10. Sexual Variations
One of the most bizarre human biological trends is sexual variation. Sexual variation includes the large number of sexual desires and behaviors people experience that are outside what is considered normal. For some reason, people develop bizarre sexual motivations that can’t be explained by science. One of the most common examples is exhibitionism which occurs when people get excitement from exposing themselves in public. Studies have been conducted on the cause of human sexual variation, but little has been determined. Some argue that these variations are acquired by exposure to human contact and behavior, while others say it is strictly biological. It has been determined that most sexual variation occurs in males.
In the 1920′s, Austrian physician Wilhelm Stekel coined the term paraphilia to describe the human arousal to objects, situations, or individuals that are not part of normal stimulation, and will cause the individual distress or serious problems. The American Journal of Psychiatry has defined paraphilia as “recurrent, intense sexually arousing fantasies, sexual urges, or behaviors generally involving non-human objects, humiliation of oneself or one’s partner, children, or non-consenting people.”
It is unknown how many different kinds of paraphilias exist, but one source identifies as many as 549. As you would expect, there is a large scientific and political controversy regarding the continued inclusion of sex-related diagnoses, such as pedophilia, in the Diagnostic and Statistical Manual of Mental Disorders (DSM). Some feel it gives these criminals an excuse for their actions. The list of paraphilias is extremely large and includes some bizarre behavior, such as the attraction to the image of oneself as a vampire, tears, vomit, mucus, menstruation, trees, breast milk, amputees, and feet.
Interesting Fact
Until 1974, homosexuality was included on the list of sex-related diagnosis.
9. Human Behavior and Solar Activity
Alexander Chizhevsky is recognized as the founder of solar-earth research. In the early 20th century, he provided evidence that the Sun could cause terrestrial phenomena. Chizhevsky linked the Earth’s 11-year solar cycle to climate change and mass activity. He proposed that geomagnetic storms were formed during sunspot-related solar flares. Chizhevsky hypothesized that the Sun’s activity could cause plane crashes, epidemics, grasshopper infestations, and damage to electrical equipment. He suggested that people were subconsciously affected by the Sun’s solar cycle.
Chizhevsky wrote that the negative ionization in the atmosphere had a direct impact on human mass excitability. He based his theory on historical evidence and statistics. He proposed that human history is influenced by an eleven year peak in sunspot activity. Chizhevsky investigated the histories of 72 countries from 500 B.C. to 1922, noting the signs of human unrest such as wars, revolutions, riots, expeditions, and migrations, plus the number of humans involved. He determined that 80% of the most significant events occurred during the sunspot maximum.
History shows that humans tend to act on major revolts, revolutions, and civil wars during the solar maximum. In 1996, professor of psychology Suitbert Ertel reported a substantial relationship between solar activity and revolutionary behavior. In his research, Ertel performed statistical analysis on the “Master Index of Violence from Below” (MIVE) for the period 1700-1985 CE.
Multiple studies have been published on the topic of solar flares and human behavior, mainly in Russia. They suggest that solar flares can affect the Central Nervous System (stomach lining), brain activity (including equilibrium), along with human behavior and emotional response. Solar flares can cause people to be nervous, anxious, worrisome, jittery, dizzy, shaky, irritable, lethargic, exhausted, or nauseous. Some people have also reported prolonged head pressure and headaches. Others have reported a sudden onset of insomnia during a solar maximum.
Interesting Fact
From 1948 to 1997, the Institute of North Industrial Ecology Problems in Russia found that geomagnetic activity showed three seasonal peaks that matched an increase in anxiety, depression, bipolar disorder, and suicide in the city of Kirovsk. It has been predicted that the next solar maximum will arrive in February 2013.
8. Left-Handed and Longevity
In humans, handedness is an attribute that shows an unequal distribution of fine motor skills between the left and right hand. The reason for handedness is unknown, but it is clear that right-handed people are more prevalent, showing up in 70-90% of the world population. The percentage of right-handed people is smaller in primitive cultures. Over the last 25 years, a collection of research papers have been published that examine the hypothesis that left-handed people might be at a greater risk for health problems than right-handers.
Some studies have determined that left-handers are regularly behind in language development and more commonly show severe learning difficulties, such as mental retardation. A slightly higher proportion of left-handers have dyslexia or stutter. However, a larger number of left-handers are gifted in music and math. They hold a disadvantage in overall athletic ability and are on average shorter, skinnier, and enter puberty later than right-handers.
Studies show that lefties don’t have as many children and might experience a shorter life expectancy. In 1991, a study was published in the Psychological Bulletin that examined the death of left-handed baseball and cricket players vs. right-handed athletes. The results showed that left-handed athletes died earlier than right-handers. A study published in the medical journal Epidemiology in 2007 found that left-handed women did not live as long as otherwise similar right-handed women. It was reported that they had significantly higher rates of colo-rectal cancer, and heart & blood vessel disease. However, other studies, such as one conducted on Danish twins in 2000, found no difference in death rates of twins in which one was right-handed and other was left-handed.
Some researchers have uncovered a higher frequency of depression, substance abuse, bed wetting, suicide, low birth weight, sleeping disorders, and autoimmune diseases in left-handed people. Lefties have also been reported to be at risk for heart disease. Some articles have connected the rate of premature left-handed death to the fact that in the past schools used to force children to write with their right hand. This caused many people to switch from lefty to righty, which skewed the future data. As for the cause of left-handedness, one theory suggests that a prenatal hormone imbalance may play a role.
Interesting Fact
While no exact set of “leftie genes” have been discovered, people who dominantly use their left hands do have more left-handed family members.
7. Nasal Cycle
The nasal cycle is a biological anomaly that can be found in approximately 80% of the population. In these people, breathing switches from one nostril to the next. Physiologically speaking, most humans have two noses that work together in order to provide constant humidification, filtering, and warming to the body. The passages (nostrils) are divided by a thin wall of cartilage called the septum. These passages meet at the back of your throat, where they take a single tunnel down to your lungs.
In the nasal cycle, which lasts around 2.5 hours on average, erectile tissue will swell up in one nostril, mostly blocking it (not fully). At the same time tissue in the other nostril will shrink, opening it up for breathing. This allows one nostril to do approximately 85% of the breathing at any given time. For a long time, scientists had no idea why the nasal cycle took place, but recent research has uncovered that nostril switching improves a humans sense of smell and helps prevent drying, crusting, and infection of the nose.
A large amount of work has been done to help determine why humans have nasal cycling, but little is written about why it only occurs in 80% of the population. It remains unclear why some humans don’t experience nasal cycling. More interestingly, whatever nostril you are predominately breathing out of at any given time seems to greatly affect your body and brain chemistry.
Interesting Fact
It has been observed that if you lay down on one side of your body, after around 12-15 minutes, the erectile tissue in the nostril on that side of your body will begin to swell until the person changes sides. The switching may be the reason why people tend to switch from one side to the next while sleeping.
6. Anesthesia Awareness
It is not fully understood why certain people are less susceptible to anesthesia than others. For most of the population, anesthesia brings about a loss of consciousness. However, anesthesia awareness does occur in approximately 20,000-40,000 of U.S. surgeries each year. The majority of people who become aware during surgery may feel pressure around the wound, experience hunger, hear conversation, or have difficulty breathing. If anesthesia awareness does occur, some people will feel pain, experience panic, and approximately 70% have lasting symptoms which may be physical or neurological.
Some cases of anesthesia awareness can be explained by a person not receiving enough of a general anesthetic. However, other examples involve patients in the intensive-care unit (ICU) who are paralyzed. There have been many reports of anesthesia awareness occurring while a person is connected to a life support system. Patients who experience full awareness may suffer from severe trauma, especially when they are alerted to problems during the operation. One study has indicated that anesthesia awareness occurs in about 1 or 2 per 1000 patients. To help stop the problem, most hospitals conduct a post operative interview.
A large number of genetic variations may impact how quickly patients clear anesthetics. For one thing, women need a larger dose of anesthetic than men. The reason for this is not fully understood, but may be due to the fact that women drink less alcohol, have different hormones, or that they have a different fat distribution. It has also been reported that childhood obesity, tobacco smoking, and long-term use of certain drugs (alcohol, opiates, or amphetamines) may increase the amount of anesthesia needed.
Interesting Fact
A growing body of research shows that people with red hair need larger doses of anesthesia and often are resistant to local pain blockers like Novocaine. It is believed that redheads are more sensitive to pain because of a mutation in the gene (MC1R) that affects hair color.
5. Mongolian Spot
A Mongolian Spot is a benign congenital birthmark with an irregular shape that is extremely prevalent among Asians, Polynesians, Native Americans, and East Africans. It was discovered by Erwin Bälz, after extensive research of the Mongolians. The most common color of the spot is blue, though it can also be blue-gray, blue-black, or even deep brown. The Mongolian Spot normally disappears three to five years after birth and it is almost always gone by puberty. Rough estimates show that the birthmarks are most prevalent among infants of East Asian groups, but the birthmarks have been recorded in other populations.
Here is a breakdown of the prevalence: European infants 40-45% (highest in Portugal), American Indian 80-85%, Roma 85-90%, East African 90-95%, Polynesians and Micronesians 90%, Caucasian 5-10%. The spot is also highly prevalent in Koreans, African-Americans, Hispanics, East Asians, and Pacific Asians. Children may be born with one or more Mongolian spots, and they are usually located in the small area of the buttocks, or the larger area on the back.
The color of the Mongolian Spot is caused by melanocytes, which are melanin-containing cells. In humans, melanin is the primary determinant of skin color. People whose ancestors lived for long periods of time in the regions of the globe near the equator generally have larger quantities of eumelanin in their skins. The Mongolian Spot is unrelated to gender. In some cases where people are unfamiliar with the spot, it will be mistaken for a bruise and may result in unfounded concerns over child abuse. Not to fear, as the Mongolian Spot is harmless to humans.
Interesting Fact
Mongolian spots and eye color are produced by the same body cells. In regard to eye color, as the child develops melanocytes they slowly begin to produce melanin.
4. Human-Animal Communication
It is not fully understood how animals and humans are able to communicate via non-verbal cues and vocalizations. The interactions between pets and their owners reflect a form of non-spoken verbal dialogue. For example, a dog being scolded does not need to understand human language, but is able to grasp the owner’s biological cues, such as stance, tone of voice, and body language. The communication is two-way, and people can determine the difference between animal noises, such as barks, moans, and meows. If an animal is in distress, it won’t take long for a person to notice.
The role of human-animal communication has been linked to actions people perform when meeting each other, such as the movement of eyebrows, beards and mustaches deep voices, and female breasts. It has been argued that facial gestures such as smiling, grimacing, and eyebrow flashing is universal, and may correspond to signals in other primates. It is thought that human body language includes involuntary responses that can be viewed by animals.
In some cases, people will seek to mimic animals in order to interact with them and gain trust. For example, cats have a mild response where they periodically close their eyes when comfortable. Humans will subconsciously mimic the eye closing in order to establish a tolerant relationship with the cat. People also mimic an animal’s natural patterns of comfort, such as stroking, petting, and rubbing. When a person first meets a dog, the initial response is to put your hand out for them to smell. This allows the animal to feel comfortable and become familiar with you.
Interesting Fact
Some studies have found that people who own pets have healthier hearts, get more exercise, and are less depressed. Pets may also have a significant impact on allergies, asthma, anxiety, social support, and social interactions.
3. Identical Twins
Identical twins are formed when a fertilized egg splits late and divides into two separate individuals. They are always the same sex and have the same genetic makeup, including the same DNA. Identical twins are less common than fraternal twins, who are formed by two separate eggs fertilized by two separate sperms. Identical twins are natural clones and certain parts of their bodies are mirrored. It has been reported that in many cases, one person will be right-handed and the other left-handed. Identical twins have also reported mirrored dental problems and different sized feet.
For the past 100 years identical twins have been used in scientific studies to try and identify a genetic link between medical conditions and DNA. Identical twins serve as a great test subject for nature vs. nurture experiments, as they have the same genes. Recently, a group of identical twins were used to help conclude that fainting in humans has a genetic basis. In the experiment, identical twins were more likely to experience fainting than were pairs of fraternal twins.
In the world of crime, identical twins have been set free in certain cases, due to the inability of authorities to prove 100% that they committed the crime. In one famous case, two men were released after their DNA was linked to a 2009 German heist of $6.8 million worth of jewelry. In regard to physical characteristics, identical twins have some slight differences but, if you face them in profile, their appearance will greatly resemble one other. Modern research shows that the frequency of monozygotic twinning is one in 240 births.
Interesting Fact
Elvis Presley had an identical twin named Jesse Garon Presley that was delivered 35 minutes before him, but died as a stillborn.
2. Chimera
A chimera is an organism or tissue that contains at least two different sets of DNA, most often originating from the fusion of two different zygotes (fertilized eggs). Chimeras are formed from at least four parent cells. As the organism grows, each population of cells keeps its own character, which results in a mixture of tissues. The likelihood of offspring being a chimera is increased via in vitro fertilization. In 1953, a human chimera was reported in the British Medical Journal when a woman was found to have blood containing two different blood types.
In 2002, a British woman named Lydia Fairchild was forced to provide DNA evidence to prove that a man named Jamie Townsend was the father of her children. The test showed that Townsend was the father, but DNA indicated that Fairchild was not the mother. The news shocked Lydia, who was quoted as saying, “I knew that I carried them, and I knew that I delivered them. There was no doubt in my mind.” The police arrested Fairchild, and charged her with fraud and taking part in a surrogacy scam.
Eventually a lawyer for the prosecution found an article in the New England Journal of Medicine about a similar case involving a woman named Karen Keegan, who was a chimera. After multiple DNA tests were carried out, it was found that Lydia Fairchild was a match for her children. The new evidence proved that she carried two different sets of DNA. Fairchild was cleared of all charges, and labeled a chimera by the DNA database.
In biological research, chimeras are artificially produced by selectively transplanting embryonic cells from one organism to another. Many human chimeras show no overt signs of their condition, but others have more obvious physical findings. In 1998, doctors at the University of Edinburgh had a patient that displayed both male and female sexual reproduction organs. Most chimeras show more subtle signs, such as mismatched eyes, or parti-colored hair.
Interesting Fact
In 2007, scientists at the University of Nevada created a sheep whose blood contained 15% human cells and 85% sheep cells. The experiment was an attempt to access the potential for human-animal hybrids that could be used for biopharmaceutical production of cells or organs. The research has been called unethical by some and raised a host of safety issues for scientists. In 2005, the United States enacted the Human Chimera Prohibition Act, which prohibits American citizens from creating chimeras. The act said: “The respect for human dignity and the integrity of the human species may be threatened by chimeras.”
1. Magnetoception
Magnetoception is a sense which allows an animal to detect the Earth’s magnetic field in order to perceive direction, altitude, or location. It has been observed in bacteria, birds, fungi, insects, turtles, dolphins, lobsters, sharks, stingrays, and many other animals. The mechanism for magnetoception is unknown, but a series of hypotheses exist. One involves cryptochromes, which are a class of blue light-sensitive flavoproteins found in plants and animals. Cryptochromes have been observed to detect magnetic fields in a number of species. The second proposed model for magnetoception relies on iron (II, III) oxide or magnetite.
In humans, it has been determined that magnetoception may be possible. Scientists have discovered that magnetic bones exist in the human nose, specifically in the sphenoidal/ethmoid sinuses. Surprisingly, very little research has been published on these bones, which contain deposits of ferric iron. A 2007 study published in the journal Neuroscience put forward the conclusion that low-frequency magnetic fields can produce an evoked response in the brains of human subjects.
In a remarkable discovery, a magnetosensitive protein, cryptochrome-2, has also been found in the human eye. Scientists have conducted a number of experiments with the substance and learned that when the protein is placed in fruit flies, it has the ability to detect magnetic fields. In the experiment, the human cryptochrome-2 protein only worked in the blue range of light. It is unclear whether the cryptochrome-2 protein in humans works the same as in animals.
Despite multiple studies on magnetoception, nobody has been able to identify a sensory receptor that is responsible for the behavior. One problem is that studies tend to rely on magnetic fields that are more powerful than the Earths. It is difficult to determine exactly how the Earth’s magnetic field impacts life, but it has been suggested that animals can navigate by detecting the strength of the field and the angle at which it meets the Earth. Past research has suggested that in addition to helping animals navigate the globe, magnetoception may help with visual spatial perception. “It may aid how animals perceive how objects are in time and space in a way we haven’t thought about before.”
Interesting Fact
The discovery of the cryptochrome-2 protein in the human eye has caused some people to question whether humans have a sixth sense. The protein has been linked to the regulation of circadian rhythms, which are the “body clocks” of humans. This includes the sleep-wake cycle.