What makes humans smarter than other animals? We’ve got a bigger brain, of course. But when it comes to brains, is bigger always better?
Traditionally, scientists have thought that humans’ superior intelligence derived(源于)mostly from the fact that our brains are three times bigger than those of our nearest living relatives, chimpanzees. People even used to believe that because men have slightly larger brains than women that men are smarter.
This, however, is not the truth. Scientists at University College London in the UK have found that brain organization, and not brain size, is the key to the superiority of human intelligence, reported Live Science.
Through millions of years of evolution, our ancestors were constantly pushed to get smarter so that they could meet the demands of new environments. However, holding this growing intelligence in increasingly large brains was not the best choice because bigger brains require more energy to power. “This is when reorganization may come into play, ”said Christophe Soligo, a member of the London research team.
In the study, scientists looked at the brains of 17 species of primates(靈長(zhǎng)目動(dòng)物), including monkeys, apes and humans. They found that in the process of evolution, brains didn’t keep growing as a whole. Certain regions of the brain grew prior to others in response to species’ needs, and in this way they could make the best use of their limited brain space.
For example, when early humans were struggling to survive, the brain region in charge of using tools and finding food grew in size more than other regions. But in modern times, the prefrontal cortex(前額皮質(zhì))—the region in charge of social cognition(認(rèn)知), moral judgments and goal-directed planning—grew more than the rest of the brain.
Think of the brain as a room. If a big room is poorly organized, it doesn’t necessarily store more stuff than a smaller one.
Paul Manger, professor at the University of the Witwatersrand, South Africa, explains this principle using the example of whales. He told Scientific American: “Whales have big brains, absolutely. But if you look at the actual structure of the brain, it’s not very complex. Brain size only matters if the rest of the brain is organized properly. ”
小題1:It has recently been found that humans are smarter than the other animals mainly because
.
| A．they are a species of primates |
| B．they have much larger brains |
| C．their brain structure is more complex |
| D．they were constantly pushed to get smarter |
小題2:According to the article, in recent human evolution,
.
| A．the brain kept growing in size to adapt to new environments |
| B．most regions of the brain didn’t change |
| C．the prefrontal cortex grew more than the rest of the brain |
| D．humans’ brains became increasingly simple so that humans could survive |
小題3:What can we conclude from the article?
| A．Gender makes a difference in intelligence. |
| B．The size of the brain has nothing to do with intelligence. |
| C．Species whose brain is organized properly tend to be smarter. |
| D．Larger brains are usually organized better than smaller ones. |
小題4:The method the writer uses to develop the last paragraph is
.
| A．by presenting research data |
| B．by giving examples |
| C．by making a comparison |
| D．by analyzing cause and effect |
