Skip to main content

We are still evolving

I was having a discussion with a friend recently about the influence of genetics on mental gifts. I was saying that my grandmother used to track various talents through the family. So and so got the music, someone else got the math, and so on.

To my surprise, my friend said that genetics played no part in mental gifts, that there was no such thing as music or math gene. I tried to make it clear that I wasn't saying there was a single gene for either of these, but there were clusters of genetic predispositions that quickened interest and skills, and even attitudes. He maintained that it was all due to early experience and environment.

On reflection, it does still seem to me that such gifts run in families, and although environment surely plays a part, it doesn't seem like much of a stretch to say that genetics does, too. If genetics can affect a pancreas or heart, why couldn't it also influence a brain?

It interested me, so I've been doing some reading. Today I finished "the 10,000 Year Explosion: how civilization accelerated human evolution," by Gregory Cochran and Henry Harpending. The thesis was one I hadn't seen before. We know that about 40,000 years ago, there was a burst of creative energy, the sudden appearance of cave art, tool-making, apparent funeral rites, and so on. According to the authors, this was the beginning of a spurt of evolutionary change that continues.

Among the things they cite is the architecture of alleles, which reveal how recently changes have happened. Skin and eye color variations have all happened within the past 10,000 years! (Before then, people were dark-skinned and brown eyed.) Other changes, like the adoption of lactase tolerance, are even more recent. In the second to last chapter, the authors detail how the Ashkenazi Jews, through genetic isolation and selection from roughly 800 AD to 1700 AD , wound up averaging just a little smarter than the rest of the world, with significant results in the world of scientific achievement, among other things.

The book details many stories of how genetic traits appear, and how rapidly they spread, or die out. The whole thing was new to me. Like most folks, I thought that humans have been about the same since we killed off the Neanderthals.

Something that stays with me is the story of how someone tried to domestic a fox. By just choosing the tamest of the litter, and breeding them together, he wound up with a tame fox in just a few generations. The surprising piece was that the physical appearance and other behaviors changed, too. The head got rounder. The ears got floppier. They exhibited, into adulthood, behavior that was more like fox pops. It's a recapitulation of the domestication of dogs.

If changing our diet (adopting dairy farming, or moving to grains rather than nuts and berries) can quickly affect changes in our physiology, imagine now what exposure to technology may be doing.

The point: human evolution isn't over yet. It may be picking up speed.

Comments

Lynne said…
This is very fascinating! I'm going to read this book!
Jamie said…
Thanks, Lynne. It's a quick read, but I love running across new ideas.

Popular posts from this blog

Uncle Bobby's Wedding

Recently, a library patron challenged (urged a reconsideration of the ownership or placement of) a book called "Uncle Bobby's Wedding." Honestly, I hadn't even heard of it until that complaint. But I did read the book, and responded to the patron, who challenged the item through email and requested that I respond online (not via snail-mail) about her concerns. I suspect the book will get a lot of challenges in 2008-2009. So I offer my response, purging the patron's name, for other librarians. Uncle Bobby's wedding June 27, 2008 Dear Ms. Patron: Thank you for working with my assistant to allow me to fit your concerns about “Uncle Bobby's Wedding,” by Sarah S. Brannen, into our “reconsideration” process. I have been assured that you have received and viewed our relevant policies: the Library Bill of Rights, the Freedom to Read, Free Access to Libraries for Minors, the Freedom to View, and our Reconsideration Policy. The intent of providing all tha...

Installing Linux on a 2011 Macbook Pro

I had two MacBook Pros, both 13" models from late 2011. One had 4 gigs of RAM, and the other 8. Both of them were intolerably slow. In the first case, I wound up installing CleanMyMac , which did arcane things to various files, and put up alerts to warn me about disappearing memory. But it made the machine useable again, albeit not exactly speedy. I changed some habits: Safari as browser rather than Firefox or Chrome. I tried to keep tabs down to four or five. The second Mac had bigger problems. Its charger was shot, but even with that replaced, the battery tapped out at 75%. More importantly, the whole disk had been wiped, which meant that it wouldn't boot. Recently, I had downloaded a couple of Linux distributions ("distros") on USB drives. Elementary OS 5.1 (Hera) was reputed to be a lightweight, beautiful distro that shared some aesthetics with the Mac OS. So I thought I'd give it a try. Ahead of time, I tried to read up on how difficult it might be to...

What Is Leadership?

My partner and I just finished co-teaching a leadership institute for librarians in the Western States. But I keep thinking about it. Some people, I know, think leadership is all about power. But I always wonder: power to do what? To make or to break? Over my 40-odd years of administrative experience — and some of them have been very odd indeed — I’ve boiled my idea of leadership down to three things. Know thyself . That is, have a relatively clear-eyed assessment of your strengths. Build on those strengths. But also learn how to recognize in other people the strengths that you do not have. Play well with others . Leadership begins with listening and paying attention. Then it moves into emotional intelligence — the ability to read and respond appropriately to human communication. The good news is that emotional intelligence is a skill set. It can be learned. The bad news is that a lot of people don’t bother. Make it better . There’s no point in leadership that makes things worse. Good ...