Do we believe in evolution? Are we products of the environment that surrounds us? Darwin believed. The British Broadcasting Corporation (BBC) recently reported that anthropologists have concluded that "around 100 generations ago, our ancestors had brains that were larger than our own." The human brain is shrinking. The volume is not some inconsequential millimeter here or there either, but "the lost volume, on average, would be roughly equivalent to that of four ping pong balls." according to on anthropologist.
This loss has occurred beginning "just 3,000 years ago." In 2022, that might seem a bit scary. The anthropologists noted that we evolved to "agriculture . . . (as a societal norm) between 10,000 and 5,000 years ago," in a significant sense, "although there is some evidence that plant cultivation may have started as early as 23,000 years ago." We have long been farmers, despite which I can never seem to keep a plant alive and thriving.
Notably, "the first writing appeared" somewhat coincidentally, around 3,400 BC. Note that, with writing came the beginning of brain shrinkage. There has also been shrinkage in our body size, "but not enough to account for our reduction in brain volume." The scientists cited by the BBC concede that the direct cause and effect are not known. However, through study of "the humble ant," they are propounding a suggestion.
Of course, ants are not something to which we might all look for explanation or inspiration. Ant brains are very rudimentary, very small and orders of magnitude simpler than ours in terms of neurons and function. But, there is the suggestion that living in a complex society, in which there is specialization and "division of labor," might lead to organisms needing less brain capacity and thus shrinkage. In short, "cognitive capabilities get divided up and distributed among many members of the group, who have various roles to play." We don's all have to remember how to shoe a horse or fix a machine, or balance a ledger. So, we don't need the brain capacity for all, but merely for our own focus.
The anthropologists question whether we might reach "a threshold of population size, a threshold in which individuals were sharing information and externalizing information in the brains of others?" Or, perhaps, externalizing information in written references like books, and the Internet, and even this lowly blog. With the advent of external memorialization, might we be affording our brains some opportunity to atrophy? With the world at our fingertips, a computer in every pocket, and knowledge (or the opposite) increasingly accessible, might our brains be responding?
The good news is that brain shrinkage does not represent us becoming "stupider." Some believe that it might lead to "subtle differences across a large population," but not a generalized intellectual shrinkage in individuals. Studies have indicated "that having a bigger brain was, on average, associated with doing slightly better on IQ tests," but there is no generalized proof of cause and effect. In fact some studies regarding gender and brain size absolutely deny and defeat correlation of size and function.
The world is changing. I recently noted the evidence that I am getting cooler (we all are, just a bit). See Changes, Getting Cooler (November 2020). We are evolving. And, this evidence suggests that our specialization of tasks and processes, added to our ability to externalize data may be affecting us and our posterity. However, in just one generation (not the 30 that are discussed by the BBC), I have witnessed a great deal of externalization. When I was a kid and even a young adult, we used to remember things like phone numbers. I knew the office numbers of dozens of lawyers, doctors, adjusters, and more back in the day. We remembered them because we used them, used them because we needed to, and when we didn't we looked them up in books, large and small.
That kind of data is now externalized completely. My old friend Horace Middlemier, III recently conveyed a story in which he was stranded with a broken-down car and had to spend an extra day at a lake rental. I asked why he did not call me for help and he said simply "I don't know your phone number," and "my phone was dead." Though that sounds like a convenient excuse for another day in the sun, I reflected and realized I do not even know my parents' or children's phone numbers. If I lost my phone, I would be without a clue on how to contact anyone. And, to be honest, that does not sound so bad perhaps, particularly if I could find myself thus stranded in some quiet and scenic locale.
There is much convenience from our tools and technology, but in the process of reliance perhaps we lose knowledge. And with that evolution, perhaps our future and progeny do also.
