mindstalk: (science)
GMO opposition study.
"about 75 percent of the population chose health and safety concerns" though this summary doesn't spell out "GMO being safe to eat" vs. "concerns about more pesticide use".
Opposition anti-correlates with knowledge of genetics: the more you know, the less concerned about GMO safety you are. And in the US (but not Europe), the ignorant considered themselves knowledgeable.
Opposition isn't a left-right thing.

mindstalk: (science)
In more than one of his books, Daniel Dennett talks about this concept, using it to categorize various kinds of creatures. This is someone's 2 page PDF diagram describing the ideas, but having just read one of Dennett's latest books, I'll give my own spin here.

* Darwinian creatures: essentially stimulus-response automata determined by their genes; what is generated is genotypes, what is tested is phenotypes reproducing in the environment.

* Skinnerian creatures: use associationism or reinforcement learning (called conditioning in lab experiments); what is generated is (initially) random behavior, what is tested is the consequences. Darwinian constraints hopefully keep the creature from killing itself outright before it has learned; with more altricial animals, parents may 'teach' their children by setting up the right environments for their children to play in.

* Popperian creatures: have models of the world good enough to generate hypotheses or imagined behaviors and evaluate them by their predicted consequences. There's a small cottage industry of experiments trying to show whether corvids or apes have insight in their tool use, vs. just using a past library of Skinnerian fooling around. Complicated by, well, how does one get such models? Almost certainly by a childhood or lifetime of Skinnerian experimentation, with Darwinian biases (like expecting object persistence) helping: think of a baby trying to stick things in holes, until eventually learning not just that round holes won't go in square pegs, but 'why'.

* Gregorian creatures: this is where the standard description, as captured on the PDF, loses me. But to me it seems that the next level is obviously language, or more generally, imitation, both of which seem uniquely human[1]. To try to stay on theme, what is generated and tested is other people's behavior, which we can then learn from.

In looking for summaries, I saw mentions of Dennett in some older book proposing a fifth level, of the scientific method. At first I dismissed that as just being a mash of Skinnerian experimentation and Popperian modeling. But note that each successive level 'learns' orders of magnitude faster than earlier levels. Likewise, counting from 1650 or later, the scientific community has learned the world far more broadly and deeply than all the millennia of human civilization before it. I feel it's too simple to say that's just due to scientific method: tools like lenses, good clocks, and the printing press helped a lot. But still, there's a big change.

Some other analogies come to mind. 'Gregorian' learning is like enhanced Skinner: instead of being limited to trying your own behaviors at random, you can learn from other people's behavior. "Did you hear what happened when Bob ate that mushroom?" Gregorian, or at any rate human, thinkers are all about giving reasons for our behavior and inferring reasons for other behavior; science sort of enhances Popperian models with reasons, going from "I have observed predictable regularity" to "I can explain predictable regularity and make further predictions from deeper principles."


2018-Aug-05, Sunday 15:23
mindstalk: (science)
I went on a reading binge.

People have made ice as early as 1755 (William Cullen) or 1758 (Ben Franklin and friend). Jacob Perkins made a closed-cycle vapor-compression refrigerator in 1834. A commercial ice-maker dawned in 1854 Australia, with a dozen machines operating by 1861. By 1865 New Orleans was using three of Ferdinand Carre's machines to replace the trade in northern ice cut off by the Civil War. In 1882 the Dunedin sailed from NZ to Britain with a hold of frozen meat.

Basically commercial refrigeration was decades ahead of home use: units were too big and expensive and used too dangerous chemicals, so homes used iceboxes, with manufactured ice replacing harvested ice. GE pioneered a home unit in 1911, but Freon really opened the way. So safe! Except for the ozone layer, so we moved from CFC to HCFC. Which turn out to be strong greenhouse gases.

One alternative is (small amounts of) isobutane or propane: "In 2010, about one-third of all household refrigerators and freezers manufactured globally used isobutane or an isobutane/propane blend". Others are ammonia, CO2, and HFO-1234yf, which has less greenhouse power than CO2 and is hard to ignite, but releases HF if it does burn, not something you want from a flaming car wreck.

I wondered about a CO2 unit bursting and smothering nearby people, but this says the quantity is too small to be dangerous.

All this can make you wonder plaintively if we can't cool with things that are really safe. And we can! One weird option is the vortex tube, but a classic one is the Stirling engine. Famous for running decently on modest heat gradients, it can also cool by literally cranking it in reverse, and is happy using simple air as a working medium. Drawbacks? As far as I can tell, it'd be more expensive, less power-efficient, and less powerful for its weight, than standard tech. How much so, I don't know, though effective enough that Coleman sold some portable units.

Jet engines run on something called the Brayton cycle, which can also be reversed for cooling.

One Stirling note is that vapor-compression apparently runs out of usable refrigerants below -50 C; you need the right vapor/boiling properties. Stirling coolers can go down to cryonic temperatures.

Another thing to note is that while we run everything on electricity these days, the key part of a fridge is the compressor and pump, so it runs fine (and did) on steam, and in theory could be run by watermill, windmill, or muscle-powered treadmill. Yes, you can write a clockwork dystopia where slave labor is running the ice-makers... I'm not sure how many slaves. A small window A/C unit is 1465 Watts; I see numbers giving 160 Watts for the annualized power of an old 18 cubit foot fridge and 40 for a modern one -- or twice that with an ice maker running. Horsepower says a healthy human is good for 75 watts of indefinite effort and an athlete for 260 watts for some hours. "Horsepower" is almost 750 watts but you would need multiple horses to get that effort continuously.

So a large family might be able to run a fridge with voluntary effort, but not an A/C; animal power could provide a fridge and ice making but full A/C would still be expensive.


2017-Jul-09, Sunday 14:10
mindstalk: (Default)
Is Tesla overvalued? Argues Tesla either can't cause disruption, or can't monopolize it. https://www.vox.com/the-big-idea/2017/6/26/15872468/tesla-gm-ford-valuation-justifying-disruption

did Seattle's minimum wage lower employment? two studies, two reports
and two summaries, differing about which sucked

Internet addiction and ethical web design https://aeon.co/amp/essays/if-the-internet-is-addictive-why-don-t-we-regulate-it

Asian anthem authoritarianism http://www.cnn.com/2017/06/28/asia/philippines-anthem-bill/index.html

Air pollution still kills thousands. http://www.npr.org/sections/health-shots/2017/06/28/534594373/u-s-air-pollution-still-kills-thousands-every-year-study-concludes

Intravenous vitamin C as cure for sepsis? http://www.smithsonianmag.com/science-nature/could-deadly-infections-be-cured-vitamin-c-180963843/

origin of Ashkenazi? https://theconversation.com/uncovering-ancient-ashkenaz-the-birthplace-of-yiddish-speakers-58355?utm_source=facebook&utm_medium=facebookbutton

slow progress in parking reform: http://nyc.streetsblog.org/2017/06/27/american-cities-are-chipping-away-at-the-burden-of-parking-mandates/

Sea Trek https://forum.rpg.net/showthread.php?805937-Star-Trek-Alternate-Trek-settings&p=21196309#post21196309

plate tectonics and evolution https://theconversation.com/plate-tectonics-may-have-driven-the-evolution-of-life-on-earth-44571

right to carry increases violent crime, maybe? It uses a fairly new statistical technique to make synthetic controls. The result sounds robust. But the abstract says "elevates violent crime rates, but seems to have no impact on property crime and murder rates". Isn't murder a violent crime?

expert view on reducing gun deaths https://www.nytimes.com/interactive/2017/01/10/upshot/How-to-Prevent-Gun-Deaths-The-Views-of-Experts-and-the-Public.html?_r=0

oil eating bacteria https://www.sciencedaily.com/releases/2017/06/170626155740.htm
Neanderthal dentistry https://www.sciencedaily.com/releases/2017/06/170628131510.htm
host specific enemies and tropical biodiversity https://www.sciencedaily.com/releases/2017/06/170629142949.htm

Vancouver sea wolves http://news.nationalgeographic.com/2016/08/sea-oceans-wolves-animals-science/
mindstalk: (Default)
"Jumping spiders can see the moon." Awesome eyes, apparently. https://www.theatlantic.com/science/archive/2017/06/jumping-spiders-can-see-the-moon/529329/

Cabbage white sex life https://www.theatlantic.com/science/archive/2017/06/butterfly-cabbage-white-vagina-dentata/530889/

Papa John's peppers https://www.thrillist.com/eat/nation/papa-johns-pizza-peppers-pepperoncini-pepper

What happened to the Greenland Vikings (2015). Leans toward the settlements existing for the walrus ivory hunt, and being abandoned after the rise of elephant ivory, the Black Death, and oh yeah, a century of cooling climate. http://www.smithsonianmag.com/history/why-greenland-vikings-vanished-180962119/

Hearing voices and how culture can affect dealing with non-standard neurology. (Psychic, weird, or schizophrenic?) https://www.theatlantic.com/health/archive/2017/06/psychics-hearing-voices/531582/

10 year old article on "positive psychology" http://harvardmagazine.com/2007/01/the-science-of-happiness.html

11 year old article on behavioral economics http://harvardmagazine.com/2006/03/the-marketplace-of-perce.html

Decline of front bench seats in cars https://jalopnik.com/why-front-bench-seats-went-away-1776706852

1660s air pollution https://en.wikipedia.org/wiki/Fumifugium

Jared Diamond on hunter-gatherer childrearing. http://www.newsweek.com/best-practices-raising-kids-look-hunter-gatherers-63611

Suffragette martial arts http://www.atlasobscura.com/articles/suffrajitsu

Nice table of Gospel events https://en.wikipedia.org/wiki/Gospel_harmony#A_parallel_harmony_presentation

Mussels that live on asphalt volcanoes https://www.theatlantic.com/science/archive/2017/06/the-mussels-that-eat-oil/530775/

How New Zealand got PR elections http://www.sightline.org/2017/06/19/this-is-how-new-zealand-fixed-its-voting-system/
mindstalk: (Default)
Powerful new intervention study causally linking lead and crime http://www.motherjones.com/kevin-drum/2017/06/powerful-study-lead-crime-hypothesis/

Story told by cat DNA https://www.theatlantic.com/science/archive/2017/06/cat-domination/530685/

murky story told by dog DNA https://www.theatlantic.com/science/archive/2016/06/the-origin-of-dogs/484976/

Social power causes brain damage https://www.theatlantic.com/magazine/archive/2017/07/power-causes-brain-damage/528711/

America's rising class society https://www.theatlantic.com/business/archive/2017/06/the-hoarding-of-the-american-dream/530481/?utm_source=atlfb

Tattooine's future moisture farms https://www.sciencemag.org/news/2017/04/new-solar-powered-device-can-pull-water-straight-desert-air

India cuts back on new coal, solar is eating its lunch: https://www.nytimes.com/2017/06/02/world/asia/india-coal-green-energy-climate.html?_r=0

Comparative advertising in the Middle East: http://www.boredpanda.com/saudi-arabia-middle-east-censorship/

The Dutch approach to global warming https://www.nytimes.com/interactive/2017/06/15/world/europe/climate-change-rotterdam.html?_r=0

Growing YIMBY movements in SF http://www.beyondchron.org/rising-rents-green-activism-spur-pro-housing-movement/ and Toronto http://torontoist.com/2017/06/yimby-movement-taking-off/

Southern Baptists embrace a gender-neutral bible https://www.theatlantic.com/politics/archive/2017/06/southern-baptists-embrace-gender-inclusive-language-in-the-bible/529935/
mindstalk: (Default)
Discussion of urban taxes, which introduces me to the idea of frontage taxes. My new love, along with land tax. http://urbankchoze.blogspot.com/2016/07/city-taxes-as-urban-growth-policies.html?m=1

GE drops annual employee ratings

Massachusetts bans employers asking for salary history

Evolution of urban animals is rapid

evolution of Europeans and white skin

Some friends got really excited by this: library furniture maker http://www.wcheller.com/index.html

convention bumps may be due to changing willingness to talk to pollsters, rather than actual changing opinion. Though I wonder if this year is an exception. http://www.vox.com/2016/8/1/12341802/polling-clinton-trump-winning

Advocacy of backing into perpendicular parking spaces http://www.vox.com/2016/8/1/11926596/safer-back-into-parking-spaces

Feynman wrong about Faraday cages?

(PDF) 21 page article on Greek voting, acclamation vs. counting: https://melissaschwartzberg.files.wordpress.com/2011/07/schwartzberg_shoutsmurmurs.pdf
mindstalk: (science)
Today I learned of a Stross story, Bit Rot, set between his robot novels Saturn's Children and Neptune's Brood. I read it, it's cool, if dark.

It also led me to learn about soft gamma repeaters and magnetars, which can have magnetic fields so strong atoms are deformed into a 200:1 aspect ratio. I may have heard of this before, but still, wow.

Further link following brought me to pair-instability supernovas. Stars of mass 130-250 Sols can have gamma rays so energetic they form electron-positron pairs, removing the pressure imparted by the gamma ray and causing a collapse leading to total fusion of the star's contents, and total disassembly. No black hole remains, the star literally blew itself up, like a Type Ia supernova.

In turn I learned you can get nucleosynthesis by gamma ray. Also that there are proton-rich nuclei whose origin is not well-explained. We know the reactions that can produce them, we just don't know where those reactions would take place.

Also, there's a unit called the foe, a unit for 1e44 Joules, or 1e51 ergs. 'The word is an acronym derived from the phrase [ten to the power of] fifty-one ergs.[2] It was coined by Gerald Brown of Stony Brook University in his work with Hans Bethe, because "it came up often enough in our work".' as it does if you study supernovas.

And that reminds me of the later Heechee novels, which had energy-based aliens from the early universe known only as the Foe, as they genocided any species that might interfere with their project of returning the universe into a dense hot plasma, which one might say would involve many foes...
mindstalk: (Void Engineer)
I wouldn't have recalled that interplanetary radar has been a thing, but it has, and http://arxiv.org/abs/1301.0825 proposes an interstellar radar system for distant imaging. Claims no new technology is needed, just expense. Lots of expense, he estimates $20 trillion. My friend G and I had estimated a cost for Project Longshot -- an interstellar orbiter (unmanned, no return) -- of $400 billion to $4 trillion. OTOH Longshot would take over a century to reach the nearest star system and would need robust automation to match, though the uncertainties there are part of the cost (and the marginal cost of multiple probes could be lower... as low as $40 billion?) Radar could return data within my lifetime, and once built could image many nearby systems.

G likes to account for things in "war units", $400 billion or a trillion, a la the cost of the Iraq war and associated shenanigans. "We could have another war, or we could send a probe to Alpha Centauri." The radar looks expensive even in that light: $1000 per rich country person for 20 years, or $140 per global person. OTOH per capita income is $10,000 globally, so 1.4% of global GDP for 20 years. As science budgets go, very expensive; less than the global defense budget though.

I'm partly intrigued by the idea, partly amazed that there's finally a case where sending probes seems cheaper than remote observation.

This definitely calls for the Void Engineer icon and the sceince! tag.


2013-Jan-21, Monday 12:59
mindstalk: (kirin)
Annals of a banana republic:
Texas under Perry:cut school budgets, give corporate welfare, get campaign donations
bright note: Daimler says it avoids incentives out of school budgets
"our workers send their kids there"

Cambodia propaganda state via karaoke and comedians. Sounds like something out of Transhuman Space Broken Dreams

MLK day poem

what's good for American Airline isn't good for their execs

government can't save

Several from the Economist:

Indian genes in Australia; stone tool upgrade

soot pollution worse than thought

American embassy reported on Beijing pollution

Austrialia had 40 degree national average temperature , high of 50

global warming governance: geonengineering, migration

safe asset shortage

China nuclear power

four winged protobird
mindstalk: (Earth)
Earth-sized planet found around Alpha Centauri B. With a three-day orbital period, so kind of hot.

"Gay like me"; evangelical pretends to be gay for a year, discovers the closet sucks

Tycoon opts for unilateral geo-engineering
Side note: AIUI, iron fertilization hasn't done much in past experiments. I marvel that no one's suggested it simply to boost fisheries: more algae -> more plankton -> more fish. The open oceans are nutrient deserts, AIUI.

Online "bullying" by liberals

People objected to Uzbekistan forcing children to pick cotton. The government listened; now they're forcing asthmatic doctors and nurses to pick it instead.
Mysterious kidney disease is killing sugar cane workers. Leading hypothesies are "handling nasty chemicals" and "they're working themselves to death in the heat". http://www.guardian.co.uk/world/2012/oct/14/kidney-disease-killing-sugar-cane-workers-central-america
Sugar, high fructose corn syrup, sugar, high fructose corn syrup...

I'm sad this never passed: http://en.wikipedia.org/wiki/Public_Domain_Enhancement_Act

Ben Franklin, futurist: http://lists.extropy.org/pipermail/extropy-chat/2012-October/074565.html

1998 article on high levels of violence in the South: http://www.nytimes.com/1998/07/26/weekinreview/ideas-trends-southern-curse-why-america-s-murder-rate-is-so-high.html?pagewanted=all&src=pm

The second Cuban missile crisis: http://www.bbc.co.uk/news/magazine-19930260

Atheist science-snark vs. religion: http://i.imgur.com/r3RDQ.png

JPL planetary surfaces infographic: http://www.jpl.nasa.gov/infographics/infographic.view.php?id=10795
Rovers; http://www.jpl.nasa.gov/infographics/infographic.view.php?id=10889
Stellar evolution: http://www.jpl.nasa.gov/infographics/infographic.view.php?id=10737
There's lots more.

The changing economics of professional chess: http://www.slate.com/blogs/moneybox/2012/10/09/wages_and_technological_change_in_chess.html

The fall of California's colleges, or the Mississippification of CA: http://www.atimes.com/atimes/Global_Economy/NJ06Dj01.html
mindstalk: (science)

"In 1993, however, its nocturnal assaults were captured on video,[5] proving that at least some Kea will attack and feed on healthy sheep. The video confirmed what many scientists had long suspected, that the Kea uses its powerful curved beak and claws to rip through the layer of wool and eat the fat from the back of the animal. Though the bird does not directly kill the sheep, death can result from blood poisoning or accidents suffered by animals trying to escape."

The world's largest parrot, the Hyacinth macaw, is a meter long. Granted, a lot of that is a long tail. It's still strong enough to open coconuts. Your fingers aren't safe around any large parrot beak but this one seems particularly unwise to taunt.

I forget if I mentioned cannibal chickens here. When last in Spokane, my brother-in-law threw KFC scraps to his backyard chickens, and they went *nuts* over it. Nuts as in racing to pick at the bones. This ties in with things I've heard elsewhere but can't recall, to a hypothesis that there aren't any natural herbivores by inclination, just would-be carnivores with varying abilities to obtain meat and alternate backup strategies.

Ever since my mother told me about feral parrots in Hyde Park in Chicago, I've wondered how they survive the winter. I still don't *know*. My leading hypothesis was sheltering against warm buildings. But the star of North America, the monk parakeet, is kind of temperate zoned, being found as far south as Buenos Aires (up to 35 S, I guess. But Chicago is 42, and I've seen claims of colonies in Wisconsin.) It also uniquely (for parrots) builds big stick nests, which may help it shelter, and it's social in big flocks, so can huddle for warmth.


But the rose-ringed parakeet is outright tropical, with a Wikipedia map showing the Sahel and India as its natural range, and it's colonized Germany, London, and Manchester. What's up with that? I'm still looking at "warm building spots", but have added "they're warm-blooded and covered in feathers, they can survive as long as they get food regularly." Which is also where the urban nature fits in.


It's comforting to know that if I ever want a parrot, there are multiple species with abundance levels of "pest" as opposed to "vulnerable", or extinct like the Carolina parakeet.

'parakeet' seems to mean "small parrot with a long tail", it's not a clade of specifically related spacies.

I have lots of other links, but I guess I'll make this only about parrots.

Except for http://en.wikipedia.org/wiki/Paraphyletic I've often heard "reptiles aren't a real group, because they exclude birds (and mammals)", but there's a word for that, and the idea is of a related group minus members that have diverged sufficiently distinctly. Other examples are prokaryotes (eukaryotes are descended, but treated differently), primates or apes minus humans, ungulates minus whales (!), bony fish minus tetrapods, invertebrates minus vertebrates... pretty common.

Radioactive wine

2012-Sep-19, Wednesday 22:08
mindstalk: (escher)
I've read more of the human evolution book, but am too lazy to blog it. And while plundering the library today, I found Become and Instant Physicist, by Berkeley physicist Richard Muller, author of Physics for Future Presidents. Become is a tiny book, with left hand pages having a little science fact and the right hand pages having an illustration. It's not really "teach you physics", more "have some interesting facts". A good toilet book (as in something you can pick and put down readily, like Calvin and Hobbes collections.)

Sometimes there's a theme, one page leading to another, e.g. the first page is about radioactive C-14 in the atmosphere and organisms, and the second is about radioactive wine. Supposedly the US government has banned the synthesis of consumable alcohol from oil. I'd never thought of this before, but I'd bet converting ethane to ethanol would be easy to do and easily safe. (You have to separate a non-polar gaseous hydrocarbon from a polar liquid alcohol. That's got to be the easiest chemistry ever.) And ethanol's too simple to have chirality. How to make sure someone isn't passing off synthetic alcohol, then? Biological alcohol would be radioactive, from plants recently incorporating C-14 from the air. Fossil fuels have been buried for millions of years, when C-14 has a half-life of 5700 years. Oil and its products isn't radioactive. (Well, not in carbon, anyway.) So apparently the BATF checks booze for radioactivity, wanting it to be present. You could do the same check on alleged biofuels.

"Plutonium is pretty toxic. If inhaled, the letha does is a few thousands of a gram", much worse than arsenic or other common poisons. But botulinum toxin, the poison in botulism, is a million times more lethal than plutonium.

Electricity from a store AAA battery costs $1000 per kilowatt-hour. P=IV, I=1 amp and 1.5 volts, P=1.5 watts, for about an hour. Price = $1.50. Math checks out, I haven't checked the input numbers.

The helium we put in children's balloons is nuclear waste. It's not primordial helium like that which makes up Jupiter, it's the accumulated alpha particles from Earth's radioactivity. Relatedly, geothermal power is indirect nuclear power. Related (this is me now), the one form of fusion power we could do now would be to blow up fusion bombs underground, and tap the hot rock for heat.

The X-Prize was lame. Getting up to 100 km is easy; the Germans sent a V-2 to 85 km in 1942, and by 1946 the US hit 185 km. The hard part is staying up; orbital velocity requires 30x more energy.

Cubic zirconia is supposedly prettier than diamonds. I knew it was comparable.

The anvil shape of thunderhead clouds (cumulonimbus) comes from the warm air of the cloud rising through cool air (air gets colder with height) until it hits the ozone layer (which is warm from the ozone absorbing sunlight) and spreads out.

Hurricane Katrina wasn't that big, it was just the first Category 3 storm to hit New Orleans in the last 30 years.

Organic produce may have less artificial pesticides, but it likely has more natural ones. Farmers select varieties resistant to pests. Resistance means making pesticides. Supposedly those are more carcinogenic than USDA approved ones, too. (I add: also, plants react a lot to getting eaten. Even the same strain of plant probably produces more pesticides when it's being nibbled on than when it's being kept safe by the farmer.)

Filling a car's gas tank is an energy transfer of 12 megawatts. (A gallon has 120 megajoules -- I'd have said 160 -- and takes 10 seconds to pump.)

If you think about the optics, mirrors are as amazing as holograms. But we're used to the mirrors. Though cheap high-quality mirrors are a modern invention. "through a glass darkly" refers to crappy ancient mirrors.
mindstalk: (Default)
I'm currently reading this book, on recent human evolution. It's not an evolutionary psychology book, as that capsule description made someone thing, though it probably will be talking about evolution and the brain. It's by an anthropologist and a physicist, which is a bit odd, but nothing's obviously wrong about it so far.

Main idea isn't new to me: that human evolution, far from being halted by civilization, has in fact sped up. See John Hawks, who *is* an evolutionary biologist (longer piece, by him). Basic idea is that more people = more mutations and thus chances to adapt, and new environments, many of them created by us, means new things to adapt to. (Environment also includes new foods and diseases, and things like cities.)

The book structure is a bit odd; it spends most of chapter 2 talking about the possibility of incorporating adaptive Neanderthal genes, something for which in 2009 they had no real evidence apart from some intermediate skeletons in a few locations, not like the recent genetic evidence of Neanderthal and Denisovian genes. (Which might about as a verified prediction, then.) Speculation on incorporating genes, speculation on what we could have gotten out of them... not entirely divorced from evidence, but still odd.

But there's also math. Simple math. A neutral gene variant -- one with no adaptive effect -- lives or dies by chance, with a chance of taking over a population of 1/2N, N being the size of the population. But, per Haldane, an *adaptive* gene which grants one s% more children (a highly statistical measure, obviously) has probability 2s of sweeping a population. So a gene granting 1% more fitness has 2% chance of taking over. Not high for one such gene... but out of a 100, we'd expect 2 to take over.

(I suspect small number simplification; a 50% adaptive improvement can't be 100% likely to take over, though we can expect good things of it.)

Per Hawks, imagine that the frequency of 1% beneficial mutations is 1 per 10,000 people. Then a population of 10,000 will have 1 such mutation per generation, and it'll take on average 50 generations for one of those mutations to start taking over rather than withering away by chance.

But in a population of a million people, there'd be 100 mutations, and so we'd expect 2 mutations a generation to start being fixed. In 1000 years, 100 successful adaptations, rather than 1.

And we do in fact see lots of genes in the process of 'sweeping' populations. Mostly in metabolism and digestion, disease resistance, reproduction, DNA repair, and the central nervous system. The first two have obvious examples and aren't politically alarming, examples adult like lactose tolerance (less than 8000 years old in Europeans, 3000 years old in Tutsi) and malaria resistance (also 3000 years old.) They say skin color might be another one; hunter-gatherers can get vitamin D from meat, so even in the north don't have a big need for light skin, and several light-skin mutations are younger than agriculture. White people may not have existed 10,000 years ago. Europeans and Asians have more inactive variants of an African gene that promotes salt retention -- useful for high-sweating tropical dwellers, less so in cooler climates, and also leading to hypertension in a modern diet. East Asians apparently have various genes reducing the risk of alcoholism, and the authors speculate that the high rates of diabetes and alcoholism among 'indigenous' populations owe a lot to a near total lack of genetic adaptation to agricultural diets with lots of starch and alcohol.

But the central nervous system? That's the *brain*. Suggesting differences there is politically charged in the way that fire is hot. Yet if evolution happened in other parts of our biology, and it did, why should the brain be immune?

They agree that the amount of time we're talking about isn't enough to build up complex adaptations from scratch. But they point out that you don't need to; simple adaptations can still have big effects. There's huge variation in dogs (chihuahua, Great Dane; smart and friendly border collie, dumb basset hound and mean pitbull), just from shifting the balance of traits present in wolves, plus adding something that means dogs are far more attentive to humans (with the pinnacle of border collies, who can learn words in about 5 repetitions.) They don't mention the prairie and montane vole species, where a single gene change means monogamous pair bonding or not. And shifting the frequency of existing genes is far easier and faster than fixing a new mutation.

So even with all humans sharing the same basic mental mechanisms of intelligence and personality, the proportion of those mechanisms in various populations could easily have changed in the past 10,000 years. But you'll have to wait until I read the rest to hear what...
mindstalk: (CrashMouse)
New article:
Older one I may have linked to before:

Between them, current science seems to say that until 29 weeks the fetus lacks the physical brain connections that correlate with consciousness, and they don't really start functioning until 33 weeks. Even then, the fetus is in a state of constant sedation, from various chemicals plus low blood oxygen, and "wakes up" at the first time with birth. The idea that in a world of gray areas, birth is a rare natural sharp dividing line seems to have real merit, not just convenience, allowing principled distinction between even late abortion and infanticide even if you want to discount the mother's autonomy and focus on the fetus/baby.

In a way, the 'soul' really does enter with the first breath.

(From my limited observations, that's still not much of a soul. On observing a friend's 2 month old, slightly pre-term baby, I quipped that he was barely an animal, let alone human, yet. Nurse shit cry sleep repeat.)


2012-May-22, Tuesday 19:03
mindstalk: (Default)
Small businesses care about cutting arbitrary licensing regulations, not taxes. A libertarian attitude I could get behind. http://www.slate.com/articles/business/the_hive/2012/05/small_business_growth_depends_on_cutting_red_tape_not_taxes_.html

What President Romney would mean for women. http://www.rollingstone.com/politics/blogs/national-affairs/what-president-romney-would-mean-for-women-20120515?link=mostpopular5

IMF calls out Cameron's austerity measures. http://krugman.blogs.nytimes.com/2012/05/22/britains-blunder/

Super round moon. http://www.planetary.org/blogs/emily-lakdawalla/2012/05211206.html

Grover Norquist compares closing tax leaving to Nazis

on voluntarily shorter copyright terms

veteran suicide rates. double the risk, 4x the risk for 17-24

ancient bacteria

chronotypes and school starting time teenage sleep
sleep as simple sit still, evolution of wakefulness

Heartland Institute in climate change trouble

euro unemployment rate

NAACP endorses gay marriage
mindstalk: (Void Engineer)
There are 149 million square kilometers of land, including all the desert, mountains, jungle and tundra. There are about 7 billion humans. This comes out to 2.12 hectares per person, or in snowflake units, 5.2 acres. An American football field with endzones is 5353 square meters, or 1.33 acres; a pro football/soccer field is 7140 square meters, or 1.76 acres. So, depending on where you live, everyone gets 3-4 football fields of their own.

I strongly suspect that with fire and metal tools, let alone power ones, even a wimp like me could totally deforest all that area. Probably not keep tree shoots and saplings from springing up -- that'd be what goats are for -- but chop down all the multi-year large trees and keep new ones from growing far. Also expect that with guns I could kill all the large animals I didn't want. So basically, humans evenly distributed could make all large animals and many trees go extinct, or undergo severe selective pressure.

As for terraforming in the most literal sense, you can imagine how much dirt you could schlep around your five acres. A deep grave is 2x1 meters x 2 deep, and seems doable in at least a day, if not a few hours. (2x2 x 1 deep would probably be easier.) 28 years to dig out your land at that rate. Non-trivial, but conversely the human race could turn over the Earth's whole surface two meters deep in half a lifetime. That's pretty geological. And that's people with shovels, not backhoes.

Also you get to imagine staying alive by farming 5 acres. Or, probably half of that or less, what with the mountains and deserts and tundra and such.

Earth's atmosphere is 5e18 kg. We breathe roughly 10 liters a minutes, or 15 kg/day. So the human race breathes 3.8e13 kg a year, or about 1/100,000 of the mass of the atmosphere. Okay, that doesn't seem huge.

A human's metabolic energy is about 100 Watts. An American uses 10,000 watts via various means, as do Canadians and Scandinavians. So an American is using the energy of 100 humans -- and the 300 million Americans are using enough energy for 30 billion people, and 4x the metabolic energy -- and respired air -- of the whole human race. Humans as a whole are using 1.7e13 watts, vs. American 3e12 watts, and world metabolic 7e11 watts, so with fossil fuels we're "breathing" 1/3,000th of the atmosphere per year.

There's about 3e15 kg of CO2 in the air, vs. the roughly 1e15 kg of air that we "breathe" industrially.

Average land rainfall is 72 cm/year, leading to about 14,500 m3 of water on your 5 acres. Americans use 1880 a year, about half of which is for power plant cooling. Collecting all the water that falls on your land may be a challenge, depending on terrain and climate. So, not using all the water, but definitely making a dent.
mindstalk: (science)
The Do The Math blog has been going through the numbers on various forms of alternative energy, mostly with an eye to how abundant they are, e.g. solar is abundant, wind is useful, tides are niche (locally useful, globally irrelevant.) I'd been planning on summarizing and linking at some point -- but he went and did it himself, with table and links:


His whole schtick, by the way, is back of the envelope calculations on growth, energy, and sustainability issues, fed by and sometimes checked against looked up facts. It's all pretty near. And depressing/alarming. Posts outside this series have included "if exponential economic growth continued, what would that mean?" and "is there enough lead to power the US for a week from lead-acid batteries"?

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