to my genes.
This video is sponsored by 23andMe https://23andme.com/veritasium
Huge thanks to Prof. Immo Hansen and team: http://ve42.co/hansen

References:
Genome Wide Association Study for self-reported mosquito attractiveness:
http://ve42.co/MossieGWAS

The twin study showing correlated attractiveness is stronger for identical twins:
http://ve42.co/MossieTwins

Some things we know make mosquitoes more attracted to you:
Exercising, higher metabolism, higher body temperature, more body odor, being pregnant, type O blood, infrequent bathing, lactic acid, ammonia, acetone.

There are a number of folk remedies people believe protect them from mosquito bites like drinking alcohol, eating garlic, or taking vitamin B. These do not appear to provide any benefit in lab studies and in fact drinking alcohol is associated with increased mosquito activity because it causes blood vessels near the surface of the skin to dilate.

And apparently some of your attractiveness to mosquitos is simply genetic. This may be mediated through your immune system, which is what a lot of the genes identified were associated with.

Molecular models are microSnatoms: http://snatoms.com

Filming in New Mexico by Raquel Nuno
Animations by Jacqui Robertson

The opinions and conclusions drawn in this video are those of Veritasium and not 23andMe.

Why the Male Black Widow is a Real Home Wrecker | Deep Look

Sure, the female black widow has a terrible reputation. But who’s the real victim here? Her male counterpart is a total jerk — and might just be getting what he deserves.

SUBSCRIBE to Deep Look! http://goo.gl/8NwXqt

DEEP LOOK: a new ultra-HD (4K) short video series created by KQED San Francisco and presented by PBS Digital Studios. See the unseen at the very edge of our visible world. Get a new perspective on our place in the universe and meet extraordinary new friends. Explore big scientific mysteries by going incredibly small.

We’ve all heard the stories. She mates and then kills. Her venom is 15 times stronger than a rattlesnake’s. One bite could kill you. With a shiny black color and a glaring red hourglass stomach, she has long inspired fear and awe.

But most species of widow spider (there are 31), including the western black widow found in the U.S., don’t kill their mates at all. Only two widow spider species always eat their mate, the Australian redback and the brown widow, an invasive species in California.

And the male seems to be asking for it. In both of these species, he offers himself to her, somersaulting into her mouth after copulation.

He may even deserve it. During peak mating season, thousands of males will prowl around looking for females. Females set up their webs, stay put and wait.

Once the male arrives at her silken abode, he starts to wreck it, systematically disassembling her web one strand at a time. In a process scientists call web reduction, he bunches it into a little ball and wraps it up with his own silk.

Then, while mating, he will wrap her in fine strands that researchers refer to as the bridal veil. He drapes his silk over her legs, where her smell receptors are most concentrated.

After all of that, he is most likely to crawl away, alive and unscathed.

— Why does the black widow spider eat her mate?

No one really knows, but scientists assume his body supplies her with nutrition for laying eggs. Sometimes she eats him by accident, not recognizing him as a mate.

— How harmful are black widows to people?

We couldn’t find a documented case of a human death from a black widow spider in the U.S., but a bite will make you sick with extreme flu-like symptoms. Luckily, black widows aren’t aggressive to people.

— Why do black widows have a red hourglass?

It’s a warning sign, a phenomenon common in nature that scientists call aposematicism, which is the use of color to ward off enemies.

—+ Read the entire article on KQED Science:

https://ww2.kqed.org/science/2018/01/09/why-the-male-black-widow-is-a-real-home-wrecker

—+ For more information:

Black widow researcher Catherine Scott’s website: http://spiderbytes.org/

—+ More Great Deep Look episodes:

Why Is The Very Hungry Caterpillar So Dang Hungry?
https://www.youtube.com/watch?v=el_lPd2oFV4

Everything You Never Wanted to Know About Snail Sex
https://www.youtube.com/watch?v=UOcLaI44TXA

—+ See some great videos and documentaries from the PBS Digital Studios!

Origin of Everything: Why Does Santa Wear Red?
https://www.youtube.com/watch?v=fajNM5OPVnA

PBS Eons: ‘Living Fossils’ Aren’t Really a Thing
https://www.youtube.com/watch?v=mPvZj2KcjAY

—+ Follow KQED Science:

KQED Science: http://www.kqed.org/science
Tumblr: http://kqedscience.tumblr.com
Twitter: https://www.twitter.com/kqedscience

—+ About KQED

KQED, an NPR and PBS affiliate based in San Francisco, serves the people of Northern California and beyond with a public-supported alternative to commercial media. Home to one of the most listened-to public radio station in the nation, one of the highest-rated public television services and an award-winning education program, KQED is also a leader and innovator in interactive media and technology, taking people of all ages on journeys of exploration — exposing them to new people, places and ideas.

Funding for Deep Look is provided in part by PBS Digital Studios and the John S. and James L. Knight Foundation. Deep Look is a project of KQED Science, which is supported by HopeLab, The David B. Gold Foundation; S. D. Bechtel, Jr. Foundation; The Dirk and Charlene Kabcenell Foundation; The Vadasz Family Foundation; Smart Family Foundation and the members of KQED.