Brain size riddle solved as humans exceed evolutionary trend
The largest animals do not have proportionally bigger brains—with humans bucking this trend—a study published in Nature Ecology & Evolution has revealed.
The largest animals do not have proportionally bigger brains—with humans bucking this trend—a study published in Nature Ecology & Evolution has revealed.
Plants & Animals
Jul 8, 2024
5
609
In 1974, on a survey in Hadar in the remote badlands of Ethiopia, U.S. paleoanthropologist Donald Johanson and graduate student Tom Gray found a piece of an elbow joint jutting from the dirt in a gully. It proved to be the ...
Archaeology
Jun 27, 2024
0
124
Researchers have found that nerve cells in the hippocampus region of the brain encode complex information on numerous characteristics of other individuals in the same social group.
Plants & Animals
Jun 27, 2024
0
2
The bottom of the ocean is not hospitable. There is no light; the temperature is freezing cold; and the pressure of all the water above will literally crush you. The animals that live at this depth have developed biophysical ...
Plants & Animals
Jun 27, 2024
1
262
In a recent study led by the University of Liège researchers delved into the intersection of the fields of entrepreneurship and neuroscience, looking specifically at the cognitive flexibility of habitual entrepreneurs—those ...
Economics & Business
Jun 21, 2024
4
74
Magnetic resonance imaging (MRI) is a technique commonly used to explore the brains of sheep. Until now, it had only been performed under general anesthesia, to ensure the animal's immobility. Anesthesia, however, leads to ...
Plants & Animals
Jul 1, 2024
0
60
Schizophrenia is a complicated mental health disorder accompanied by a wide range of symptoms such as hallucinations, impaired cognitive ability, and disorganized speech or behavior. It has been associated with anomalies ...
Bio & Medicine
Jun 27, 2024
0
74
When underwater, humans cannot determine where a sound comes from. Sound travels about five times faster there than on land. That makes directional hearing, or sound localization, nearly impossible because the human brain ...
Plants & Animals
Jun 21, 2024
0
137
About 52,000 years ago, the skinned hide of a Siberian woolly mammoth was exposed to conditions so frigid that it spontaneously freeze-dried, locking its DNA fragments into place.
Paleontology & Fossils
Jul 14, 2024
0
21
Researchers at Tel Aviv University relied on principles of origami, the Japanese art of paper folding, to develop an original and innovative solution for a problem troubling researchers worldwide: positioning sensors inside ...
Biotechnology
Jul 8, 2024
0
89
The brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as jellyfish and starfish have a decentralized nervous system without a brain, while sponges lack any nervous system at all. In vertebrates, the brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing, balance, taste, and smell.
Brains can be extremely complex. The cerebral cortex of the human brain contains roughly 15-33 billion neurons depending on gender and age, linked with up to 10,000 synaptic connections each. Each cubic millimeter of cerebral cortex contains roughly one billion synapses. These neurons communicate with one another by means of long protoplasmic fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body and target them to specific recipient cells.
The most important biological function of the brain is to generate behaviors that promote the welfare of an animal. Brains control behavior either by activating muscles, or by causing secretion of chemicals such as hormones. Even single-celled organisms may be capable of extracting information from the environment and acting in response to it. Sponges, which lack a central nervous system, are capable of coordinated body contractions and even locomotion. In vertebrates, the spinal cord by itself contains neural circuitry capable of generating reflex responses as well as simple motor patterns such as swimming or walking. However, sophisticated control of behavior on the basis of complex sensory input requires the information-integrating capabilities of a centralized brain.
Despite rapid scientific progress, much about how brains work remains a mystery. The operations of individual neurons and synapses are now understood in considerable detail, but the way they cooperate in ensembles of thousands or millions has been very difficult to decipher. Methods of observation such as EEG recording and functional brain imaging tell us that brain operations are highly organized, but these methods do not have the resolution to reveal the activity of individual neurons.
This text uses material from Wikipedia, licensed under CC BY-SA