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The Siberian silver fox study makes it very difficult to avoid the conclusion that behavior (e.g. tameness) in canines is a heritable trait that can be selected for.

Beginning in 1952 wild silver foxes have been bred in Siberia selecting solely for friendliness. Notable changes were found after 6 generations. By the 30th generation, 70-80% of the selected population were "domesticated elite", which "are eager to establish human contact, whimpering to attract attention and sniffing and licking experimenters like dogs." Similar experiments were performed in the opposite direction, selecting for aggression. https://en.wikipedia.org/wiki/Domesticated_silver_fox


Heritability of traits is a really messy and difficult problem. Sere, you can breed tameness into wild foxes, but that doesn't mean you can easily breed more tameness into already tame foxes/dogs. There might be some low-hanging fruit that's easy to exploit and after that, it's mostly random chance and the environment that determines things. But that again depends on what the environment is like - if all dog owners routinely raise their puppies in the same extreme way, their inherited differences might either be invisible because none get the chance to express them, or even more significant because that's the only factor left that can sort out how they respond to their environment.


One can start with an already tame population of foxes/dogs and select for aggression. Aggression would be a useful trait in a breed desired for protection/guarding.


People have been doing that and yet somehow those aggressive breeds still frequently produce harmless puppies, so it's not obvious that breeders have actually achieved it. Maybe dogs have been domesticated for so long that we can't undo their behavior with just a couple of hundred years. Or maybe we can. It's hard, not obvious.


Interestingly, cyclobutane and cyclopropane do not have a large difference in ring strain (within about 4% of each other). Cyclopropanes are well known in natural product structures. One of the weirdest is this natural product, U-106305, which has 6 cyclopropanes. Made by a strain of Streptomyces! https://pubs.acs.org/doi/pdf/10.1021/ja9619420


Moonwalking with Einstein de-mystified memory for me. As mrock described, in the beginning it was a lot of work building palaces and making associations, but like a muscle, things quickly got easier. In time, memorizing a list of 30 or so became pretty easy. I was able to memorize a list of 875 North American bird species and then recite it from memory. Took about 35 min to read it all back.


That's awesome. Did it change your relationship with or experience of birds?


It was like taking a walk around the perimeter of a huge mansion before actually exploring it. I learned the names of lots of birds and was able to associate them together, but didn't really learn their characteristics. In time I let the associations fade. Mostly it just gave me the confidence that I was capable of doing something like this if needed. Thanks for all the time you took in answering people's questions on this thread.


I have been working on this site for 11 years, has 400 free articles on intro organic chemistry: https://www.masterorganicchemistry.com Probably the most fun thing I ever did was breaking down the mechanisms of 25-30 reactions into individual steps, and then assigning a musical note to each step. Playing the sequence of notes helps you recognize the patterns behind the reactions. One pattern in particular (protonation-carbonyl addition-deprotonation-protonation-elimination-deprotonation, or PADPED) covers the mechanism of at least 8 superficially different reactions. Another great organic chemistry resource: https://organicchemistrydata.org/hansreich/resources/pka/#pk...


Thank you! I will have a look.


Indeed. My friends thought I was exceptionally smart to be able to recite a list of 875 north american bird species from memory, when in fact I'd just put in a lot of work building memory palaces. The book demystified a lot.


For a different source, Freeman Dyson's biography, Disturbing the Universe, is extraordinarily worthwhile. He has crazy Feynman stories too, and Dyson is a very sober witness to the bongo-drum-playing, picking-up-hitchhikers, getting-pulled- over-for-speeding Feynman that comes across in the books.


Regus is valued at about 10k per desk. Wework is valued at about 160k / desk (August 2017 numbers, see Aug 25 2017 WSJ).

What does Wework do that Regus doesn't, that accounts for 16x the value?


Free beer?


I will make you a long bet of $100 that no country bans the sale of new diesel or petrol cars by the end of 2025.


That could be more of a problem for ICE car manufactures than a solution. Regulations are the only thing that will force these people to innovate out of their current existence. With that gone, its basically EV departments have to navigate through powerful political cartels within the company running the existing product cash cows. In short it won't happen.

There is a reason why Microsoft cannot product a good mobile OS to date. It requires sidelining their biggest cash cow, their desktop OS.


Was just wondering today how to build one, thank you.


>In addition to the other fine points: A fundamental job of a life form is to pump entropy out faster than the environment can pump it in.

Yes. From a chemistry perspective, this requires a membrane, or barrier, that separates "life" from "non-life". It also requires mass transport across that barrier in both directions, which would presume liquid inside that barrier. A third variable is the mass of the planet, which dictates which molecules can be present in the atmosphere, and the temperature, which dictates physical states. The requirement for a barrier and mass transport via liquid already imposes restraints on the chemistry that rule out most of the periodic table. Metals lose their electrons too easily. After metals, you're not left with much to work with. Carbon compounds in water is still the best idea we have. Simple long chain carboxylic acids spontaneously make membrane-like micelle structures in water. If anyone has any better ideas, there's a Nobel Prize for the first person to create life from non-life. Go for it.


But this leaves pressure and specific volume out of the equation, does it not? Lots of molecules can be liquid in the right environment.


Sure, which is why environments like Europa are exciting.


Why would it presume liquid inside the barrier and not simply a fluid (including e.g. gasses)?


A lot of the chemical reactions required to maintain life as we know it involve charged intermediates. These are not generally soluble in the gas phase as they have very low vapor pressures.


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