Heads Up: Problem Solving Pushed Bright Primates toward Bigger Brains. (This Week)
Bower, B., Science News
Progressively larger brains evolved in primates of all stripes, not just humans. We can thank a common capacity for solving a broad range of problems, from coordinating social alliances to inventing tools, according to a new study.
This conclusion challenges a popular theory that big, smart brains arose primarily because they afforded advantages when it came to negotiating complex social situations during human evolution.
"The ability to learn from others, invent new behaviors, and use tools may have [also] played pivotal roles in primate-brain evolution," say Simon M. Reader of McGill University in Montreal and Kevin N. Laland of the University of Cambridge in England. In an upcoming report in the Proceedings of the National Academy of Sciences, the two zoologists chronicle links between an array of intelligent behaviors and enhanced brain size in primates.
Reader and Laland examined approximately 1,000 scientific studies of behavior in 116 of the world's 203 known primate species. They identified 553 instances of animals discovering new solutions to survival-related problems, 445 observations of individuals learning skills and acquiring information from others, and 607 episodes of tool use.
The researchers then consulted previously obtained data on brain size relative to body size in different primates. In particular, they focused on the volume of the structures that make up what scientists call the executive brain, a frontal region thought to be crucial for complex thinking. …