Parthenogenesis

“Female termites in Japan are reproducing without males” – Newsweek

Parthenogenesis. Fairly common among the social insects. It’s cloning. Upside is that it avoids sexual reproduction, which takes up considerable resources and requires otherwise useless males like yours truly. Downside is that eventually something comes up that your hardwired DNA can’t handle. You’ve parthogenetically opted your DNA out of natural selection. Extinction looms. Which is what happens when selfish genes are way too selfish. Hence most species have sex instead of cloning around.

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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.

DNA testing

So apparently if you get one of those DNA tests, they send you a chart that shows you all the percentages of what ethnicities you are. Then you get to pick out the one that is coolest and be that, as if only that little slice of your genetic heritage made you what you are. But sadly, your Cherokee great great great grandmother didn’t leave you the least bit Cherokee other than a smidgen of Cherokee genes, or your Zulu great great grandfather or the one Irish great grandmother left you neither Zulu nor Irish. Think about it like math–an eighth (your great grandparent) or a sixteenth (your great grandparent) or a 32nd (your great great great grandparent) is just a tiny little bit of you, and the other seven eighths and fifteen sixteenths and 31/32nds long ago washed out most of that inheritance. You are what you are, which is whatever most of you is, all mixed up together, blended, and poured anew into what became you after hopefully a terrific simultaneous orgasm. Your Cherokee great great great grandmother would never even recognize you as one of her own, nor would you take in anyone who said he has 1/32nd of your own genetic background. After all, there are probably hundreds just like him out there, all equally related to that same woman who was born maybe two centuries ago. Which kind of takes the shine off of those DNA tests. It’s just DNA. But it doesn’t mean you have any actually viable connection to any of your distant ancestors other than sharing some of the same genes. And many (if not most or all) of those genes would have mutated during some of those successful couplings between you and your great great great grandmother anyway, so they aren’t even all the same genes. Go back far enough, in fact, and provided you do not come from a carefully maintained line of strict inbreeding (sisters marrying brothers) there will likely not be a single genetic behavioral trait–that is, something that makes your personality distinctly you–remaining that you share directly from your very distant ancestor. The genes behind those traits have all been replaced during successful couplings since then. The raw material of genetics are there, and have always been there, since life began, but the actual genes last only so long. None of us share any of the exact same genes from critters millions of years ago that we have descended from (the synapsids, or mammal like reptiles, for instance), and none of us are passing on specific genetic traits from even several hundred years ago. Maybe your great great great grandfather from Ireland was a writer. And maybe you’re a writer. Did you inherit writing from him? Nope. Lots of people are writers. It just so happens that two people out of the 32 people in the line from your great great great grandparent to you happen to be writers. And two out of thirty-two is almost surely nothing more than coincidence. You might look like him…but then you might look like people you are not directly descended from. After all, that great great great grandfather is only one out of 32 grandparents having sex 16 specific times that gives you the DNA that, all mixed together and randomly mutated, is you. You are much more likely a writer because you had a good English teacher than because one of those 32 great great great grandparents also wrote. Culture trumps genetics in most human endeavors.

Stick with reincarnation. That gets around the whole genetics thing, saves you money on DNA testing, and maybe you slept with Shirley MacLaine in Ancient Egypt. She was a queen. You a slave boy with gumption. Torrid passions two hundred generations ago in the shadows of the pyramids. I mean why not? Though that might make you 1/1280 of yourself in a past life.

Mammal-Like Reptiles

None of my Synapsid ancestors were writers.

 

You, a chicken, and a banana.

(from a comment on a Facebook post I can’t remember)

We share about equal amounts genetic material (I think it 60%) with a fruit fly, a chicken, and a banana. And we are virtually identical genetically–about 99.9%–with all other humans. Though that is genes only, we actually develop at various rates (heterochrony they call that) and turn into the mélange of different looking people you can see all around you. Still, each of us are so identical genetically even if we look sometimes drastically different that we can have sex with each other and create new people who are also 99.9% genetically identical and find partners who look nothing like them and also make babies. It might take a lot of liquor, but it is possible. The important thing is that 99.9% compatibility, which is why we cannot make babies with a fruit fly, a chicken, or a banana. As for the inherited characteristics within that one tenth of one percent that is not identical, the further back you go generationally, the less that any of the genetic material in that one tenth of one per cent have to do with specifically inherited characteristics. For instance, you don’t like music because your great great great grandfather liked music. You probably don’t even have red hair because he had red hair. There are too many variables. Between you and your red headed music loving great great great grandfather are 31 separate couplings by 62 people resulting in 31 births. That’s 31 eggs, 31 sperm cells, and having sex 31 times. We would scarcely be related at all to our own great-great-great grandparents, as we have thirty two of them and what there is of them within our genome would be a mess of scattered bits and pieces coupled fairly randomly with each generation between us and them. Which is good because most of my ancestors were crude peasants with pre-modern hygiene issues. Imagine that family reunion.

Four years of college and all I got was this lousy Darwin Award

(2014)

I wonder how many of the people making smarmy Darwin Award comments understand that there is nothing Darwinian about the Darwin Awards at all? Because Darwin Awards based on strict Darwinian theory would have nothing to do with being stupid. They would be about not having children. Or, childless, having never assisted in the upbringing of blood nephews or nieces who themselves have children. That’s who’d get the Darwin Award. It’s not about brains, it’s about progeny.

Which means, whoops, I win a Darwin Award.

Well, not really. I have some nephews, though I haven’t exactly been an attentive uncle. But same genes, so I am disqualified on a technicality. Had I dropped my brother from a third story window or better yet talked him into joining the priesthood, then I’d scoop up my Darwin Award.

But I didn’t. I have those four nephews. Great kids, all of them. And therein lies the future of my genetic heritage. Or some of it. Me and my brother don’t have exactly the same genes. Same parents, but not the exact same genes in the exact same order. Who knows what bits of junk DNA I have that he doesn’t. And impossible to explain (or even pronounce) heterochronous traits like me being so damn hypermorphotic I can’t find shoes that fit. My brother can find shoes. His kids can find shoes. It’s possible that my huge frame will lie recessed waiting to pop up in some huge baby somewhere in the future. But I think probably not. Something went a little amiss with me. Junk DNA maybe. A Hox gene that went rogue. Odds are that those are a one time only deal. But there’s genetically enough of the same between us, as siblings, to make sure that some of what is in me was also passed on to my brother’s own sons and into their children and on down the line for a few generations (after a few generations it gets so divided up and scrambled it’s not anything recognizably me anymore). And in Darwinian terms shared genes are all you need to succeed. A brother isn’t perfect, gene wise, but he’ll do in a pinch.

Now what about Jose Canseco, butt of a zillion Darwin Award jokes this week for blowing off his own finger? Yeah, that was stupid, blowing off his own finger while cleaning one of his handguns. Really stupid, actually. The middle finger, too, my favorite. But stuff like this doesn’t matter, no matter how dumb it is. What does matter is that Jose Canseco has a daughter. So no Darwin Award for him. Much as you all want to give him one, he doesn’t qualify.

In fact, even if Jose Canseco had no children and shot his middle finger off cleaning a loaded handgun, he still wouldn’t qualify for a Darwin Award. Because Jose Canseco has an identical twin brother, and an identical twin brother, gene wise, is perfect. If that brother has children it’s the same thing as Jose Canseco having children. Identical twins pass on identical genes, or as close as you can get to identical this side of parthenogenesis (i.e., cloning). So even with nine fingers, it’s a Darwinian win/win situation for Jose Canseco. The Jose Cansecos of the world don’t receive Darwin Awards. They hand them out. They call you Double Income No Kid dinks up on stage and hand you a shiny statuette of Charles Darwin. People laugh. You shake Jose’s bandaged hand. He yelps in pain. His identical twin brother leaps up and decks you. You fall backward. The audience, every one of them the spitting image of Jose Canseco, is in hysterics. Then you wake up.

Meanwhile I type this last line with ten fingers and the realization that some fool with nine fingers will have an impact on the coming evolution of the species that I will never have. Because as natural selection goes–and that is the core of Darwin–the winners pass on their genes. And the losers, well, don’t. We’re dead ends. We die, and our individual genetic traits–the blend of our parents that developed, in my case, into me, the guy writing this–will die with us. Disappear. Poof.

Oh well, no use crying over spilled milt.

charlesdarwin2

Charles Darwin had ten children, sparing him the ignominy of a Darwin Award.

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Genetically modified yappy little dogs

(2013)

Before everyone goes bonkers with end of the world scenarios about genetically modified foods, this whole “genetic pollution” concept seems kind of ridiculous to me, because genetic pollution has been occurring for as long as agriculture has existed. Wheat itself is an artificial invention, and corn, and rice, and so are most citrus fruits and a lot of green vegetables. Potatoes were genetically modified. The marijuana that people smoke is genetically modified. It’s just that these were all modified using carefully controlled Mendelian genetics as opposed to altering the genes themselves. Farmers would look for genetic mutations–mutant grains, mutant  tubers, mutant cabbages–and using mutant offspring of those mutants, and then mutant offspring of those mutants, invented wheat, potatoes, Brussels sprouts. When you pick up a bag of variously colored and shaped potatoes, you’re looking at mutant varieties of an original potato. They are mutants in every sense of the word. As mutated as the cast of Freaks, or a Shetland pony, or a two-headed sheep. As mutated as the latest version of the Ebola virus. Something got messed up when the genes duplicated and voila, a purple potato. And in almost every historical case, especially in the grains, these genetically modified plants–these mutants–polluted already existing gene pools that they were capable of inter-breeding with, or simply out competed the native plants, with often ecologically devastating consequences. The verdant hillsides of Southern California in the spring did not exist before the introduction of Spanish farming, herding and viticulture.  It was a completely different landscape then. This sort of man-made genetic pollution goes back ten thousand years at least. These plants altered through Mendelian genetics as opposed to laboratory modifications have had profound impacts from the very beginning  of civilization, even before. Everywhere humanity has introduced agriculture it has fundamentally changed the plant life around it. This is nothing new. The only difference now is that geneticists can go in and selectively alter the chromosomes of plants and bring about specific characteristics artificially rather than letting mutations occur naturally. But keep in mind that naturally occurring mutations can also be tightly controlled. Ask any one who grows hydroponic pot, or raises guppies even. But then if that very process of artificial gene modification scares you, well, nothing I can argue will alter that. You’re just a little freaked out by science, I think.  A lot of people are. It’s nothing new.

I’m not saying that Monsanto should be allowed to lobby themselves all kinds of protections. I’m not saying that Monsanto isn’t an octopus worthy of a Frank Norris novel*. Not at all. But those are issues of corruption, monopolization and anti-small business policies. If that is your issue, well more power to you. But this fear of genetically modified food itself is bizarre when virtually everything you deal with in your daily life that is organically based–i.e., not made of mineral or wild wood–is the result of genetic modification at some point in human history. And I mean everything. Everything you wear, everything you eat, just about everything man-made you touch that is not stone or metal or perhaps carbon-based is somehow a product of genetic engineering. Even the damn cat.

Incidentally, it strikes me as incredibly ironic that the same people who adamantly opposed the Bush Administration’s ban on stem cell research are so opposed to genetic engineering in plants. They are the same thing. Just one is people, the other plants.

Now if you want to see a really creepy display of genetic engineering, creepier than any wheat, get thee down to a dog show. My god, those mutant creatures used to be wolves. Wolves. That yappy little chihuahua? A wolf. Creeps me out every time.
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* In fact, Norris’s 1901 classic The Octopus–a tale of independent wheat farmers struggling against the corrupt and monopolistic Southern Pacific Railroad–was to be the first volume of a trilogy called The Epic of Wheat.