Attention Deficit in Teenage Boys: Who Would’ve Guessed?

A Brief Background

Attention Deficit Hyperactivity Disorder, also known as ADHD, is one of the most prevalent psychiatric diseases in childhood adolescence across the globe (Polanczyk et al, 2005). Children with ADHD find difficulties with their inattention, hyperactivity, and/or inability to control their impulses. These lifelong symptoms are caused by numerous neurotransmitter systems and various brain functions. Prenatal conditions such as low birth weight, prematurity, and prenatal exposure to alcohol and/or other toxins are external risk factors. The socioemotional environment during postnatal development and food constituents/micronutrients can also contribute to ADHD symptom severity (Capusan et al, 2005). There are many risk factors in early development associated with ADHD, such as delivery method, gestational age, type of feeding, maternal health, and early-life stressors, all of which have an effect on the gut microbiota of patients with ADHD. Continue reading “Attention Deficit in Teenage Boys: Who Would’ve Guessed?”

Aggressive Tendencies Not All That Bad


Three Spined Stickleback (Gasterosteus aculeatus) males in territorial dispute by Warren Photography.

Behavior is Heritable?

Personality and behavior are not often thought of as heritable, meaning that those traits aren’t usually passed down from parents to offspring. The two are usually thought to be a product of the environment in which an organism lives. Why then are certain organisms able to exhibit certain personality or behavioral traits regardless of their environment? Humans have this ability, depending on the environment most of the time, they adapt to where they are at in order to be most successful. The same could be said for any organism, they are trying too obtain the highest fitness and reproductive rates. Some traits such as levels of aggression, can determine whether an individual survives or is eaten by a predator. If aggressiveness is a positive trait for survival and reproductive success, how is it passed down to future generations? Even though attitude is not necessarily thought of as a gene, it is possible that the combination of many genes and environment an organism lives in can play a factor in behavioral tendencies. Natural selection works in a fascinating way that allows for beneficial alleles, genes and mutations to increase in frequency as time goes on. If it is seen that an allele or trait is beneficial, females will look for males with that particular trait (sexual selection), so that their offspring have a better chance of surviving and reproducing in the future. This extraordinary phenomena can be seen in many different organisms, such as humans, elephants and even fish. Continue reading “Aggressive Tendencies Not All That Bad”

Inheritance of personality: How much do genes matter?

Picture of meerkats
Extremely social animals like meerkats may benefit from specializing in particular social roles to avoid social conflict, which could create distinct personalities that may persist through time (Carter et al. 2014) Photo credit: © anekoho / Fotolia

Personality. All individuals have one. Yet, what actually contributes to individuality? Although seemingly simple, personality frustrates evolutionary biologists due to its complex and convoluted nature. It is well established that personality can have important evolutionary implications (1, 2, 3, 4, 5), but determining a method to test the genetic underpinnings of personality has proven difficult. Continue reading “Inheritance of personality: How much do genes matter?”