Saturday, September 05, 2026

Modern humans evolved from an 80-20 mixture of two deep streams


16 May 1998

Dairy by P. D. JAMES

On the day of her seventy-seventh birthday in 1997, proving that it's never too late to begin, acclaimed detective novelist P. D. James wrote her first diary entry - one of many she would pen over the course of twelve months in a concerted effort to 'record just one year that otherwise might be lost.

In 1999, that diary was published for the world to read, offering not ista snapshot of the author's busy life as a septuagenarian but also a collection of vividly recalled memories from her past. She wrote this particular entry on the eighth anniversary of a day spent in Germany with fellow writer Ruth Rendell, months after the fall of the Berlin Wall.


“In both 1986 and 1990 I went from the West into East Berlin. On the first occasion I had to submit to the long unsmiling scrutiny of the frontier police. On the second, Ruth, Don and I were greeted with smiles and the hope that we would have a happy day. Were they the same guards?”




Gina Trapani: The joy of making stuff with a 3D printer. I’ve always been a little 3D printer-curious and this looks like a good resource to start with.



How Baby Boomers Transformed American CuisinePax Culinaria




Retirement Is Dead

MacLeans – Not long ago, while shopping for running shoes at MEC, I asked for help getting sized. As an employee strode up to assist me, I realized I knew him: Steve, a talented writer around my age whose work I’d read for years. I asked how he was doing. His answer: “I’m selling shoes. Steve isn’t the only person I know hustling into their golden years. Recently, I realized that my regular lunches with colleagues of a certain age have turned into pity parties. 

We laugh about how we used to live paycheque to paycheque but finally, through hard work and perseverance, we now live direct deposit to direct deposit. My own agent has struck out with my last three book pitches, and I’ve jumped from the ranks of “up-and-coming” to “failed to fulfill early potential.” In the hopeful imaginings of my twentysomething self, my book jacket bio would list a dozen or so famous titles, and might even include the phrase “divides his time between…”

 Instead, at 63, I’m still living in the little townhouse my wife and I own in North Vancouver, where we raised our two girls. There’s plenty to be grateful for, but I’m no longer wondering how to have a brilliant career. Instead, I’m wondering if I’ll ever be able to stop. At one recent lunch, I suggested a new collective noun: what do you call a group of writers? An anxiety of them. In 2026, that might apply to anyone, middle-aged and older, still beavering away, struggling to figure out if they can possibly retire on the meagre savings they’ve accumulated and facing a late-life precarity that few anticipated. 

I’m terrible with money­—ironic, given that I have a degree in economics. This has become a running joke in my household. I fall prey to all the cognitive errors—temporal discounting, optimism bias. I’m like Michael Scott in an old episode of The Office, meeting with a group of high school students whose college tuition, 10 years earlier, he’d promised to cover:

 “I’m not going to be able to pay for anybody’s tuition,” he admits. “I’m not a millionaire. I thought I would be by the time I was 30, but I wasn’t even close. I thought maybe by the time I was 40, but when I was 40 I had even less money than when I was 30.”


We round up this year’s winners at awards for achievements that ‘first make people laugh and then make them think’



Modern humans evolved from an 80-20 mixture of two deep streams

John Hawks: “Around a decade ago, I was working to understand the deep population history of Africa from genomes of living people. I was just one of many researchers who had begun to notice a shared pattern across genomes worldwide. It looked like everyone living today might have come from a population of hybrids. This was beyond the mixture already known with Neanderthals and Denisovans. For one thing, it was a lot earlier. 

For another, the signs seemed to be everywhere, not just in any particular geographic region. Early statistical methods focused on the differences in ancestry across living human populations, giving them the power to find small fractions of ancestry uniquely in some groups and not others. The 2% Neanderthal ancestry in many populations was first evident because African populations had much less. The story was the same with the roughly 3% Denisovan ancestry in Papua New Guinea, and with a similar small fraction of “ghost ancestry” in some West African groups. 

Still, those methods were likely underestimating the importance of mixture. They are not well-powered to find deeper events that are more widely shared. During the last five years, some studies have opened windows into the deeper history of modern humans in Africa. I covered one of the first studies along these lines back in 2023, a paper by Aaron Ragsdale and collaborators. 

Their results are now joined by subsequent studies using somewhat different methodologies. In broad strokes, it appears that the modern human population evolved from a merger of two ancient groups around 300,000 years ago, roughly 80% from one, and 20% from the other. The uniformity of this signal in all living populations suggests that it was a true formative event. Who were these ancient groups? And why did the descendants of their mingling prove to be greater than either of the parents? These unanswered questions are near the center of my current research…”