China’s One-Child Policy, now in its fourth decade, has achieved its goal of controlling population growth in the world’s most populous country, but it has also created major age and gender imbalances in the process.
In addition to sweeping social and economic instability, the policy has
proven problematic on an individual level. An entire generation of Chinese has essentially grown up spoiled and without siblings. The resulting shift in social behavior is often referred to as the “little emperor effect,” and researchers have now quantified its impact in a study published this week in Science.
Selfishness is good for us—thinking “me (and my relatives) first” lets humans ensure their survival and that of their genes. But generosity can be good, too; it binds humans into safe communities. So if both behaviors are beneficial, which one dominates? A new Nature paper suggests that it all comes down to timing: when we have to make a fast decision, we act more generously than when we have time to think about our choices.
The healthy little brown bats roosting close to the bat
with white-nose syndrome risk infection with the fungus
The deadly fungus that causes white-nose syndrome is sweeping through North American bat populations, and little brown bats are adapting their behavior to avoid it. Although these bats typically clump together in large groups, they are now spreading out to roost separately, a change in behavior that may be helping the bat populations rebound. So what does a bat-killing fungus have to do with human prejudice? The bats’ trick of splitting up to survive contagion may also have led humans to divide into tribes and respond hostilely to members of different, potentially diseased groups.
In a post on Scientific American’s Guest Blog, biologist Rob Dunn writes about the link between infectious diseases and human prejudice.
A new model of crowd behavior uses simple visual rules.
What’s the News: When crowds go wrong, they go really wrong—more than 300 people died in a stampede in Cambodia last year during a festival, and hundreds more have been crushed to death in periodic disasters near the Muslim holy city of Mecca. A major flaw of computational models describing how people behave in crowds is that they are often too simplistic or too specific to a situation to explain both normal and disastrous behavior. A new model manages to recreate both types of behavior, working from two basic visual rules: (1) each person will move in the least crowded direction in their line of sight, and (2) they will adjust their speed to maintain a safe distance from visible obstacles.
“This work is an extremely important step in pulling together our fragmented understanding,” says behavioral biologist Iain Couzin, who was not involved in the study (via ScienceNOW). “We’re now approaching a sort of unified understanding of human behavior in crowds.”