The Reason Why Stop Signs Are Red

Roman_Gorielov, iStock/Getty Images Plus
Roman_Gorielov, iStock/Getty Images Plus

Why is red the standard color for stop signs? The short answer is this: because the representatives of the First National Conference on Street and Highway Safety in 1924 decided so.

Though stop signs were still a relatively new idea in the United States back in the 1920s—Detroit erected the first one around 1915, Jalopnik reports—the “red means ‘stop’” custom dates back to 1841, when Henry Booth of the Liverpool and Manchester Railway suggested using red to indicate danger on railroads. London then adopted the color for its regular traffic lights in 1868, and the United States eventually followed suit.

The First National Conference on Street and Highway Safety, called by then-Secretary of Commerce Herbert Hoover in 1924, aimed to standardize the color coding of road signage. It established that for all “signs and signals, both luminous and nonluminous,” red should indicate “stop,” green should indicate “proceed,” and yellow should indicate “caution,” according to the report released after the conference [PDF]. It was also decided that distance and direction signs should be black and white.

That all probably sounds familiar if you’ve ever seen a street before, but implementing the mandate for red stop signs posed immediate issues. A red material that wouldn’t fade over time just didn’t exist in 1924, Gene Hawkins, a professor of civil engineering at Texas A&M University, told The New York Times in 2011. So the writers of the 1935 Manual on Uniform Traffic Control Devices chose the next best thing: yellow. The manual also specified that every sign should be octagonal, another idea from the 1920s.

California was first to figure out that porcelain enamel would resist fading and erect red stop signs across the state, a practice noticed and addressed in the 1954 revision [PDF] to the Manual on Uniform Traffic Control Devices. Now that red was more logistically feasible, the committee in charge of updating the manual decided there should be no more yellow stop signs.

We don’t know exactly why Henry Booth and other early industrialists felt that red aptly signaled “stop.” Maybe they thought it was harder to overlook than blue or green, which natural surroundings like water and foliage might easily camouflage. Maybe they felt red, like fire or blood, just went along well with danger.

There may also be a deeper reason. When, as part of a 2011 study, red-, blue-, and green-clad human experimenters offered apple slices to individual monkeys in a free-range facility, the monkeys seemed to have an aversion to taking slices left by the experimenter wearing red. Perhaps our association of danger with the color red has a psychological basis we don’t fully understand yet.

[h/t Jalopnik]

10 Rad Gifts for Hikers

Greg Rosenke/Unsplash
Greg Rosenke/Unsplash

The popularity of bird-watching, camping, and hiking has skyrocketed this year. Whether your gift recipients are weekend warriors or seasoned dirtbags, they'll appreciate these tools and gear for getting most out of their hiking experience.

1. Stanley Nesting Two-Cup Cookset; $14

Amazon

Stanley’s compact and lightweight cookset includes a 20-ounce stainless steel pot with a locking handle, a vented lid, and two insulated 10-ounce tumblers. It’s the perfect size for brewing hot coffee, rehydrating soup, or boiling water while out on the trail with a buddy. And as some hardcore backpackers note in their Amazon reviews, your favorite hiker can take the tumblers out and stuff the pot with a camp stove, matches, and other necessities to make good use of space in their pack.

Buy it: Amazon

2. Osprey Sirrus and Stratos 24-Liter Hiking Packs; $140

Amazon

Osprey’s packs are designed with trail-tested details to maximize comfort and ease of use. The Sirrus pack (pictured) is sized for women, while the Stratos fits men’s proportions. Both include an internal sleeve for a hydration reservoir, exterior mesh and hipbelt pockets, an attachment for carrying trekking poles, and a built-in rain cover.

Buy them: Amazon, Amazon

3. Yeti Rambler 18-Ounce Bottle; $48

Amazon

Nothing beats ice-cold water after a summer hike or a sip of hot tea during a winter walk. The Yeti Rambler can serve up both: Beverages can stay hot or cold for hours thanks to its insulated construction, and its steel body (in a variety of colors) is basically indestructible. It will add weight to your hiker's pack, though—for a lighter-weight, non-insulated option, the tried-and-true Camelbak Chute water bottle is incredibly sturdy and leakproof.

Buy it: Amazon

4. Mappinners Greatest 100 Hikes of the National Parks Scratch-Off Poster; $30

Amazon

The perfect gift for park baggers in your life (or yourself), this 16-inch-by-20-inch poster features epic hikes like Angel’s Landing in Zion National Park and Half Dome in Yosemite National Park. Once the hike is complete, you can scratch off the gold foil to reveal an illustration of the park.

Buy it: Amazon

5. National Geographic Adventure Edition Road Atlas; $19

Amazon

Hikers can use this brand-new, updated road atlas to plan their next adventure. In addition to comprehensive maps of all 50 states, Puerto Rico, Canada, and Mexico, they'll get National Geographic’s top 100 outdoor destinations, useful details about the most popular national parks, and points on the maps noting off-the-beaten-path places to explore.  

Buy it: Amazon

6. Adventure Medical Kits Hiker First-Aid Kit; $25

Amazon

This handy 67-piece kit is stuffed with all the things you hope your hiker will never need in the wilderness. Not only does it contain supplies for pain, cuts and scrapes, burns, and blisters (every hiker’s nemesis!), the items are organized clearly in the bag to make it easy to find tweezers or an alcohol wipe in an emergency.

Buy it: Amazon

7. Hiker Hunger Ultralight Trekking Poles; $70

Amazon

Trekking poles will help increase your hiker's balance and stability and reduce strain on their lower body by distributing it to their arms and shoulders. This pair is made of carbon fiber, a super-strong and lightweight material. From the sweat-absorbing cork handles to the selection of pole tips for different terrain, these poles answer every need on the trail. 

Buy it: Amazon

8. Leatherman Signal Camping Multitool; $120

Amazon

What can’t this multitool do? This gadget contains 19 hiking-friendly tools in a 4.5-inch package, including pliers, screwdrivers, bottle opener, saw, knife, hammer, wire cutter, and even an emergency whistle.

Buy it: Amazon

9. RAVPower Power Bank; $24

Amazon

Don’t let your hiker get caught off the grid with a dead phone. They can charge RAVPower’s compact power bank before they head out on the trail, and then use it to quickly juice up a phone or tablet when the batteries get low. Its 3-inch-by-5-inch profile won’t take up much room in a pack or purse.

Buy it: Amazon

10. Pack of Four Indestructible Field Books; $14

Amazon

Neither rain, nor snow, nor hail will be a match for these waterproof, tearproof 3.5-inch-by-5.5-inch notebooks. Your hiker can stick one in their pocket along with a regular pen or pencil to record details of their hike or brainstorm their next viral Tweet.

Buy it: Amazon

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The Reason Stone Crabs Are So Expensive

Thomas Hawk, Flickr // CC BY-NC 2.0
Thomas Hawk, Flickr // CC BY-NC 2.0

Many people associate lobster with fine dining, but the stone crab may be the true king of fancy shellfish. Per pound, the crab is the most expensive seafood consumed in the United States. The crustacean is highly sought after for its delicate, succulent taste, but that's not the only reason for its high price tag. The cost of stone crabs comes from the way the creature is harvested.

To prevent their population from being wiped out, stone crab fishing is strictly regulated. In Florida, where 98 percent of all stone crabs sold in the country originate, the crabs can only be harvested from October 15 through May 1. That's why stone crab season lasts half the year at markets and restaurants.

Stone crab harvesting isn't as simple as hauling a box of live crabs to shore. Fishermen are only allowed to collect one claw from each crab they catch. The claw must be at least 2.75 inches long, and it can't belong to an egg-bearing female.

Once the claw is broken off, the live crab is thrown back into the ocean, where it will have a chance to continue mating and reproducing. Stone crabs can survive with one claw, and it takes them about a year to regrow the lost appendage. That means there's a good chance the owner of the stone crab claw you ordered is still crawling through the ocean when your dinner arrives.

Due to these sustainability practices, one pound of stone crab takes more time and effort to harvest than most other crustaceans. The crab can sell anywhere from $30 to $60 per pound depending on the claw size. And thanks to high demand from seafood lovers, that price likely won't go down anytime soon.