They will attract each other together
The word extraversion is popularized by Carl Jung and defined it as "an attitude type characterized by concentration of interest on the external object (focuses on the outside world). Contemporary psychologists classified the dimensions of personality into five, which is referred to as the "BIG 5" personality traits. The BIG 5 are broad categories personality traits and though there are significant body of literature supporting this five-factor model personality, researches do not always agree on the exact labels for each. It will be helpful to remember the word OCEAN as an acronym for these "BIG 5" personality traits: Openness, Conscientiousness, Extraversion, Agreeableness and Neuroticism. Extraversion is one of the "BIG 5" personality traits an is characterized by excitability, sociability, talkativeness, assertiveness and high amount of emotional expressiveness. Extroverts are outgoing and gain energy in social situation. They tend to: enjoy being the center of attention because they get energized when they are around people, like to start conversations, enjoy meeting new people, have a wide social circle of friends and acquaintances because they find it easy to make friends and say things before they think about them. A published journal by Stephanie M. van den Berg, et al., entitled Harmonization of Neuroticism and Extraversion phenotypes across inventories and cohorts in the Genetic Personality Consortium: an application of Item Response Theory (IRT), studied on the heritability of extraversion in twins. The IRT-based scores for Neuroticism and extraversion were heritable, with 48 and 49% respectively, based on the meta-analysis of six twin cohorts with a significant part of the heritability due to non-additive genetic factors. For extraversion particularly, these genetic factors differ across sexes. So whether identical or fraternal, it correlates around 49-50% but will differ only across sexes, that is, whether male or female.
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In theory, the part of the brain that is responsible for the sleep wake cycle is the hypothalamus; specifically, the ventrolateral preoptic nucleus of the hypothalamus. In the image, the location of the hypothalamus is pointed by the green square.
Answer: a. increased energy efficiency
Explanation: