Heritability, amount of phenotypic (observable) variation in a population that is attributable to individual genetic differences. Heritability, in a general sense, is the ratio of variation due to differences between genotypes to the total phenotypic variation for a character or trait in a population.

Natural selection is a process that causes heritable traits that are helpful for survival and reproduction to become more common, and harmful traits to become more rare. This occurs because organisms with advantageous traits pass on more copies of these heritable traits to the next generation.

This affects the rate of evolution and can be used to predict the evolutionary trajectory of a population. Higher heritability means the trait evolves faster; fewer generations are required for the trait to increase to the same degree as a trait with lower heritability.

Reciprocally, traits that appear to be completely invariant in a species may nevertheless evolve. One of the most important findings in evolutionary genetics has been the discovery of substantial genetic variation underlying characters that show no morphological variation!

Traits can appear in families for many reasons in addition to genetics, such as similarities in lifestyle and environment. For example, the language that is spoken tends to be shared in families, but it has no genetic contribution and so is not heritable.

A high heritability, close to 1, indicates that genetics explain a lot of the variation in a trait between different people; a low heritability, near zero, indicates that most of the variation is not genetic.

Given its definition as a ratio of variance components, the value of heritability always lies between 0 and 1. For instance, for height in humans, narrow-sense heritability is approximately 0.8 (Macgregor et al., 2006).

Since heritability is the proportion of phenotypic variation of a trait that can be attributed to genetic variation (Boomsma et al. 2002), reducing environmental and residual components will give an increase of the heritability.

The Genetic Basis for Introversion It also determines many personality traits, such as your tendency toward introversion or extroversion. This correlation is so strong that Laney says children show their introversion/extroversion tendency from the moment they’re born.

Introverts don’t take risks Fears and desires are a completely different distinction from extroversion and introversion. “[These labels] convey misinformation and can cause rumors to spread about these personality characteristics that are unfounded,” Dr. Fraga says.

An introvert is a person with qualities of a personality type known as introversion, which means that they feel more comfortable focusing on their inner thoughts and ideas, rather than what’s happening externally. They enjoy spending time with just one or two people, rather than large groups or crowds.

If you’re a person who feels equally fulfilled whether you’re out in a crowd or at home alone reading a book, you might be an ambivert. Ambiverts have lots of great traits. They’re able to be flexible in a variety of situations, often knowing when to talk and when to listen.

Am I an Ambivert or Omnivert? An Ambivert is someone whose overall behaviour is between introversion or extroversion. An Omnivert is someone who can be the extremes of either at different times.

These people (a.k.a., the vast majority of us) are called ambiverts, who have both introverted and extroverted tendencies. The direction ambiverts lean toward varies greatly, depending on the situation. Ambiverts have a distinct advantage over true introverts and extroverts.

Extroverts tend to be quite outgoing and talkative. They enjoy spending time with other people, and feel energized in social situations. Oftentimes, extroverts like being the focus of attention. Introverts tend to enjoy solitude and spending quiet time alone.

To be clear, both introverts and extroverts can struggle with social anxiety, and not every introvert is anxious. Introversion is a temperament, meaning introverts were likely born that way and will stay introverts for life (although research shows we do grow and change). Social anxiety, in contrast, is treatable.

But it takes a little more explanation to understand why, according to Myers-Briggs personality theory, ambiverts don’t exist but we all have some Introverted and some Extraverted preferences. Personality preferences, like Extraversion and Introversion, are often compared to being right or left-handed.

“Because they naturally engage in a flexible pattern of talking and listening, ambiverts are likely to express sufficient assertiveness and enthusiasm to persuade and close a sale but are more inclined to listen to customers’ interests and less vulnerable to appearing too excited or overconfident.”

Extroverts are often described as the life of the party. Their outgoing, vibrant nature draws people to them, and they have a hard time turning away the attention. They thrive off the interaction. On the opposite side are introverts. These people are typically described as more reserved.

People with high extroversion tend to relate well to others, and are often well-liked in their teams and offices. They form quick and easy friendships, and their outgoing nature leads to effective group-work.

On the positive side, extroverts are often described as talkative, sociable, action-oriented, enthusiastic, friendly, and out-going. On the negative side, they are sometimes described as attention-seeking, easily distracted, and unable to spend time alone.

An introvert is often thought of as a quiet, reserved, and thoughtful individual. (The term “extrovert” is now used more commonly than “extravert.”) Introverts, his basic definition said, prefer minimally stimulating environments, and they need time alone to recharge. Extroverts refuel by being with others.

All photos courtesy of the members.

1. Get Out of Your Head.
2. Be Brave and Push Yourself.
3. Learn to Tell Stories.
4. Practice and Plan.
5. Avoid the Lone Ranger Syndrome.
6. Be Yourself, Get to Know Others, and Bend as Needed.
7. Stop Labeling Yourself as an Introvert.
8. Let Active Listening Be a Positive Thing.

: doing things or tending to do things suddenly and without careful thought : acting or tending to act on impulse. : done suddenly and without planning : resulting from a sudden impulse. See the full definition for impulsive in the English Language Learners Dictionary. impulsive.