Got a crotchety old guy who kept telling you that youngsters today are getting dumber by the minute (right before he told you to get off his lawn)?
Well, he may be onto something: scientists discovered that our brains are actually shrinking!
The downsizing of human brains is an evolutionary fact that took science writer Kathleen McAuliffe by surprise.
"I said, 'What? I thought it was getting bigger!'" she tells NPR's Jacki Lyden. That was the story up to 20,000 years ago, she learned. Then, the brains of our ancestors reversed course and started getting smaller — and they've been shrinking ever since.
Cro-Magnon man, who lived in Europe 20,000 to 30,000 years ago, had the biggest brains of any human species. In comparison, today's human brain is about 10 percent smaller. It's a chunk of brain matter "roughly equivalent to a tennis ball in size," McAuliffe says.
The experts aren't sure about the implications of this evolutionary trend. Some think it might be a dumbing-down process. One cognitive scientist, David Geary, argues that as human society grows increasingly complex, individuals don't need to be as intelligent in order to survive and reproduce.
I don't know about the science, but it sure explains Jersey Shore! http://www.npr.org/2011/01/02/132591244/our-brains-are-shrinking-are-we-getting-dumber
Photo: Emergency Inflatable Brain from the NeatoShop
Or did I just prove that we are getting dumber?
rather creatures with smaller brains are more likely to work cooperatively and actually succeed in tasks that require more than one person
they pointed to experiments comparing chimpanzees with bonobos (bonobos have smaller brains and more cooperative groups)
while the question of whether or not this cooperative function is akin to intelligence is still debatable, as intelligence in many ways is hard to measure, i would be willing to venture a guess that the people who manage to succeed in a task (civilized humans and bonobos over chimps) are probably the "smarter" ones.
So is brain size really an indication of intelligence.
Anyway, brain size is probably not a very useful proxy for problem-solving ability. More likely, the size and health of the neo-cortex is a better indicator as it probably correlates to higher number of synaptic connections. Even then, if we discover a correlation between a kind of smartness and brain physiology, I doubt it would be a good measure of how successful, productive, motivated, happy, wise, etc. the person will be. Sometimes a hardship with a good set of mentors and friends produces the best results.
Furthermore, we would be forced to conclude that Neanderthals were smarter than homo sapiens. Again, a hypothesis that is generally unsupported by the available evidence.
Here's an alternative hypothesis: brain shrinkage is correlated with agricultural development. Maybe our diets have changed to allow for smaller, more efficient brains. After all, there is certainly evolutionary pressure to have smaller, more efficient organs that consume less energy to perform th same tasks.
I would be curious to know whether the pattern of shrinkage coincided with the development of agriculture as that may play into either or both of our hypotheses.