Bricksscience.com is part of the brickwahl.com universe that also includes brickspicks.com (music and culture), bricksbrain.com (cognition, perception and my epilepsy), brickspolitics.com and brickshistory.com.

Advertisements

Quirks of fate

It seems that 70,000 years ago the global population of homo sapiens was reduced to less than 26,000. Apparently they teased out that bit of info through some genetic analysis. As humans were by then in Africa and across much of Eurasia, that means we were very sparse on the ground. All seven billion of us spring from remarkably small numbers of people. Indeed, it’s been suggested that as few as seventy individuals came across the Bering Strait land bridge to eventually people the entire western hemisphere. We’ve had more than seventy people in our pad at parties. I never thought of them as a genome before. Well, I did once and got my face slapped. But I digress.

A million or so years ago our antecessor species Homo erectus seems in the genetic analyses (if I knew how they do this I’d tell you) to have been reduced to less than a thousand individuals….and remained like that on the razor’s edge of extinction for maybe a hundred thousand years. Everything we are was dependent on a population the size of a very small town or a medium sized high school or the fans of failing rock band in a big, mostly empty concert hall. Somewhere in that tiny population was some of us, genetically. Whatever genetic factors helped members of that population survive a particularly brutal hundred thousand years of Darwinian natural selection (as other related human species went extinct) lies deep in our own genome. And when 70,000 years ago something happened globally that reduced Homo sapiens to less than 25,000 individuals, we survived while the last of Homo erectus died out, unable to survive what it had once survived for a hundred thousand years. No one ever said natural selection was fair. It’s anything but. The fossil record is full of species of humans and proto-humans no longer here. Fleshed out by talented artists, they gaze at us with all the pathos of a Rembrandt. You can sense their intelligence and emotions. Then you look at the skulls again, bare and ancient and hopelessly extinct. There but for quirks of fate, is us.

There are a hundred trillion bacteria in your body as you read this, and a bunch of these guys in those bacteria.

The surface it is standing on would be, I assume, the interior of the exterior of a bacterium, being that bacteriophage viruses invade and then replicate within bacteria, taking proteins from the bacteria to create copies of itself. Sounds creepy, though the influenza virus does the exact same thing, using our cells instead of a single cell bacterium. From a virus’s unthinking and barely even alive POV, a cell is a cell. What matters is the proteins in the cell, without which there can be no baby viruses.

Dead owls

I suspect that the exponential increase in the pet cat population led to the exponential increase in urban and suburban coyotes which led to the decrease in the time cats spend outdoors which has caused the exponential increase in the urban and suburban brown rat population which has caused an increase in the amount of rat poison used which has dramatically increased the number of dead and dying rats which has led to the increased mortality in owls I read about today.

They did not have a flu shot in 1918

The 1918 influenza epidemic infected half a billion people out of global population of 1.8 billion. Somewhere from fifty to one hundred million of those people died. Nearly everyone killed by the flu was under 65, with most being between 20 and 40, in whom the body’s immune system’s reaction was so severe that lung tissue was reduced to a thick mass and the victims drowned in their own phlegm. A perfectly healthy young person could fall sick in the morning and be dead that night, as a strong  immune system made the disease all the more deadly.

There was no flu shot in 1918, which means people in 1918 were just as vulnerable as people who didn’t get the shot this year. Fortunately the flu this year is vastly less deadly, and will probably only kill a few tens of thousands world wide. It’s a roll of the dice every year, but at some point  a flu virus will evolve that drops people like flies. Could be next year, could be in a hundred years. If you get the shot you lessen the odds of dying a rather quick and ghastly death. It’s up to you.

Hominin hominin hominin

Many years ago I was reading Donald Johanson’s Lucy: The Beginnings of Humankind and watching The Honeymooners at the same time. Bad idea. This one note bit popped into my head and I have not been able to shake it since. Three decades later I asked myself what would Richard Dawkins do? So I meme the thing.

Why so excited Ralphie boy, what did you find there, the jaw of a baboon?
N-N-N-Norton, I found a homina homina homina.
Calm down, Ralph, it looks like the jaw of a Pliocene baboon to me.
Homina homina homina.
But let me take a closer look.
Homina homina homina.
You’re right, Ralph, it’s not a baboon, not with these incisors.
Homina homina homina.
Good lord, Ralph, you’ve found a homina homina homina.
Homina homina homina.
Hi Ed, Hi Ralph, Alice home? Just what are you two so excited about?
Homina homina homina.
Homina homina homina.
Let me see that jaw. Why it’s, it’s a homina homina homina.
Homina homina homina.
Homina homina homina.
Hi Ralph, Hi Ed, Hi Trixie, what are you three babbling about?
Homina homina homina.
Homina homina homina.
Homina homina homina.
Let me see then. Why it’s a hominin!
Hominin hominin hominin.
Hominin hominin hominin.
Hominin hominin hominin.
I’ll call it Lucy.
Ralph!
I’ll call it Alice then.

Human extinction, or not.

(This was a Twitter thread)

There are very few examples on planet in human history where human societies or civilizations completely vanished. Even in times of catastrophic change–creation of the Sahara, 90% fatal pandemics in Amazon, volcanic devastation–human beings have stayed, even if reduced from large scale societies to hunter gatherer bands. Society changes, civilizations collapse, but the species does not go extinct. Indeed, our very evolution has been achieved by dealing with continuous stress and change including population crashes to as few as one thousand or less individuals for the entire species for as long as 100,000 years. We survived, evolved and thrived under extraordinary pressures that would have driven most species–indeed all other hominid species–to extinction. We are extraordinarily adaptable and virtually everything about us is designed to allow us to survive under extremely stressful conditions. That’s why we are here and not a single other human species remains. Society, culture, civilization are all dispensable, it is our extended family that is the default unit that allows Homo sapiens to survive almost anywhere under any conditions. The point of this is that no matter how severe climate change is, no matter if civilization collapses and our numbers are reduced to 1/100,000,000th of today’s population, Homo sapiens will survive. It would take something much more drastic–a giant asteroid, perhaps, or a nuclear war involving thousand of warheads–to completely annihilate the species forever. Both of which are possible, of course. But we will survive even the worst case global warming. It will not be comfortable, the impact on nearly all the world’s ecosystems will be devastating, and it’s hard to imagine a more dystopian future, but it will be livable for just enough of us to keep the genome going.