Three answers
And while I'm in the usual point-missing mood, here's another easily solved mystery.

Via MindMatters as usual, a puzzle about brain size. Why has the size of brains been gradually shrinking for 40k years while (supposedly) our intellect has been expanding?

Three plausible answers.

1. The broad logical answer is that brain size is an irrelevant variable, or nearly irrelevant. There are some hard limits, which are easy to locate. Crows and elephants and whales are in the same range of intelligence despite hugely different brain sizes. But ants and wasps are NOT in the same range as crows, and bacteria are not in the same range as ants.

2. Engineering provides a more subtle answer for the more subtle question of a 10% shrinkage in one species. Microcomputers are faster than 1957 mainframes because the WIRES ARE SHORTER. The 1957 mainframe had the same calculating and decision power as a modern CPU. The modern version can handle more decisions per second because the electrons only have to travel a tiny fraction of an inch instead of several feet. In an analog system like the brain, shorter wires and smaller coils allow higher frequency resonances. Resonance is thought.

When the associative fibers between cortex and brainstem are 10% shorter, the RESONANT WAVES can be 10% higher in frequency, getting more processing done in each second.





Actually I prefer Door Number 3:

3. Nature starts with the most complex and then simplifies. Evolution is subtractive. We are dumber than Neanderthals. We've built up the materials and methods for superior technology over thousands of years, and as the technology takes over more of our brain function, we LOSE our brain function. Our brains are smaller because we've offshored and outsourced part of their skills.

Labels: Answered better than asked, skill-estate

  ¶ 9:10 AM