How Many of these 25 Brain Teasers Can You Solve?

iStock
iStock

1. THE POLE-CLIMBING SLOTH

A slippery sloth climbs six feet up a utility pole during the day, then slides back down five feet during the night. If the pole is 30 feet high and the sloth starts from the ground (zero feet), how many days does it take the sloth to reach the top of the pole?

Answer: 25 days. The math here boils down to a net gain of one foot per day, along with a threshold (24 feet at the beginning of a day) that must be attained so that the sloth can get to the 30-foot mark within a given day. After 24 days and 24 nights, the sloth is 24 feet up. On that 25th day, the sloth scrambles up six feet, attaining the 30-foot top of the pole. Left to the reader is a motivation for the sloth to attempt this feat in the first place. Perhaps there is something tasty atop the pole?

(Adapted from a brain teaser by Carl Proujan.)

2. THE PIRATE RIDDLE

A group of five pirates have to divide up their bounty of 100 coins, as described in the video below. The captain gets to propose a distribution plan, and all five of the pirates vote "yarr" or "nay" on the proposal. If a majority votes "nay," the captain walks the plank. The pirates are arranged in order, and vote in that order: the captain, Bart, Charlotte, Daniel, and Eliza. If a majority vote "nay" and the captain walks the plank, the captain's hat goes to Bart, and the process repeats down the line, with a series of proposals, votes, and other acceptance or plank-walking.

How can the captain stay alive, while getting as much gold as possible? (In other words, what is the optimal amount of gold the captain should offer to each pirate, himself included, in his proposal?) Watch the video below for all the rules.

Answer: The captain should propose that he keep 98 coins, distribute one coin each to Charlotte and Eliza, and offer nothing to Bart and Daniel. Bart and Daniel will vote nay, but Charlotte and Eliza have done the math and vote yarr, knowing that the alternative would get them even less booty.

3. THE HIKER'S DILEMMA

A hiker comes across an intersection where three roads cross. He looks for the sign indicating the direction to his destination city. He finds that the pole carrying three city names and arrows pointing to them has fallen. He picks it up, considers it, and pops it back into place, pointing out the correct direction for his destination. How did he do it?

Answer: He knew which city he had just come from. He pointed that arrow back toward his origin point, which oriented the signs properly for his destination and a third city.

(Adapted from a brain teaser by Jan Weaver.)

4. THE PASSCODE RIDDLE

In the video below, the rules of this riddle are laid out. Here's a snippet: Three team members are imprisoned, and one is allowed the opportunity to escape by facing a challenge. Given perfect logical skills, how can the remaining two team members listen in on what the chosen team member does, and infer the three-digit passcode to get them out?

Answer: The passcode is 2-2-9, for hallway 13.

5. COUNTING BILLS

I had a wad of money in my pocket. I gave half away and of what remained, I spent half. Then, I lost five dollars. That left me with just five bucks. How much money did I start with?

Answer: 40 dollars.

(Adapted from a brain teaser by Charles Booth-Jones.)

6. THE AIRPLANE FUEL RIDDLE

Professor Fukanō plans to circumnavigate the world in his new airplane, as shown in the video below. But the plane's fuel tank doesn't hold enough for the trip—in fact, it holds only enough for half the trip. Fukanō has two identical support planes, piloted by his assistants Fugori and Orokana. The planes can transfer fuel in midair, and they must all take off from and land at the same airport on the equator.

How can the three cooperate and share fuel so that Fukanō gets all the way around the world and nobody crashes? (Check the video for more details.)

Answer: All three planes took off at noon, flying west, fully loaded with fuel (180 kiloliters each). At 12:45, each plane has 135 kl remaining. Orokana gives 45 kl to each of the other two planes, then heads back to the airport. At 14:15, Fugori gives another 45 kl to the professor, then heads back to the airport. At 15:00, Orokana flies east, effectively flying toward the professor around the globe. At precisely 16:30, Orokana gives him 45 kl and flips around, now flying alongside the professor. Meanwhile, Fugori takes off and heads for the pair. He meets them at 17:15 and transfers 45 kl to each plane. All three planes now have 45 kl and make it back to the airport.

7. THE HAYSTACK PROBLEM

A farmer has a field with six haystacks in one corner, a third as many in another corner, twice as many in a third corner, and five in the fourth corner. While piling the hay together in the center of the field, the farmer let one of the stacks get scattered all over the field by the wind. How many haystacks did the farmer end up with?

Answer: Just one. The farmer had piled them all up the middle, remember? 

(Adapted from a brain teaser by Jan Weaver.)

8. THE THREE ALIENS RIDDLE

In this video riddle, you have crashed landed on a planet with three alien overlords named Tee, Eff, and Arr. There are also three artifacts on the planet, each matching a single alien. To appease the aliens, you need to match up the artifacts with the aliens—but you don't know which alien is which.

You are allowed to ask three yes-or-no questions, each addressed to any one alien. You can choose to ask the same alien multiple questions, but you don't have to.

It gets more complex, though, and this wickedly tricky riddle is best explained (both its problem and its solution) by watching the video above.

9. THE FARMER'S WILL

One day, a farmer decided to do some estate planning. He sought to apportion his farmland among his three daughters. He had twin daughters, as well as a younger daughter. His land formed a 9-acre square. He wanted the eldest daughters to get equally sized pieces of land, and the younger daughter to get a smaller piece. How can he divide up the land to accomplish this goal?

Three square illustrations.
Three possible solutions.
Chris Higgins

Answer: Shown above are three possible solutions. In each, the box marked 1 is a perfect square for one twin, and the two sections marked 2 combine to make a square of the same size for the second twin. The area marked 3 is a small perfect square for the youngest child.

(Adapted from a brain teaser by Jan Weaver.)

10. COINS

In my hand I have two American coins that are currently minted. Together, they total 55 cents. One isn't a nickel. What are the coins?

Answer: A nickel and a 50-cent piece. (Lately the U.S. 50-cent piece features John F. Kennedy.)

(Adapted from a brain teaser by Jan Weaver.)

11. THE BRIDGE RIDDLE

A student, a lab assistant, a janitor, and an old man need to cross a bridge to avoid being eaten by zombies, as shown in the video below. The student can cross the bridge in one minute, the lab assistant takes two minutes, the janitor takes five minutes, and the professor takes 10 minutes. The group only has one lantern, which needs to be carried on any trip across. The zombies arrive in 17 minutes, and the bridge can only hold two people at a time. How can you get across in the time allotted, so you can cut the rope bridge and prevent the zombies from stepping on the bridge and/or eating your brains? (See the video for more details!)

Answer: The student and lab assistant go together first, and the student returns, putting three minutes total on the clock. Then, the professor and the janitor take the lantern and cross together, taking 10 minutes, putting the total clock at 13 minutes. The lab assistant grabs the lantern, crosses in two minutes, then the student and lab assistant cross together just in the nick of time—a total of 17 minutes.

12. LITTLE NANCY ETTICOAT

Here's a nursery rhyme riddle:

Little Nancy Etticoat
In her white petticoat
With a red nose—
The longer she stands
The shorter she grows

Given this rhyme, what is "she?"

Answer: A candle.

(Adapted from a brain teaser by J. Michael Shannon.)

13. THE GREEN-EYED LOGIC PUZZLE

In the green-eyed logic puzzle, there is an island of 100 perfectly logical prisoners who have green eyes—but they don't know that. They have been trapped on the island since birth, have never seen a mirror, and have never discussed their eye color.

On the island, green-eyed people are allowed to leave, but only if they go alone, at night, to a guard booth, where the guard will examine eye color and either let the person go (green eyes) or throw them in the volcano (non-green eyes). The people don't know their own eye color; they can never discuss or learn their own eye color; they can only leave at night; and they are given only a single hint when someone from the outside visits the island. That's a tough life!

One day, a visitor comes to the island. The visitor tells the prisoners: "At least one of you has green eyes." On the 100th morning after, all the prisoners are gone, all having asked to leave on the night before. How did they figure it out?

Watch the video for a visual explanation of the puzzle and its solution.

Answer: Each person can't be sure whether they have green eyes. They can only deduce this fact by observing the behavior of the other members of the group. If each person looks at the group and sees 99 others with green eyes, then logically speaking, they must wait 100 nights to give the others opportunities to stay or leave (and for each to make that calculation independently). By the 100th night, using inductive reasoning, the entire group has offered every person in the group an opportunity to leave, and can figure that it's safe to go.

14. THE NUMBER ROW

The numbers one through 10, below, are listed in an order. What is the rule that causes them to be in this order?

8 5 4 9 1 7 6 10 3 2

Answer: The numbers are ordered alphabetically, based on their English spelling: eight, five, four, nine, one, seven, six, ten, three, two.

(Adapted from a brain teaser by Carl Proujan.)

15. THE COUNTERFEIT COIN PUZZLE

In the video below, you must find a single counterfeit coin among a dozen candidates. You're allowed the use of a marker (to make notes on the coins, which doesn't change their weight), and just three uses of a balance scale. How can you find the one counterfeit—which is slightly lighter or heavier than the legitimate coins—among the set?

Answer: First, divide the coins into three equal piles of four. Put one pile on each side of the balance scale. If the sides balance (let's call this Case 1), all eight of those coins are real and the fake must be in the other pile of four. Mark the legitimate coins with a zero (circle) using your marker, take three of them, and weigh against three of the remaining unmarked coins. If they balance, the remaining unmarked coin is counterfeit. If they don't, make a different mark (the video above suggests a plus sign for heavier, minus for lighter) on the three new coins on the scale. Test two of these coins on the scale (one on each side)—if they have plus marks, the heavier of those tested will be the fake. If they have minus marks, the lighter is the fake. (If they balance, the coin not tested is the fake.) For Case 2, check out the video.

16. THE ESCALATOR RUNNER

Each step of an escalator is 8 inches taller than the previous step. The total vertical height of the escalator is 20 feet. The escalator moves upward one half step per second. If I step on the lowest step at the moment it is level with the lower floor, and run up at a rate of one step per second, how many steps do I take to reach the upper floor? (Note: Do not include the steps taken to step on and off the escalator.)

Answer: 20 steps. To understand the math, take a period of two seconds. Within that two seconds, I run up two steps on my own power, and the escalator lifts me the height of an extra step, for a total of three steps—this could also be expressed as 3 times 8 inches, or two feet. Therefore, over 20 seconds I reach the upper floor having taken 20 steps.

(Adapted from a brain teaser by Carl Proujan.)

17. A RIVER CROSSING PUZZLE

In the video riddle below, three lions and three wildebeest are stranded on the east bank of a river and need to reach the west. A raft is available, which can carry a maximum of two animals at a time and needs at least one animal onboard to row it across. If the lions ever outnumber the wildebeest on either side of the river (including the animals in the boat if it's on that side), the lions will eat the wildebeest.

Given these rules, how can all the animals make the crossing and survive?

Answer: There are two optimal solutions. Let's take one solution first. In the first crossing, one of each animal goes from east to west. In the second crossing, one wildebeest returns from west to east. Then on the third crossing, two lions cross from east to west. One lion returns (west to east). On crossing five, two wildebeest cross from east to west. On crossing six, one lion and one wildebeest return from west to east. On crossing seven, two wildebeest go from east to west. Now all three wildebeest are on the west bank, and the sole lion on the west bank rafts back to the east. From there (crossings eight through eleven), lions simply ferry back and forth, until all the animals make it.

For the other solution, consult the video.

18. THE THREE WATCHES

I am marooned on an island with three watches, all of which were set to the correct time before I got stuck here. One watch is broken and doesn't run at all. One runs slow, losing one minute every day. The final watch runs fast, gaining one minute every day.

After being marooned for a moment, I begin to worry about timekeeping. Which watch is most likely to show the correct time if I glance at the watches at any particular moment? Which would be least likely to show the correct time?

Answer: We know that the stopped watch must tell the correct time twice a day—every 12 hours. The watch that loses one minute per day will not show the correct time until 720 days into its cycle of time loss (60 minutes in an hour times 12 hours), when it will momentarily be exactly 12 hours behind schedule. Similarly, the watch that gains one minute a day is also wrong until 720 days after its journey into incorrectness, when it will be 12 hours ahead of schedule. Because of this, the watch that doesn't run at all is most likely to show the correct time. The other two are equally likely to be incorrect.

(Adapted from a brain teaser by Carl Proujan.)

19. EINSTEIN'S RIDDLE

In this riddle, erroneously attributed to Albert Einstein, you're presented with a series of facts and must deduce one fact that's not presented. In the case of the video below, a fish has been kidnapped. There are five identical-looking houses in a row (numbered one through five), and one of them contains the fish.

Watch the video for the various bits of information about the occupants of each house, the rules for deducing new information, and figure out where that fish is hiding! (Note: You really need to watch the video to understand this one, and the list of clues is helpful too.)

Answer: The fish is in House 4, where the German lives.

20. MONKEY MATH

Three castaways and a monkey are marooned together on a tropical island. They spend a day collecting a large pile of bananas, numbering between 50 and 100. The castaways agree that the next morning the three of them will divide up the bananas equally among them.

During the night, one of the castaways wakes up. He fears that the others might cheat him, so he takes his one-third share and hides it. Since there is one banana more than a quantity which could be divided equally into thirds, he gives the extra banana to the monkey and goes back to sleep.

Later in the night, a second castaway awakes and repeats the same behavior, plagued by the same fear. Again, he takes one-third of the bananas in the pile and again the quantity is one greater than would allow an even split into thirds, so he hands the extra banana to the monkey and hides his share.

Still later, the final castaway gets up and repeats the exact same procedure, unaware that the other two have already done it. Yet again, he takes a third of the bananas and ends up with one extra, which he gives to the monkey. The monkey is most pleased.

When the castaways meet in the morning to divide the banana loot, they all see that the pile has shrunk considerably, but say nothing—they're each afraid of admitting their nighttime banana thievery. They divide the remaining bananas three ways, and end up with one extra for the monkey.

Given all this, how many bananas were there in the original pile? (Note: There are no fractional bananas in this problem. We are always dealing with whole bananas.)

Answer: 79. Note that if the pile were bigger, the next possible number that would meet the criteria above would be 160—but that's outside the scope listed in the second sentence ("between 50 and 100") of the puzzle.

(Adapted from a brain teaser by Carl Proujan.)

21. THE VIRUS RIDDLE

In the video below, a virus has gotten loose in a lab. The lab is a single story building, built as a 4x4 grid of rooms, for a total of 16 rooms—15 of which are contaminated. (The entrance room is still safe.) There's an entrance at the northwest corner and an exit at the southeast corner. Only the entrance and exit rooms are connected to the outside. Each room is connected to its adjacent rooms by airlocks. Once you enter a contaminated room, you must pull a self-destruct switch, which destroys the room and the virus within it—as soon as you leave for the next room. You cannot re-enter a room after its switch has been activated.

If you enter via the entrance room and exit via the exit room, how can you be sure to decontaminate the entire lab? What route can you take? See the video for a great visual explanation of the problem and the solution.

Answer: The key lies in the entrance room, which is not contaminated and which you may therefore re-enter after exiting it. If you enter that room, move one room to the east (or the south) and decontaminate it, then re-enter the entrance room and destroy it on your way to the next room. From there, your path becomes clear—you actually have four options to complete the path, which are shown in the video above. (Sketching this one on paper is an easy way to see the routes.)

22. THE IN-LAW CONUNDRUM

According to puzzle book author Carl Proujan, this one was a favorite of author Lewis Carroll.

The prime minister is planning a dinner party, but he wants it to be small. He doesn't like crowds. He plans to invite his father's brother-in-law, his brother's father-in-law, his father-in-law's brother, and his brother-in-law's father.

If the relationships in the prime minister's family happened to be arranged in the most optimal manner, what would be the minimum possible number of guests be at the party? Note that we should assume that cousin marriages are permitted.

Answer: One. It is possible, through some complex paths in the prime minister's family, to get the guest list down to one person. Here's what must be true: The PM's mother has two brothers. Let's call them brother 1 and brother 2. The PM also has a brother who married the daughter of brother 1, a cousin. The PM also has a sister who married the son of brother 1. The host himself is married to the daughter of brother 2. Because of all this, brother 1 is the PM's father's brother-in-law, the PM's brother's father-in-law, the PM's father-in-law's brother, and the PM's brother-in-law's father. Brother 1 is the sole guest at the party.

(Adapted from a brain teaser by Carl Proujan.)

23. THE PRISONER BOXES RIDDLE

In the video, ten band members have had their musical instruments randomly placed in boxes marked with pictures of musical instruments. Those pictures may or may not match up with the contents.

Each member gets five shots at opening boxes, trying to find their own instrument. Then, they must close the boxes. They're not allowed to communicate about what they find. If the entire band fails to find their instruments, they'll all be fired. The odds of them randomly guessing their way through this is one in 1024. But the drummer has an idea that will radically increase their odds of success, to more than 35 percent. What's his idea?

Answer: The drummer told everyone to first open the box with the picture of their instrument. If their instrument is inside, they're done. If not, the band member observes what instrument is found, then opens the box with that instrument's picture on it—and so forth. Watch the video for more on why this works mathematically.

24. S-N-O-W-I-N-G

One snowy morning, Jane awoke to find that her bedroom window was misty with condensation. She drew the word "SNOWING" on it with her finger. Then she crossed out the letter N, turning it into another English word: "SOWING." She continued this way, removing one letter at a time, until there was just one letter remaining, which is itself a word. What words did Jane make, and in what order?

Answer: Snowing, sowing, owing, wing, win, in, I.

(Adapted from a brain teaser by Martin Gardner.)

25. THE MYSTERY STAMPS

While on vacation on the island of Bima, I visited the post office to send some packages home. The currency on Bima is called the pim, and the postmaster told me that he only had stamps of five different values, though these values are not printed on the stamps. Instead, the stamps have colors.

The stamps were black, red, green, violet, and yellow, in descending order of value. (Thus the black stamps had the highest denomination and yellow the lowest.)

One package required 100 pims worth of stamps, and the postmaster handed me nine stamps: five black stamps, one green stamp, and three violet stamps.

The other two packages required 50 pims worth each; for those, the postmaster handed me two different sets of nine stamps. One set comprised one black stamp and two each of the other colors. The other set was five green stamps, and one each of the other colors.

What would be the smallest number of stamps needed to mail a 50-pim package, and what colors would they be?

Answer: Two black stamps, one red stamp, one green stamp, and one yellow stamp. (It may help to write out the stamp formulas given above using the various b, r, g, v, and y. Because we know that b > r > g > v > y, and we have three described cases, we can do some algebra to arrive at values for each stamp. Black stamps are worth 18 pim, red are worth 9, green are worth 4, violet are worth 2, and yellow are worth 1.)

(Adapted from a brain teaser by Victor Bryant and Ronald Postill.)

Sources: Brain Teasers by Jan Weaver; Brain Teasers & Mind Benders by Charles Booth-Jones; Riddles and More Riddles by J. Michael Shannon; Brain Teasers Galore: Puzzles, Quizzes, and Crosswords from Science World Magazine, edited by Carl Proujan; The Arrow Book of Brain Teasers by Martin Gardner; The Sunday Times Book of Brain Teasers, edited by Victor Bryant and Ronald Postill.

25 Species That Have Made Amazing Comebacks

iStock.com/guenterguni
iStock.com/guenterguni

Conservationists can't afford to become complacent. When it comes to rescuing endangered species, progress is an ongoing effort. Still, we can take comfort in the knowledge that many organisms once on the brink of extinction or endangerment have made tremendous comebacks with our help. Just look at what happened to these 25 plants and animals.

1. THE BALD EAGLE

close-up of a bald eagle
Sherrodphoto/iStock via Getty Images

For much of the 20th century, this American icon was in jeopardy. Habitat loss, hunting, and the widespread use of DDT—an insecticide that weakens avian eggshells—once took a major toll on bald eagles. By 1963, the species population in the lower 48 states had fallen from an estimated 100,000 individuals to just 417 wild pairs. To turn things around, the U.S. government passed a series of laws, including a 1973 ban on DDT that was implemented by the Environmental Protection Agency (EPA). These efforts paid off; today, approximately 10,000 wild breeding pairs are soaring around in the lower 48.

2. THE ARABIAN ORYX

an arabian oryx in the desert
Clendenen/iStock via Getty Images

The Arabian oryx is a desert antelope indigenous to the Middle East. Reckless hunting devastated the species, which became essentially extinct in the wild during the early 1970s. However, a few were still alive and well in captivity. So, in the 1980s, American zoos joined forces with conservationists in Jordan to launch a massive breeding program. Thanks to their efforts, the oryx was successfully reintroduced to the Arabian Peninsula, where over 1000 wild specimens now roam (with a captive population of about 7000).

3. THE GRAY WOLF

Gray wolf stalking prey in the snow
hkuchera/iStock via Getty Images

Even well-known conservationists like Theodore Roosevelt used to vilify America’s wolves. Decades of bounty programs intended to cut their numbers down to size worked all too well; by 1965, only 300 gray wolves remained in the lower 48 states, and those survivors were all confined to remote portions of Michigan and Minnesota. Later, the Endangered Species Act enabled the canids to bounce back in a big way. Now, 5000 of them roam the contiguous states.

4. THE BROWN PELICAN

Brown pelican
CarolinaBirdman/iStock via Getty Images

Louisiana’s state bird, the brown pelican, is another avian species that was brought down by DDT. In 1938, a census reported that there were 500 pairs living in Louisiana. But after farmers embraced DDT in the 1950s and 1960s, these once-common birds grew scarce. Things got so bad that, when a 1963 census was conducted, not a single brown pelican had been sighted anywhere in Louisiana. Fortunately, now that the era of DDT is over, the pelican is back with a vengeance on the Gulf Coast and no longer considered endangered.

5. ROBBINS’ CINQUEFOIL

Robbins' Cinquefoil
U.S.D.A. Forest Service, Wikimedia Commons // Public Domain

Noted for its yellow flowers, Robbins’s cinquefoil (Potentilla robbinsiana) is an attractive, perennial plant that’s only found in New Hampshire’s White Mountains and Franconia Ridge. Collectors once harvested the cinquefoil in excessive numbers and careless backpackers trampled many more to death. In response, the U.S. Fish and Wildlife Service re-routed hiking trails away from the flower’s wild habitats. This, along with a breeding program, rescued the Robbins' cinquefoil from the brink of extinction.

6. THE AMERICAN ALLIGATOR

American alligator on a log
Joe Pearl Photography/iStock via Getty Images

With its population sitting at an all-time low, the American alligator was recognized as an endangered species in 1967. Working together, the Fish and -Wildlife Service and governments of the southern states took a hard line against gator hunting while also keeping tabs on free-ranging alligator populations. In 1987, it was announced that the species had made a full recovery [PDF].

7. THE NORTHERN ELEPHANT SEAL

Elephant seal winking
franksvalli/iStock via Getty Images

Due to its oil-rich blubber, the northern elephant seal became a prime target for commercial hunters. By 1892, some people were beginning to assume that it had gone extinct. However, in 1910, it was discovered that a small group—consisting of fewer than 100 seals—remained on Guadalupe Island. In 1922, Mexico turned the landmass into a government-protected biological preserve. From a place of security, that handful of pinnipeds bred like mad. Today, every single one of the 160,000 living northern elephant seals on planet Earth are that once-small group’s descendants.

8. THE HUMPBACK WHALE

humpback whale
miblue5/iStock via Getty Images

Did you know that the world’s humpback whale population is divided into 14 geographically-defined segments? Well, it is—and in 2016, the National Ocean and Atmospheric Administration (NOAA) informed the press that nine of those clusters are doing so well that they no longer require protection under the U.S. Endangered Species Act. The cetaceans’ comeback is a huge win for the International Whaling Commission, which responded to dwindling humpback numbers by putting a ban on the hunting of this species in 1982. (That measure remains in effect.)

9. The Fin Whale

Fin whale near Greenland
Aqqa Rosing-Asvid—Visit Greenland, Wikimedia Commons // CC BY 2.0

Commercial whaling decimated global populations of fin whales, the second-largest species of baleen whale on Earth. In the 1970s, international coalitions banned fin whale hunting in the Southern Hemisphere and the North Pacific, and legal catches were reduced in the North Atlantic in the 1990. Though three countries—Norway, Iceland, and Japan—continue to hunt whales for oil and meat, the IUCN reported in 2018 that the fin whale population has doubled since the 1970s.

10. THE WHITE RHINO

White rhino adult and calf
Marcello Calandrini/iStock via Getty Images

Make no mistake: The long-term survival of Earth’s largest living rhino is still very uncertain because poachers continue to slaughter them en masse. Nevertheless, there is some good news. Like black-footed ferrets and northern elephant seals, white rhinos were once presumed to be extinct. But in 1895, just under 100 of them were unexpectedly found in South Africa. Thanks to environmental regulations and breeding efforts, more than 20,000 are now at large.

11. THE WILD TURKEY

two male wild turkeys
Lois_McCleary/iStock via Getty Images

It’s hard to imagine that these birds were ever in any real trouble, and yet they looked destined for extinction in the early 20th century. With no hunting regulations to protect them, and frontiersmen decimating their natural habitat, wild turkeys disappeared from several states. By the 1930s, there were reportedly fewer than 30,000 left in the American wilderness. Now, over 6 million are strutting around. So what changed? A combination of bag limits set by various agencies and an increase in available shrublands.

12. THE BLACK-FOOTED FERRET

black-footed ferret
USFWS Mountain-Prairie, Flickr // CC BY 2.0

North America’s only indigenous ferret is a prairie dog-eater that was written off as “extinct” in 1979. But the story of this animal took a surprising twist two years later, when a Wyoming dog gave a freshly dead one to its owner. Amazed by the canine’s find, naturalists soon located a wild colony. Some of these ferrets were then inducted into a breeding program, which helped bring the species’ total population up to over 1000.

13. THE CALIFORNIA CONDOR

portrait of a California condor
SumikoPhoto/iStock via Getty Images

Since 1987, the total number of California condors has gone up from 27 birds to about 450, with roughly 270 of those being wild animals (according to a 2016 count by the FWS). With its 10-foot wingspan, this is the largest flying land bird in North America.

14. THE GOLDEN LION TAMARIN

two tamarins
Enjoylife2/iStock via Getty Images

A flashy orange primate from Brazil’s Atlantic Forest, the golden lion tamarin has been struggling to cope with habitat destruction. The species hit rock-bottom in the early 1970s, when fewer than 200 remained in the wild. A helping hand came from the combined efforts of Brazil’s government, the World Wildlife Federation, public charities, and 150 zoos around the world. There’s now a healthy population of captive tamarins tended to by zookeepers all over the globe. Meanwhile, breeding, relocation, and reintroduction campaigns have increased the number of wild specimens to around 1700—although urban sprawl could threaten the species with another setback. But at least the animal doesn’t have a PR problem: Golden lion tamarins are so well-liked that the image of one appears on a Brazilian banknote.

15. THE ISLAND NIGHT LIZARD

island night lizard
Ryan P. O'Donnell, Wikimedia Commons // CC BY-SA 3.0

Native to three of California’s Channel Islands, this omnivorous, 4-inch reptile was granted federal protection under the Endangered Species Act in 1977. The designation couldn’t have come at a better time, as introduced goats and pigs were decimating the night lizard’s wild habitat in those days. But now that wild plants have been reestablished under FWS guidance, more than 21 million of the reptiles are believed to be living on the islands.

16. THE OKARITO KIWI

Small, flightless, island birds usually don’t fare well when invasive predators arrive from overseas. (Just ask the dodo.) New Zealanders take great pride in the five kiwi species found exclusively in their country, including the Okarito kiwi, which is also known as the Okarito brown or rowi kiwi. These animals have historically suffered at the hands of introduced dogs and stoats. But recently, there’s been some cause for celebration. Although there were only about 150 Okarito kiwis left in the mid-1990s, conservation initiatives have triggered a minor population boom, with about 400 to 500 adult birds now wandering about. Taking note of this trend, the International Union for Conservation of Nature (IUCN) has declared that the Okarito kiwi is no longer endangered.

17. THE BROWN BEAR

brown bear with three cubs
LuCaAr/iStock via Getty Images

Let’s clear something up: The famous grizzly bear technically isn’t its own species. Instead, it is a North American subspecies of the brown bear (Ursus arctos), which also lives in Eurasia. Still, grizzlies are worth mentioning here because of just how far they’ve come within the confines of Yellowstone National Park. In 1975, there were only 136 of them living inside the park. Today, approximately 700 of them call the place home. In 2018, the FWS delisted the Greater Yellowstone population grizzlies from Endangered Species Act protection, but reinstated them in July 2019 as "threatened" to comply with a Montana court ruling.

18. THE THERMAL WATER LILY

thermal water lily

With pads that can be as tiny as one centimeter across, the thermal water lily is the world’s smallest water lily. Discovered in 1985, it was only known to grow in Mashyuza, Rwanda, where it grew in the damp mud surrounding the area’s hot spring. Or at least it did. The thermal water lily seems to have disappeared from its native range. Fortunately, before the species went extinct in the wild, some seeds and seedlings were sent to London’s Royal Botanic Gardens at Kew. There, horticulturalists figured out a way to make the lilies flower in captivity, and managed to saved the species.

19. THE PEREGRINE FALCON

Peregrine falcon
ca2hill/iStock via Getty Images

When a peregrine falcon dives toward its airborne prey, the bird-eating raptor has been known to hit speeds of up to 242 miles per hour. The species endured a plummet of a different sort when DDT dropped its population. In the first few decades of the 20th century, there were around 3900 breeding pairs in the United States. By 1975, the number of known pairs had been whittled down to 324. Things got better after the insecticide was banned, and according to the FWS, somewhere between 2000 and 3000 peregrine falcon pairs currently patrol the skies in the United States, Canada, and Mexico.

20. PRZEWALSKI'S HORSE

Przewalski's horse in autumn field
Nemyrivskyi Viacheslav/iStock via Getty Images

There are a few different subspecies of wild horse, all of which are endangered. One variant is the Przewalski's horse (Equus ferus perzewalskii) from Mongolia. It completely vanished from that nation during the 1950s, but by then assorted zoos around the world had started breeding them. From 1992 to 2004, some 90 captive-born horses were released into Mongolia. They thrived and around 300 are living in their native habitat today, while other populations have been successfully introduced in Hungary and Russia (including in the Chernobyl exclusion zone).

21. THE NORTH AMERICAN BEAVER

North American beaver
webmink/iStock via Getty Images

No one knows how many hundreds of millions [PDF] of these buck-toothed rodents were living on the continent before European fur traders showed up. But after two centuries of over-trapping, spurred by the lucrative pelt trade, the number of North American beavers had shrunk to an abysmal 100,000 in 1900. Their fortunes reversed when restocking programs were implemented in the U.S. and Canada. Nowadays, somewhere between 10 and 15 million beavers live in those countries. Thanks to beaver's amazing landscaping talents, many property owners have come to see them (unfairly) as pests.

22. THE CAFÉ MARRON

Cafe Marron tree
Abu Shawka, Wikimedia Commons // CC0 1.0

Rodrigues Island in the Indian Ocean once gave biologists a chance to raise the (near) dead. This landmass is the home of a small tree with star-shaped flowers called the café marron. It was thought that the plant had long since died out when a single specimen was found by a schoolboy named Hedley Manan in 1980. As the only surviving member of its species known to humankind, that lone plant assumed paramount importance. Cuttings from the isolated café marron were used to grow new trees at England’s Royal Botanical Gardens at Kew. Right now, there are more than 50 of these plants—and all of them can have their ancestry traced straight back to that one holdout tree.

23. THE WEST INDIAN MANATEE

Manatee with fish
U.S. Fish and Wildlife Service, Wikimedia Commons // Public Domain

A docile, slow-moving marine mammal with a taste for sea grasses, the Floridian subspecies of the West Indian manatee is a creature that does not react well to razor-sharp propellers. Collisions with boats are a significant threat, and the danger won’t go away altogether. Still, the passage of tighter boating regulations has helped the Sunshine State rejuvenate its manatee population, which has more than tripled since 1991.

24. THE BURMESE STAR TORTOISE

Burmese star tortoise
LagunaticPhoto/iStock via Getty Images

The pet trade did a number on these guys. Beginning in the 1990s, wildlife traffickers harvested Burmese star tortoises until they effectively became “ecologically extinct” in their native Myanmar. Luckily, conservationists had the foresight to set up breeding colonies with specimens who’d been confiscated from smugglers. The program started out with fewer than 200 tortoises in 2004; today, it has more than 14,000 of them. “Our ultimate objective is to have about 100,000 star tortoises in the wild,” Steve Platt, a herpetologist who’s been taking part in the initiative, said in a Wildlife Conservation Society video.

25. THE GIANT PANDA

panda in tree
DennisvandenElzen/iStock via Getty Images

Here we have it: the poster child for endangered animals everywhere … except that the giant panda is no longer endangered. In 2016, the IUCN changed its status from “endangered” to “vulnerable.” There’s still a chance that we could lose the majestic bamboo-eater once and for all someday, but the last few years have offered a bit of hope. Between 2004 and 2014, the number of wild pandas increased 17 percent. The welcome development was made possible by enacting a poaching ban and establishing new panda reserves. It’s nice to know that, with the right environmental policies, we can make the future brighter for some of our fellow creatures.

This story first ran in 2017.

10 Frank Facts About the Wienermobile

Business Wire
Business Wire

This year marks the 83rd anniversary of the Oscar Mayer Wienermobile, that effortlessly charming, street-legal marketing tool on wheels. The next time you’re in the vicinity of one—a fleet of six makes up to 1400 stops annually—take the time to reflect on the past, present, and future of history’s most famous locomoting hot dog.

1. The Wienermobile started as a kind of land sub. 


Oscar Mayer

In 1936, Carl Mayer, nephew of hot dog scion Oscar Mayer, suggested a marketing idea to his uncle: build a 13-foot-long mobile hot dog and cruise around the Chicago area handing out his “German wieners” to stunned pedestrians. Crafted from a metal chassis, the vehicle was operated by Carl, who could usually be seen with his torso sticking out from the cockpit.

2. The Wienermobile was once driven by "Little Oscar."

Throughout the 1930s, ‘40s, and ‘50s, Oscar Mayer enlisted various little people to portray “Little Oscar,” a company mascot sporting a chef’s hat. Little Oscar soon assumed piloting duties for the Wienermobile, waving to crowds and dispensing wiener whistles that kids could use to alert other children to the presence of the car in their neighborhood. Performer George Malchan portrayed the character from 1951 to 1987.

3. The Wienermobile disappeared for decades.

While novelty automobiles were all the rage circa World War II, Oscar Mayer saw interest wane in the 1960s and 1970s, as kitsch gave way to more contemporary advertising campaigns. But when the company put a Wiener back on the road for its 50th anniversary in 1986, they discovered a whole generation of consumers who were nostalgic for the car. The company ordered six new models in 1988.

4. Wienermobile drivers train at Hot Dog High.

Since resurrecting the marketing campaign, Oscar Mayer has trained aspiring Wienermobile drivers at Hot Dog High in Madison, Wisconsin. The company receives 1000 to 1500 applications for the 12 available positions annually, typically from college graduates looking for a road trip experience. Those selected for duty are given 40 hours of instruction and assigned a different region of the country. The company tracks their routes with a GPS.

5. Wienermobile passengers ride "shotbun."

Oscar Mayer Wienermobile
Tim Boyle/Getty Images

Wienermobile motorists—a.k.a. Hotdoggers—typically ride in pairs, with the driver keeping an eye on the road and the passenger acknowledging and waving to passersby who want to interact with the vehicle. This is known as riding “shotbun,” and the greetings are mandatory. Some occupants have reported that even after going off-duty, they’ll keep waving to other drivers out of habit.

6. The Wienermobile interior is just as delicious.

Wienermobile fans who are invited to board—and promise to fasten their “meat belts” before rolling—are treated to a rare peek inside the vehicle’s interior. Ketchup- and mustard-colored upholstery surround the six seats, with condiment "stains" dotting the floor; for parades, occupants can wave from the “bunroof.” Two accent hot dogs are parked on the dashboard.

7. The Wienermobile once crashed into a house.

Though it can be challenging to pilot an enormous hot dog, most Wienermobiles log mileage without incident. A rare exception: a 2009 accident near Milwaukee, Wisconsin, when a driver attempted to back the vehicle out of a residential driveway, thought she was in reverse, but shot forward and bored into an unoccupied home.

8. Al Unser Jr. drove the Wienermobile for laps at the Indy 500.

While one might expect the Wienermobile to have the handling of a tube-shaped camper, some models were surprisingly nimble. Race car driver Al Unser Jr. took to the Indianapolis Motor Speedway in 1988 and drove it for laps. The dog reached an impressive 110 miles per hour.

9. There's a version of the Wienermobile called a "Wienie-Bago."

Oscar Mayer Wienermobile WIENIE-BAGO
Oscar Mayer

Super Bowl attendees who couldn’t snag a hotel room in San Francisco for the 2016 showdown between the Carolina Panthers and Denver Broncos had a pork-based solution: Oscar Mayer auctioned off two nights in their Wienie-Bago, an RV that sleeps four. Missed it? If you're in Chicago, you can rent a Wienermobile that sleeps two for $136 a night. A bed, outdoor dining area, and a fridge stocked with hot dogs are all included.

10. You can buy a miniature Wienermobile.

For the 2015 gift-giving season, Oscar Mayer issued a limited-edition, remote-controlled version of the Wienermobile. The 22.5-inch-long mini-dog sent collectors scrambling on Cyber Monday, when the company released just 20 for purchase at a time. The Rover is able to hold two hot dogs for transport across picnic tables. You can still find them on eBay.

SECTIONS

arrow
LIVE SMARTER