Half a Brain is All I Need

(Part of) our brain is in the Cloud

In 2018 I tried to buy the maximum memory of 512GB for a new iPhone XS Max but had to settle for the 256GB model in inventory.

Five years later the XS Max is only 40% filled. I didn't create as many files or download as many apps as I thought I would, but the main reason the extra storage is unnecessary is that I've transferred most of the files to Apple's iCloud. (Our subscription costs $9.99 per month for 2TB, which can be shared among the family.)

The larger iPhone capacity was unnecessary because some of the tasks could be offloaded to Apple's network.

It turns out that there's a biological parallel: the human brain has shrunk over the past 5,000 years. [bold added]

But a growing body of evidence suggests our brains recently changed in an unexpected way: They diminished in size sometime following the end of the last Ice Age.

“Most people think of brain evolution happening in this linear way. It grows, plateaus and stops,” said Jeremy DeSilva, a professor of paleoanthropology at Dartmouth College. “But we’ve lost brain tissue equal to the volume of a lime—it isn’t a tiny little sliver we’re talking about.”

The precise timing of that post-Ice Age brain shrink has remained a mystery until now. A group of researchers led by DeSilva used a mixture of fossil and modern specimen data to pinpoint that this loss of gray matter happened between 3,000 to 5,000 years ago, according to research published in June in the journal Frontiers in Ecology and Evolution.

Many anthropologists had initially posited the changes coincided with the advent of agricultural practices around 10,000 years ago, and a global shift away from hunting and gathering.

The more-recent dates from DeSilva’s group point to booming eras for ancient civilizations in North Africa, the Middle East and South America—complex societies that they think may have played a role in the shrinkage.

They hypothesized that human societies got so cooperatively organized in the past 3,000 years that we began relying on what researchers call collective intelligence.

“It is the idea that a group of people is smarter than the smartest person in the group,” said James Traniello, a biology professor at Boston University and one of DeSilva’s co-authors. “So basically, if you live in a group, you solve problems more rapidly, more efficiently and more accurately than what’s possible for any individual.”

Traniello said the inspiration for applying this idea to why human brains may have shrunk came from “ultrasocial” insects such as ants. Ants form highly cooperative societies in which division of labor has favored smaller-brained individuals due to an advanced level of social organization.

The researchers suggested that perhaps our need to maintain a large brain—to keep track of information about food, social relationships, predators and our environment—has also relaxed in the past few millennia because we could store information externally in other members of our social circles, towns and groups.

We don't have to hunt to survive, so it's logical that our senses--and the related parts of the brain--don't have to be as acute as they once were. Nor do we have to store as much knowledge in our head when we can rely on other people, books, and the World Wide Web. The extra brain cells are not needed.

However, I'm still going to try to get the 1TB version of the iPhone 15 Pro Max.