What is the disadvantage of big brain?
But big brains can be a disadvantage because they are energetically expensive. For big brains to evolve organism must find a way of minimizing energetic costs while maximizing benefits.
Larger brains have low neuron density and low neuron orientation dispersion. That means larger brains do have more neurons, but more importantly they have fewer connections between those neurons and therefore process information more efficiently.
In other words, having a larger brain can increase cognitive ability, but comes at a cost to other parts of the body because it requires more energy (A previous study suggested that cooking and eating meat could have made people smart because it provided humans with enough energy to support a larger brain).
Large, complex brains can process and store a lot of information. That was a big advantage to early humans in their social interactions and encounters with unfamiliar habitats. Over the course of human evolution, brain size tripled.
In healthy volunteers, total brain volume weakly correlates with intelligence, with a correlation value between 0.3 and 0.4 out of a possible 1.0. In other words, brain size accounts for between 9 and 16 percent of the overall variability in general intelligence.
Many habits contribute to poor brain health, but four areas can have the most influence. They are too much sitting, lack of socializing, inadequate sleep, and chronic stress.
(Internet slang, often sarcastic) Very intelligent; genius.
A large brain may aid in decreasing extrinsic mortality. Indeed, large-brained animals generally live longer than short-lived ones [2].
They are: Environmental: Physical challenges — like finding, hunting, or remembering sources of food — provided selection pressure for bigger brains. Social: Interacting with others — either cooperatively or competitively — favored people with brains large enough to anticipate the actions of others.
People with a bigger brain score better on cognitive tests, but the association is extremely small. A bigger brain is, on average, more intelligent, a study of over 13,600 people has found (Nave et al., 2018). The brain scans revealed that people with larger brains do indeed score better on cognitive tests.
Do bigger brains require more energy?
In a 2014 study, anthropologist Christopher W. Kuzawa et al. compared brain scan data across age ranges to calculate how rapidly the brain used glucose. Human brains are large, and consequently need a lot of energy, especially when the brain is growing.
Their argument is simple: brains demand exceptional amounts of energy. Each gram of brain uses up more energy than each gram of body. And bigger brains, which have more neurons, consume more fuel.
Although scientists have not determined an ideal healthy brain size, a brain that is too small (microcephaly) or too big (macrocephaly) can lead to abnormal cognitive development and lifelong challenges. The human brain reaches maximum size around a person's early 20s, Thompson said.
Macrocephaly is often present at birth. The cause can be harmless if you have other family members with larger heads and there aren't any other signs or symptoms present. But macrocephaly can also be a sign of a serious condition.