The unique appearance of each person on the planet is the cumulative result of generations of inherited traits, mixed with the traits of their chosen partners, to produce the next generation. But while is common knowledge things such as skin color, eye color and hair color are inherited, there are many other things that are passed through families, not always to good effect. There are many genetic diseases, for example, that we might wish were not passed on.

But genetics also has its lighter side. Some of the traits that have been passed from generation to generation without dying out appear to have little or no benefit to mankind from an evolutionary perspective.

But they do make a good talking point.

See Also: 10 Fruits, Nuts, And Vegetables You Did Not Know Were Man-Made

10 Tongue rolling

Around two thirds of people are able to roll each side of their tongue together to form a tube shape, without the least effort, whilst the rest are cursed with flat tongues. One of the more pointless genetic traits, the phenomenon was first noticed by pioneer geneticist Alfred Sturtevant in 1940. He maintained that the ability to roll tongues was a Mendelian trait, meaning that it needed only to be passed down from one of the parents rather than as a blend of both, hence its prevalence. Other Mendelian traits include eye colour and freckles.

Unlike freckles, however, tongue rolling can sometimes be managed. With a lot of practice non-rollers can learn to twist their tongue into a tube shape, though why they would want to is beyond us. A study at Delaware’s Department of Biological Sciences involving 33 non tongue-rollers showed that after a solid month of practice, 1 person managed to master the ‘skill’. Could it be that the other 32 just weren’t bothered?

It is also true that the ability to roll your tongue is not always down to genetics, as studies have shown that sometimes non-genetic causes can also affect the ability of the tongue to bend. And, it seems, there are a few unfortunate people who are neither rollers nor non-rollers, being able to curl their tongues just a little.^[10]

Weirdos.

9 Hairy knuckles

If you have hair on the upper part of your fingers, between your knuckles (on the mid-phalangeal joint), it may not be because of your latent Jekyll and Hyde tendencies, but because of your genes.

Anthropologists have studied these stray strands for nearly a hundred years. We can only surmise that it must have been a slow century. It is said to appear most often on the fourth finger, or ring finger, and never appears on thumbs. It is also said to be most common among Caucasians, though the reason for this is not clear.

Researchers believe that the cause may be related to prenatal exposure to androgens, the hormones related to the development of male characteristics. The trait is said to be dominant, meaning that it must be present in one or both of the parents, though the gene for hirsute digits has yet to be isolated.^[9]

Surely, there’s Nobel Prize right there?

8 Hand clasping

We may not always be aware of it, but every time we clasp our hands together, we are said to be following the hand-clasping traits of our ancestors. At least one of our parents is likely to fold their hands in the same way we do. Which would, perhaps, be impressive if there was a large number of options. Basically, however, you can clasp your right hand over your left, or your left hand over your right.

So, in a fifty-fifty choice it would be a fair bet that one of our parents clasped hands the same way we do, wouldn’t it? Researchers, however, have gone to great lengths to study this ‘phenomena’, and studies have shown that around 55% of people are left-hand-claspers, 44% are right-hand-claspers, while 1% refuse to be put in a box, and report having no preference.

Not satisfied with these results, researchers went further and researched the family genetics of their subjects, and discovered that the preference follows the same model of genetic inheritance that governs left or right handedness, but that their preference for hand clasping was not related to which hand was dominant.^[8]

Spooky!

The same research also discovered the link between hand clasping preferences and arm folding preferences, and the somewhat anomalous findings that menstruating women often changed their minds about which they preferred.

We are not even going to touch that joke.

7 Free Earlobes

If you ever really look at an ear, it starts to look weird. Ears come in all shapes and sizes, and one might think that the ears you get are just down to dumbo luck. But while the shape, size and sticky-outness may be down to chance, your earlobes, it seems, are the result of genetics.

Ears are unique. It is believed that no 2 ears are exactly alike (except, possibly, the one on the other side of your head). The shape of the earlobe, however, is determined by an allele gene, of which, as with all genes, we will receive 2 copies, one from each parent.

Earlobes may seem to have no real purpose, except, perhaps, as an appendage to hang jewelry from, but they are believed to help keep our ears warm due to their generous blood supply, and may even help us maintain balance. The lobe also contains an unusually large number of nerve endings, which is why it is often considered an erogenous zone.

There are 2 major types of earlobes, free and attached. Free earlobes are the most common, where a portion of skin hangs below the point at which it is attached to the side of the head. The free earlobe is thought to be the result of a dominant gene. Attached earlobes, however, tend to be smaller in size and do not hang freely. They are thought to be the result of a recessive gene. However, to date, no discernible benefit has been discovered in the possession of either type of lobe.^[7]

Because ears are weird.

6 Sneezing

Most sneezing, of course, is not genetic. Most often it is caused by a virus, an allergy, or environmental factors such as a dusty room. Some types of sneezes, however can have a genetic link.

Some people have an inherited sneeze reflex that is most often linked to exposure to bright light, but can be triggered by other causes too. This photic sneeze reflex, wittily dubbed ACHOO syndrome (which stands for “Autosomal dominant Compelling Helio-Ophthalmic Outburst”, because “Genetically Induced Sneezing” just wasn’t funny enough), is thought to affect between 11 and 35 percent of the population, with Caucasian females being most affected.

The sneezing is a dominant trait, meaning that if one of your parents has the syndrome, there is a 50% chance that you will also have it. However, the syndrome often goes unrecorded because, well, people sneeze a lot. The exact gene responsible for these sneeze attacks has yet to be identified. People with the condition can expect to sneeze up to 40 times each time they walk into bright light, after which their body will adjust.^[6]

There is no treatment for the condition, though it can be managed with tissues.

5 A Bent Pinkie Finger

Although not always the result of genetics, a little finger that appears to be bow outwards, can often be said to be an inherited trait. If you want to find the reason your finger is a bit crooked, it may be worth checking out your parents hands first, since if one of your parents has a crooked pinkie, there will be a 50% chance that they will be passing that on.

As with a lot of ‘conditions’ the bent finger may have other non-genetic causes, including injury or disease, and the degree of ‘bentness’ has also been a matter that has concerned researchers. What angle does a finger need to be, in order to be considered ‘bent’? Is it the angle that is inherited, or just the bentness?

Clearly, much more work needs to be done in this vital area. The good news is that corrective surgery is available should the angle of bentness become acute.^[5]

4 A Widow’s Peak

It is generally known that male baldness can be linked to genes inherited from the mother. The X chromosome of the mother can contain a genetic predisposition to baldness, although it is not the only cause. Genes passed on from the father can also be a factor, although the chances are higher that the ‘faulty gene’ was passed by the mother where baldness occurs before the age of 40. Hair loss can also be caused by environmental factors, particularly smoking and drinking.

The case for a genetic cause of hair loss in a widow’s peak, however, is much stronger. The distinctive v-shaped hair-line is a dominant trait that can be passed on from father or mother, and both men and women can have a widow’s peak, although, it is much less noticeable in women because they do not tend to lose their hair.

The ‘peak’ refers to a triangular shaped hairline, which becomes more pronounced with hair-loss. Although the peak is hereditary, it does not necessarily mean that baldness will follow as a result.^[4]

Although, it probably will.

3 A Long Second Toe

‘Morton’s toe’ is an inherited condition where the second toe is longer than the big toe, and occasionally, the third toe is also elongated. Estimates vary on the number of people who have the ‘condition’, which is named after an orthopaedic surgeon, rather than a man with unusually long foot digits, but it can affect anywhere between 3% and 20% of the population.

Morton believed that the long toe may have been a throw-back to a prehuman era when our ape-like selves used a ‘grasping toe’. This theory, however, has never been proved. Shoe-fitters are apt to call this shape the ‘Greek foot’ after the classical sculptures from Ancient Greece where the long second toe was considered the most aesthetically pleasing. The Statue of Liberty boasts a Morton’s toe.^[3]

It is not known whether she inherited it from her mother or her father.

2 A Shock of White Hair

A white patch of hair, usually at the front of the head can be the result of an inherited trait. The streak is known as poliosis, or a ‘Mallen Streak’ after a family in a TV programme who all had a distinctive white patch of hair. Poliosis can affect not just the hair, but also the eyebrows, skin and even eyelashes.

Where the condition is not genetic, the patches may a symptom of an illness. Despite popular myths, however, hair cannot turn instantly white from shock.

For those with inherited poliosis, there appears to be no associated conditions, and no downsides, except a distinctive look that is particularly favoured by devilish women with a penchant for spotty dogs.^[2]

1 Tone Deafness

Tone deafness, and its antithesis, perfect pitch, can both be inherited characteristics.

Known as Congenital Amusia, (perhaps because it makes people laugh when you try to sing), inherited tone deafness is a condition in which sufferers are unable to recognize and distinguish musical pieces. They cannot recognize a song from its tune alone, and cannot detect when a song is sung out of tune. Studies have also shown that those with the condition are not able to detect a striking ‘bum note’ in a tune, an ability which most babies are able to demonstrate.

Although it can manifest as part of a brain injury, the vast majority of those who are tone deaf have no other symptoms, and suffer no hardships except being banned from Karaoke. Which is no hardship at all.

In particular, those with congenital amusia are unable to tell that they are singing out of tune themselves. Between 70 and 80% of people who are tone deaf have the inherited condition, and around 4% of the population are thought to be affected.^[1]

Which, perhaps, explains the popularity of dubstep.

We’ve done a list on mental illness in other animals, but that’s just the tip of the iceberg. As it turns out, we’re nowhere near as unique as greedy religious nutjobs had your ancestors believe; we’re not even the only ones with religion.

10. Knowledge-sharing

Knowledge-sharing, especially from one generation to the next, put humans at the top of the food chain. It’s basically the definition of culture. It’s also found in other species. For example, baboons teach each other the best foraging routes; fledgling birds learn how to fly by watching their parents; and rats learn safe foods by smelling each other’s breath. There are countless other examples. Even fish have their “schools,” which, as it turns out, do better with experienced teachers. But it’s not just sociable species; solitary animals also show a basis for culture. Young tortoises, for instance, learn to navigate around new obstacles by watching others do it first.

Needless to say, as species go extinct, so do their cultures. The last surviving North Atlantic right whales—all but wiped out by human whalers—now lack the knowledge of their old ancestral feeding grounds, further endangering the species. That’s not to say culture is always a good thing, though. Sometimes, established ways of life fall out of kilter with the environment and a non-adaptive culture can lead a species to oblivion. Humans are finding this out the hard way.

9. Weird trends

In the age of TikTok, human trends are getting weirder all the time. But so are other animals’. White-faced capuchin monkeys in Costa Rica exhibit a number of unusual traditions, such as smelling each other’s fingers and, as a kind of game, biting off a clump of another monkey’s fur and holding it in the mouth while the other tries to get it back. Importantly, these traditions tend to be fleeting—usually lasting roughly a decade (similar to our own decade-long fads and fashions). They’re also pretty localized, so trends seen in one group may not be in the next.

Typically, these trends have no clear survival advantage. In fact, a new trend seen in one group of the Costa Rican capuchins actually posed a threat to their survival: inserting a long, dirty finger, right up to the first knuckle, into another monkey’s eye socket just above the eyeball. Those on the receiving end are clearly uncomfortable, wincing and batting their eyelids—but they don’t try to stop it. Actually, they encourage it and the behavior can last up to an hour. You might compare it to getting a tattoo or a piercing, but with nothing to show for the pain—except, perhaps, as one theorist thinks, a strengthening of social bonds.

8. Fashion

In addition to weird behavioral trends, we also find fashion in animals. Bearded vultures, whose feathers are white, apply make-up in the form of iron-rich soil. Like human fashions, this signifies status—with the older, more dominant birds wearing the most color.

There’s even evidence for fashion in fruit flies. One study found that virgin female fruit flies preferred green-dusted males after seeing other females mate with them.

Then there are the chimps who wear a single blade of grass in their ears. It started in 2010, when a chimpanzee in Zambia spontaneously stuck one in her ear and left it there. Despite it serving no obvious purpose—certainly no direct survival purpose—other chimps followed, then others, until four different groups were doing it.

7. Drug use

Drug use is everywhere in the animal kingdom. Jaguars in the Amazon independently seek out the DMT-containing yage vine used by humans to make ayahuasca; lemurs chew on narcotic millipedes; and dolphins get high on pufferfish before floating upside down in a daze staring at their own reflections.

In fact, non-human animals like drugs so much they’re willing to put up with the downsides. Bighorn sheep addicted to lichen, for instance, grind their teeth right down to the gums scraping their drug of choice from the rocks. Spider monkeys, drunk on fermented fruit, throw up and fall out of trees. And one intoxicated moose in Sweden had the opposite problem, getting stuck in a tree instead.

Animals also use drugs to cope with bad moods. In one famous study, rats kept in small cages with nothing to engage their curious minds were more likely to choose a sweetened morphine solution over water—and they drank themselves to death on the stuff. Even fruit flies turn to booze if they don’t find a mate.

6. Facial expressions

What could be more uniquely human than a smile or a frown, or any of the emotions we display? As it turns out, facial expressions are found in many other animals. Sheep, for example, not only show facial expressions, they recognize them too. Studies have shown their ability to distinguish between calm, startled, and fearful expressions in photos of other sheep. They can even tell humans apart by looking at their faces.

Domesticated dogs are also able to produce facial expressions. Wolves in the wild don’t have the same range of movement in their eyebrows, eyes, lips, and ears, which suggests an evolutionary (or selective breeding) pressure for interspecies (human-dog) communication.

5. Sense of humor

Did humans come up with laughter? It seems unlikely. According to some researchers, it evolved from the panting of play-fighting apes. The panting/laughing sound, as in humans, reassured others that the fight wasn’t serious. Tickle any great ape today and you’ll hear the same noise (assuming they’re in a good mood).

Some apes even show signs of a more complex sense of humor. The late Koko the Gorilla, who could use American Sign Language, once tied her trainer’s shoelaces together and made the sign for “chase.” Some researchers think a sense of humor is something all mammals have, while others think it’s inherent to all animals—even insects. After all, they say, we’re continually finding out they’re more intelligent than we thought and, as Darwin observed, animal intelligence varies mainly in degree, not in kind. So far most research into non-human humor has focused on the great apes, but it’ll be interesting to see where it leads.

4. Complex language

Koko the Gorilla’s humorous use of language also shows a grasp of complexity. For example, when asked to list things that are hard, she said both “rock” and “work.” In other words, she understood the word had two meanings.

Surprisingly, though, the most complex language besides our own isn’t to be found in great apes—or even the mammals of the sea—but in prairie dogs. These highly social animals have different noises, or “words,” for different predators. Their warning call for coyotes, for example, is different to their warning call for hawks, humans, and so on. But that’s not all. They also have “describing words” for a predator’s characteristics, allowing them to say how big they are and what color and so on. This means they can form sentences. And in captivity, under laboratory conditions, they can also describe things they’ve never seen before.

So far we’ve only scratched the surface of prairie dog language. It’s one thing to match the sounds and behavior with predators, but prairie dogs are continually chatting. When their behavior doesn’t change significantly (e.g. running and hiding) in response to these noises (like ours generally doesn’t when we’re talking), it’s practically impossible to know what they’re saying.

3. Storytelling

Surely storytelling sets us apart from the rest of the animal kingdom? Stories are to humans as honey is to bees, right? From history books to video games, science to religion, telling stories is our sole occupation. As it turns out, though, many other animals do the same—including bees. The bees’ famous waggle dance, in which they use physical movements to communicate the location of food, includes information about distance, direction, difficulty of route, and the value of the prize. However you look at it, they’re sharing a narrative. And if insects can do it, why not mammals? 

It has been argued that dogs are constructing a narrative when they paw at their food bowl or scratch at the door to go out. They’re referring to problems and solutions and, in the case of wanting to go for a walk, to other locations as well.

There’s no reason to think of non-human storytelling as inferior to our own. It’s doubtful the average joe could do the waggle dance, for instance. In fact, some animals may be much better at storytelling than we could ever dream of: According to some, dolphins may use their sonar capabilities to tell stories in 3D by projecting sono-pictorial holograms for each other.

2. Spirituality

According to Jane Goodall, chimps appear to feel awe. In the course of her research she saw them swaying rhythmically to a waterfall then sitting down to watch it. This of course has features of human spirituality, but it’s impossible to say it’s the same. Other chimpanzee behaviors, for example, such as throwing gathered stones to leave markings on trees almost suggest a religion… or they might just enjoy it.

What we do know, however, is that other animals ceremonialize death. Elephants perform parades when an elephant dies, with the corpse drawing not only its own herd but members of other herds too. Interestingly, they stay close to their fallen even when a corpse attracts predators. It calls to mind the kind of courage that humans often draw from their faith, or convictions.

Dolphins do it too. In the year 2000, the corpse of a female found on a seabed near Japan was accompanied at all times by two males. Her guardians surfaced only for air. And when divers tried to remove the corpse, the males fought them off on two separate days. By the third day, the corpse had disappeared. In another case, dolphins were observed guarding the corpse of an infant and chasing off seabirds even as it rotted.

Chimps show the same kind of reverence. When a baby dies, its mother will continue to care for it, carrying and grooming it for days, weeks, or even months afterward. She’ll only stop once the corpse has decayed beyond all recognition. Other apes, including gorillas, baboons, macaques, and lemurs, also have death rituals. So do birds; crows, jays, and others often gather in trees around their fallen, apparently to mourn.

1. Cooking

Fire helped humans to dominate the Earth. As well as allowing us to live in freezing environments, it opened up our food options and sped up digestion. No other animal cooks food with fire—at least as far as we know. But some are definitely capable of it. One bonobo learned how to start a fire using fuel and matches provided by humans, which it then used to cook burgers and marshmallows—before teaching this skill to his son. Admittedly, the bonobo was repeatedly shown the film Quest for Fire to put the idea in his mind, but he still picked up the skill for himself. And, in any case, many humans today can’t start a fire even in the most favorable conditions.

Of course, there’s a lot more to cooking than fire. But humans aren’t alone in food preparation—whether for taste or digestion. Some Japanese macaques wash sweet potatoes before they eat them, and prefer to use salt water for flavor. Pigs wash their food too; they’ve been seen washing dirty apple chunks in a stream. Shrikes, meanwhile, impale their prey on thorns or barbed wire and allow them to degrade before eating. Capuchin monkeys leave palm nuts in the sun to make them easier to crack. Interestingly, bigheaded ants have a more advanced form of cooking: putting food on their larvae’s bellies, for them to spit enzymes onto it and thereby make it easier to digest.