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Cake day: June 19th, 2023

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  • That’s not wrong at all, but there is a much more recent Adam and Eve - an actual anatomically modern human woman and man that all of us are descended from (although, again, they probably lived about 100,000 years apart - I.e. they weren’t a couple)

    It should also be stressed that I’m not saying that at one point there was only one woman alive or one man alive.

    Mitochondrial DNA isn’t like the usual inherited mix of DNA - instead it’s passed down directly from mothers to their children. If they have girls, then it’ll be passed down to their children too. If they only have boys, though, then that mitochondrial DNA has come to a dead end. Basically it’s matrilineal - it passes down the female line.

    The same with the Y Chromosome. Fathers pass the Y chromosome to their sons. If they only have daughters, well it’s come to a dead end. It’s patrilineal - it passes down the male line.

    DNA analysis shows that all of our mitochondrial DNA is shockingly similar - especially compared to many other animals. Rolling back the clock (by accounting for the tiny random mutations that occur over time) shows that everyone converges to a single person around 155,000 years ago. Before modern humans, as a species, had expanded out of Africa and spread across the world.

    Interestingly, especially so if looking for biblical comparisons, the Y-chromosomal Adam can be traced to around 100,000 years earlier than Mitochondrial Eve - so he did appear first.

    So, the next question might be, “if anatomically modern humans existed for at least 100,000 years before the Mitochondrial Eve, what happened to all the other mitochondria variants - why did we end up with only one?”

    That is simply a numbers game. Compared to many other animals, humans only have relatively few children in their lifetime. This keeps small populations from exploding suddenly, but it also increases the likelihood of only having boys (and stopping that line of Mitochondrial DNA).

    You can map it out on a piece of paper:

    Get five different coloured pens and a black pen.

    Across the top of the page, draw dot in each coloured pen, with a black one beside it. The coloured dots are female, the black ones male). These are the parents.

    Now for the kids. Toss a coin twice - heads for a boy (draw a dot in black pen beneath the parents), tails for a girl (draw a dot the same colour as the mum). Do this for all.

    Now pair up the offspring and carry on.

    You’ll find very quickly, one colour will start to dominate the paper. This represents the Mitochondrial DNA.









  • Lemmy was released as an open-source fediverse alternative to Reddit.

    Just over a year after launch, r/ChapoTrapHouse, moved across after being banned from Reddit. This is likely what you’re referring to. It had well over 100,000 active users on Reddit, so represented a sudden sizable influx of users.

    I’d wager the biggest influx of people by far, though, occurred when Spez upset a majority of mods and many users by banning third party apps.

    People looked for an alternative, and Lemmy was it.

    But why are so many people who lean left politically? Because the Venn Diagram for “people who like the idea of a decentralised platform that supports everybody and is free from the machinations of millionaires”, and “people who would like society that supports everybody and is free from the machinations of millionaires” is nearly a circle.


  • You might be underestimating the timescales involved.

    For example, grass - super simple organism, right? Should have appeared early on? No, dinosaurs appeared before grass did. But when the first grasses did evolve, wow, they were successful on a scale that is hard to overstate.

    The beauty of sexual reproduction, from an evolutionary point of view, is that by its very nature, it allows many experiments to take place at once. The success criteria of each experiment is how many babies can the subject make.

    Little wings evolve on seed pods for the same reason they evolved on anything else. For whatever reason, each step along the way made them a tiny bit more successful at having babies than those without.

    Maybe a little spike makes them slightly less likely to be eaten, a bigger spike less likely still. A flatter spike helped them catch the wind and scatter further afield, and broader ones further still.

    There’s no feedback needed for individuals in this system - it’s literally a numbers game based on who/what can make the most babies. They’re the ones who, millions of years down the line, end up winning.




  • I’m not sure - just think…

    Within less than thirty years there has been:

    A sudden massive increase in the number of people who believe the MMR vaccine causes autism.

    A global pandemic that large numbers of people: Swear didn’t happen, or Was artificially created, or Was a hoax to encourage people to have vaccines that contain something sinister.

    Widespread demonisation of an entire religion.

    A sharp increase in people who don’t believe the holocaust happened.

    A baffling increase in people who believe the Earth is flat.

    In short, people are stupid and surprisingly willing to believe nonsense, despite mountains of evidence to the contrary.

    Were the Jedi actually magical? Nah it was just propaganda by a corrupt council. It was all special effects - seriously, a sword against blasters? Wake up, sheeple.


  • Absolutely - if anything, there’s a reluctance to use formal titles in the UK in general.

    I used to teach at university - students and staff alike just use first names when addressing each other. When signing emails, we just use our first name, no letters, job title, anything.

    It’s even something specifically touched on in our orientation guide for foreign students.

    As for newspapers and Prime Ministers specifically, one of the biggest newspapers, The Guardian, has a cartoonist who has always drawn David Cameron with a condom covering his head. There’s absolutely no deference shown to Prime Ministers here.