Many people are convinced that our universe is home to other intelligent life forms, and they might be correct. However, others argue that these extraterrestrial beings are already living among us. This belief is not new. Throughout history, humans have always thought that our world is shared with other mysterious entities, often possessing magical abilities. But where did these ideas originate? The reasons are both varied and fascinating.
10. Selkies and Finfolk

In Celtic and Scandinavian folklore, selkies, also known as seal maidens (and sometimes seal grooms), are creatures capable of shifting from seals to humans. They could be captured as potential spouses by taking their empty seal skins, forcing them to remain in human form. Some experts suggest that selkie legends stem from ancient memories. Early Celtic settlers in Scotland and the Shetlands may have encountered Finnish and Lapp women, possibly marrying them. These women wore sealskin garments and used kayaks, elements that might have evolved into tales of shape-shifting seal women over time.
In the Orkney Islands, tales of the finfolk, a shape-shifting group of nomadic sorcerers, were widely believed. These skilled boatmen, who were amphibious, had a notorious habit of kidnapping humans to serve as their spouses. Sightings of finfolk surged during the Little Ice Age, when sea temperatures fell by up to 5 degrees Celsius (9 °F), and Arctic ice reached as far south as Iceland. Some historians suggest these sightings might have actually been Inuit in kayaks, who traveled east and south following the ice floes.
9. Elves

We’ve previously discussed Iceland’s widespread belief in elves, which even influences road construction. Some claim this belief is relatively new. Arni Bjornsson, from the National Museum of Iceland’s ethnological department, noted that few people genuinely believed in elves in the past. The idea gained traction in the 1970s due to hippie culture and an incident in 1971 when a “clumsy but cheerful bulldozer operator” damaged rocks near Reykjavik, blaming mischievous elves. Though no one believed him, the story made headlines and sparked an elf craze.
Elf-mania expanded during the 1986 Reykjavik summit between Mikhail Gorbachev and Ronald Reagan. With limited access to the leaders, reporters sought other stories, prompting many to ask Bjornsson about Iceland’s elf beliefs. This newfound attention further entrenched the belief in elves among Icelanders, even though the idea might have seemed absurd just two decades earlier.
Interestingly, while elves appear in many European traditions, Alaric Hall from the University of Leeds suggested they held greater importance for Iceland’s early settlers. Since Iceland was uninhabited and lacked a native population to conquer, the concept of elves filled a unique cultural role:
They are essentially indigenous beings, but they resist that identity. Like other Western Europeans during the Middle Ages and early modern period, Icelanders desired to see themselves as invaders. Elves provided a symbolic earlier population, allowing them to feel like conquerors.
Over time, these stories grew more intricate as Icelanders, facing hardships, described the elves’ lavish feasts and magnificent homes. Today, the myth aligns with romantic environmentalism and a cultural pushback against modern industrialization.
8. The Minotaur

Many ancient myths stem from early human attempts to explain geological phenomena they couldn’t comprehend. For instance, Hawaii’s violent volcanic eruptions and the resulting fertile lava flows gave rise to the goddess Pele, symbolizing both destruction and creation. Similarly, Wyoming’s Devil’s Tower, formed by erosion on a laccolith rock formation, was interpreted by local tribes as claw marks from a giant bear attempting to reach people hiding atop it.
The tale of the Minotaur shares similarities with other myths. Described as having a human body and a bull’s head, the creature’s imagery aligns with the bull’s prominence in ancient Minoan culture on Crete. Early versions of the myth didn’t focus on its appearance but instead highlighted its imprisonment beneath the Earth in a vast labyrinth, with its roars causing the ground to tremble.
Crete sits on a subduction zone, where the Nubian block, linked to Africa’s continental shelf, slides under the Aegean block, resulting in an exceptionally high frequency of earthquakes. This geological activity likely inspired the Minotaur’s “fearsome roars,” as the Minoans sought to explain the sudden tectonic shifts they experienced. The Minotaur’s half-human, half-bull form may have been a later Greek addition, influenced by tales of the bull-centric Minoan culture and pottery fragments depicting men and bulls in combat.
7. Ghosts

We’ve previously examined several potential explanations for ghostly encounters, but recent studies suggest another possibility. Swiss researchers propose that ghosts might be a brain-generated illusion, occurring when illness, exhaustion, or stress disrupts our sense of bodily location. Conflicting sensory-motor signals could create the sensation of an unseen presence, even in ordinary circumstances.
In the experiment, volunteers controlled a robotic arm with their index finger, which relayed signals to another robotic arm touching their backs. When the movements were synchronized, it felt as though they were touching their own backs. However, when the actions were delayed by just 500 milliseconds, strange sensations arose. Participants reported feeling watched, touched by invisible hands, or sensing unseen figures nearby. Two individuals found the experience so unsettling that they requested the experiment to end.
Dr. Giulio Rognini explains, “Normally, the brain integrates various signals to create a unified sense of self. However, when this system fails due to illness or, in this case, robotic interference, it can generate a second representation of the body. This alternate representation is no longer perceived as ‘me’ but as another entity, a ‘presence.’” Such disruptions in self-awareness, movement, and spatial perception can arise from brain-related medical conditions or extreme emotional states like grief. These experiences may explain beliefs in ghosts, spirits, demons, and angels.
6. Changelings

The modern myth connecting the MMR vaccine to autism has historical parallels in how pre-scientific cultures interpreted the condition. Scandinavian, Celtic, and Germanic folklore tells of children taken by fairies or supernatural beings, replaced by changelings. These substitutes were said to scream incessantly, avoid speaking, make odd noises and movements, converse with invisible beings, struggle to express emotions, and resist affection, showing little bond with their mothers. Many of these traits align with autism, which involves challenges in forming social connections, impaired communication, and repetitive behaviors.
Autistic children often seem typical at birth, with symptoms emerging later. This pattern likely fueled the belief that a healthy child was abducted and replaced by an otherworldly being. In 2005, researchers published a study in the Archives of Disease in Childhood, prompted by a mother of an autistic child who said on a news program, “The girl I gave birth to has been taken away.”
In modern times, the perception of a child's sudden change from normalcy is often attributed to Big Pharma allegedly introducing harmful substances into vaccines. Centuries ago, similar changes were blamed on supernatural entities like fairies or the Devil. A troubling aspect of changeling lore is that these children were frequently subjected to abandonment or death. A Grimm fairy tale recounts a mother whipping a changeling in a field until the Devil intervenes, replacing it with her true child. Historical records show that trials for the murder and mistreatment of supposed changelings continued into the 19th century, with the belief in such phenomena enduring into contemporary times in regions like Ireland, Bavaria, and Eastern Europe.
5. Cyclops

The Greek tales of one-eyed giants might have originated from early discoveries of ancient fossils. In 2003, remains of Deinotherium giganteum, a colossal ancestor of elephants standing 5 meters (15 ft) tall with 1.4-meter (4.5 ft) tusks, were unearthed on Crete. The skulls of these creatures were enormous, with a prominent nasal cavity in the center for the trunk. While modern scientists recognize this as evidence of a trunk, ancient Greeks might have mistaken it for a single eye socket, leading to legends of a fearsome one-eyed giant race. These massive mammals roamed the forests of southern and eastern Europe during the Miocene and Pliocene epochs, making their fossils accessible to the Greeks in various locations.
While the fossil theory explains the Cyclops myth, another intriguing possibility lies in a rare genetic disorder called holoprosencephaly, which can cause infants to be born with a single eye. This condition occurs when the embryonic forebrain fails to split into two hemispheres, resulting in a single-lobed brain and severe facial and cranial deformities.
Today, it is rare for women to carry such pregnancies to full term, but a tragic incident occurred in a New York State hospital in 1960. A child born with holoprosencephaly was left to die from starvation. A physician described the infant as a “monster” and “it,” even performing a finger amputation on the child. Such cruelty in modern times makes it easier to understand how ancient societies might have viewed these children as monstrous beings.
4. Satyrs

During the Greek and Roman eras, people believed that satyrs—mythical half-human, half-goat creatures known for their lustful behavior—were real and inhabited remote areas of the Mediterranean. Showmen displayed alleged satyr mummies in cities like Rome and Antioch to astonish visitors. Greek theater often used lifelike satyr masks crafted from skin, which modern replicas reveal to be remarkably realistic. The so-called satyr corpses exhibited in antiquity were likely fabricated by combining human mummies with masks, hooves, and tails.
Workers quarrying Triassic limestone on the islands of Paros and Chios reportedly discovered fossils resembling the gods Pan and Silenus, who share satyr-like traits such as large heads with human-like features, goat ears, hooves, and horns. While the exact nature of these fossils remains unknown, it was common for ancient people to attribute mythical significance to the fossils they encountered.
A fascinating fossil theory proposed by author Adrienne Mayor suggests that a satyr corpse exhibited in Antioch, as described by Saint Jerome, might have been a miner trapped and preserved through mummification in a salt mine collapse. This idea is supported by the 2007 discovery of “salt men” dating back to 540 BC in an Iranian salt mine. Salt mummification uniquely preserves hair, skin, bones, and organs. The salt men bore a remarkable similarity to ancient satyr depictions, with matching hair, beards, snub noses, and pronounced jaws.
3. Doppelgangers

German folklore introduces the concept of the doppelganger, or “double goer,” a twin of a living person whose presence often foretells the original’s impending death. Similar doubles appear in other cultures, such as the Norse vardyger, the Finnish efirstcomeri, and the Egyptian ka, a spiritual duplicate sharing the same thoughts and emotions as its human counterpart.
In neuroscience, encountering one’s double is known as heautoscopy, or “seeing of one’s self,” distinct from autoscopy, which relates to out-of-body experiences. Heautoscopy involves perceiving an illusory body, with the center of awareness shifting between the physical and the phantom form. These hallucinations often include intense emotions, shared physical sensations, empathy for the illusory body, and a sense of detachment from one’s actual self.
Brain imaging of individuals experiencing heautoscopic hallucinations often reveals damage to the left posterior insula and nearby cortical regions. The insular cortex integrates visual, auditory, sensory, motor, proprioceptive, and vestibular inputs with internal bodily signals, forming self-awareness and the sense of bodily identity. Given the critical role of self-perception in human existence, it’s understandable why the doppelganger phenomenon is so strongly linked to the threat of impending death.
Heautoscopic episodes may also involve sensations of weightlessness, flying, spinning, or dizziness. This could explain why, in certain folklore, doppelgangers manifest as ghostly figures and are believed to appear to the dying, reenacting malevolent deeds from their lives.
2. Incubi And Succubi

Medieval beliefs claimed that demons could assume male or female forms to sexually assault sleeping Christians, either to torment them or to impregnate women with a “demon seed.” Similar ideas were prevalent in Jewish mysticism, often associated with Lilith. In Muslim traditions, such occurrences were attributed to lustful jinn. In China, the phenomenon is called ghost oppression, while the Japanese refer to it as kanashibari, attributing it to spirits, sorcerers, or ghosts.
The most widely accepted explanation for this phenomenon is that it occurs when certain mental functions awaken while the brain remains in REM sleep. REM sleep often triggers erections in men and lubrication in women. Combined with the sensation of being awake but paralyzed, along with dreamlike thoughts, hallucinations, and heightened sensory awareness, this can evoke feelings of fear and eroticism. These sensations can easily be interpreted as encounters with malevolent supernatural entities.
Another theory suggests that the phenomenon arises from a temporary disruption in breathing and heart rate during non-REM sleep. The slowed breathing and heart rate trigger a survival response in the brain, as if the sleeper is nearing death. This panic response accelerates heart rate and breathing, and if the sleeper transitions into REM sleep, they may experience vivid imagery of incubi or succubi. This phenomenon has been connected to crib death in infants and may be associated with the activation of the diving reflex, a crucial survival mechanism for aquatic animals like seals and water birds.
1. Menehune

Hawaiian folklore tells of a secretive group of small beings dwelling in hidden valleys or forests, renowned for their exceptional craftsmanship and engineering skills. These beings, ranging from a few inches to 0.6 meters (2 ft) tall, were said to labor at night while humans slept.
While many consider them mythical, some believe the menehune have historical roots. It’s suggested that the first Tahitian settlers on Kauai encountered earlier inhabitants from the Marquesas. The term manahune, initially used by Tahitians to describe themselves, became derogatory after their defeat by Raiatea warriors, meaning “commoner.” When Tahitians arrived in Hawaii, they allegedly referred to the locals as menehune, a term implying low social status.
Some folklorists argue that the term gained mythical connotations only after European contact. When explorers inquired about structures like fish ponds and aqueducts, they were told the menehune built them. These tales may have merged with European folklore about pixies and brownies, transforming the menehune into a legendary race of nocturnal builders.
