Wednesday, April 2, 2025
Saturday, March 29, 2025
Global warming, painstakingly illustrated
Japanese Diarists have chronicled the arrival of cherry blossoms each year since A.D. 812
The 20-year average is on the steepest decline since records began 1,200 years ago, with the drop accelerating since we started burning fossil fuels
https://buff.ly/YTPdBEJ
Chart source: https://buff.ly/sbl4s9c
Twain - travel as antidote to prejudice
https://youtu.be/Yr8qPKTo8yA?si=V_Mvj7iPbME9Yz02
1:50 Twain circled the globe, and he wrote: "Travel is fatal to prejudice, bigotry, and narrow-mindedness, and many of our people need it sorely on these accounts."
Friday, March 28, 2025
Salmon-killer from tires
https://youtu.be/RESCG-4SYpw?si=nW8iIjFC6xs4iEuQ
A soil mix containing sand, coconut fiber, biochar effectively filters out a poison from car tires, preventing it from reaching rivers where it kills Coho salmon.
Thursday, March 27, 2025
A Woman Who Can Smell Parkinson's
https://www.npr.org/sections/health-shots/2020/03/23/820274501/her-incredible-sense-of-smell-is-helping-scientists-find-new-ways-to-diagnose-di
"....then one day, about 10 years into the marriage, when Les was 31, he came home, and strangely, Joy says, he smelled different. "His lovely male musk smell had got this overpowering sort of nasty yeast smell," she says...Kunath asked one group of people who had Parkinson's and another group of people who didn't have Parkinson's to take home white T-shirts, wear them overnight and then return them. Then Kunath gave the T-shirts to Joy to smell. "They were all given randomized numbers and put in a box, and then she was asked to take each one out and give it a score," he says...In fact, out of all the samples, Joy made only one mistake. She identified a man in the control group...as having the disease. But many months later...that man actually approached him at an event and said, "Tilo, you're going to have to put me in the Parkinson's pile because I've just been diagnosed."
Wednesday, March 26, 2025
Avoiding a simple but catastrophic error.
The key finding here was an error that resulted because "Conducting pre‑flight activities out of sequence increases the risk of missing critical steps and should be avoided." In the operating room, a similar condition occurs when the order of surgical patients is switched, as staff may have subconsciously prepared mental steps for the originally intended operation.
An ATSB occurrence brief details a flight preparation event involving an ATR-72 turboprop airliner at Kalgoorlie Airport, WA.
--What happened--
On the afternoon of 29 January 2025 a [regional jet] was being prepared for an air transport... weather was clear with a temperature of around 38°C. The aircraft had been parked since its arrival that morning at about 0900 local time and the flight crew had fitted the engine air intake covers in anticipation of an extended stop.
The flight crew returned to the aircraft at about 1500 and started preparing for the upcoming flight. The operator had recently emphasized the risk of high cabin temperatures to the passengers, so the flight crew was focused on cooling down the heat-soaked aircraft. As [it was] not equipped with an auxiliary power unit [for weight saving] the use of the air-conditioning packs required starting the number 2 engine in hotel mode.*
After the pilots boarded the aircraft, the first officer started to prepare the flight deck for engine start. The captain disembarked and walked toward the rear of the aircraft to check the airport windsock which was not visible from the cockpit to ensure the correct orientation.[3] The captain then reboarded and joined the first officer for the engine start.
A ground handler was in attendance to make sure the exclusion area around the engine was cleared. After they gave the 'start-engine' hand signal, the flight crew started the number 2 engine with the air bleed valve selected 'off'.[4] The engine start proceeded normally, but when the engine bleed was set to 'on' the crew noticed an immediate rise of the inter-turbine temperature. Closing the bleed valve resulted in the temperature dropping back to normal, but another attempt to open the bleed valve saw the temperature rise again. At this point, the first officer realised that the intake covers had not been removed (Figure 1) and they immediately shut down the engine.
The flight crew then disembarked and found that the engine air intake covers had not been removed from either engine. Additionally, the foam insert from the right-side intake cover had separated and was lodged in the intake. They informed the company operations department and after consultation with the approved maintenance organisation, it was decided that the aircraft should not be flown until an engineer could inspect and test run the engine.
Engineers of the operator's part 145 maintenance organisation attended the aircraft and conducted an inspection of the number 2 engine, followed by a test run at idle and 90% torque. They did not identify any abnormalities, and the aircraft was subsequently released to service.
Further inspection of the covers found that neither had a 'remove before flight' streamer attached and that the stitching on both the number 2 and number 1 cover was in poor condition (Figure 2) and partly loose, which allowed the foam insert to separate from the cover.
--Safety action--
The operator's internal investigation report recommended fitting warning flags to the intake covers of the incident aircraft and that all intake covers across its fleet be checked to further avoid intake cover internal foam ingestion into engines.
The internal report also recommended that involved pilots are reminded of operator's external inspection procedures and receive training in human factors.
--Safety message--
This incident highlights the importance of preparing the aircraft for flight in accordance with the company and manufacturer's procedures, even when competing priorities exist. Conducting pre‑flight activities out of sequence increases the risk of missing critical steps and should be avoided.
Intake and pitot covers may be hard to see due to their location, lighting and weather conditions. To reduce the risk of them being missed during a pre-flight inspection, they should have a contrasting colour and 'remove before flight' flags. Operators should make sure they are periodically inspected as part of their maintenance system, so they remain fit for purpose.
--About this report--
Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.
[1] The auxiliary power unit (APU) is a small gas turbine engine mounted in the tail cone of some larger aircraft to provide autonomous electrical and mechanical power without the use of the engines.
[2] Hotel mode engages the hydraulic propeller brake and allows the turbine to be run to provide auxiliary power and compressed air to the aircraft without the propeller spinning. Compressed air is used to drive the air-conditioning packs which provide cooling to the cabin and cockpit.
[3] The manufacturer's documentation warns against starting the engine in hotel mode with a significant tailwind, as exhaust gasses being blown back into the engine casing may trigger a (false) fire alarm.
[4] Pressurised air diverted from the engine's compressor stage is delivered through the bleed valves for air conditioning and pressurisation as well as de-icing.
**Hotel mode is a feature on ATR 42/72 turboprops replacing an APU by locking the right-hand #2 engine with a 'propeller brake' while allowing the turbine, and therefore also the generator, to run, providing electrical power and bleed air...Hotel Mode seems to be generally disliked for a number of reasons:
- It's very loud, especially if you're lifting baggage next to it
- It consumes a lot of fuel, since you're running a full engine.
- It could be dangerous if the propeller brake is in poor condition and suddenly loses its grip.
This configuration is rare, if not unique amongst aircraft.
Monday, March 24, 2025
10 myths about US tax system
Interesting podcast dispelling myths about US taxation.
44:27 "Elon Musk and his merry band of budget cutters seem to be focusing on symbolic things like DEI contracts, political subscriptions, federal employment that serve a culture war purpose for MAGA warriors. But in terms of the budget deficit, they're not even a rounding error." *
26:56 Myth one is that tax cuts pay for themselves. Tax cuts can bring some extra revenue. They almost never pay for themselves.
Myth two is that tax cuts will starve the beast by forcing Congress to cut spending, but historically it's the opposite. When we cut taxes, Congress increases spending, and when we raise taxes, Congress cut spending.
Myth three is that the middle class pays higher tax rates than the rich. This is not true. If you take a look at all combined federal taxes, the top 1% pays 33%. The middle class pays 12. The bottom pays roughly zero.
Myth four is that those old 91% tax rates in the 1950s produced all this new revenue. The reality is nobody actually paid the 91% tax rates back then. In fact, virtually nobody paid over 50% in a tax bracket and those tax brackets raised virtually no revenue.
Myth five is that Europe funds its bigger governments by taxing the rich more. In reality, they tax the rich about the same as the United States and the entire overage in tax revenue for Europe is the result of value added taxes, which are essentially national sales taxes that hit the middle class.
Myth six is that tax cuts for the rich are the reason we have large budget deficits. The reality is that since 2000, we've cut taxes by 2% of GDP, of which maybe 0.6% of GDP is on the rich, but we've increased spending by 6% of GDP, much bigger driver.
Myth seven asserts that taxing corporations and millionaires can eliminate the deficit. You could tax 'em at a hundred percent and seize all their wealth. It doesn't come close.
Myth eight is that most of the 2017 tax cuts went to corporations and the wealthy. The reality is while they received bigger tax cuts in terms of pure dollars as a share of the taxes they were paying, it was a roughly proportional income tax cut. Everybody got their tax rate dropped by about one percentage point.
Myth nine is that if we go back to the 1980 tax code, essentially repealing the Reagan bush and Trump tax cuts will have painless deficit reduction. In reality, if we did that, the tax burden on the middle class would go through the roof, not just the rich but the middle class to unacceptably high levels.
Myth 10 is that America's corporate taxes are far below international standards. The reality is we had the highest corporate tax rate in the developed world until 2017, and even right now after the 2017 corporate tax cuts, our statutory and effective corporate tax rate is still in the top one. Third. We also collect slightly more than other countries and business taxes when you include pass through corporations.
* DOGE claims $115 billion in savings — but its own 'wall of receipts' shows just $35 billion.
[This is 0.05% of the total budget of 6.9 trillion.]
Saturday, March 22, 2025
Trader Joe's Freakonomics
35:20 A larger at of choices created more interest, but a smaller range of choices created more action (sales.)
Thursday, March 20, 2025
Wednesday, March 19, 2025
Clarion-Clipperton zone
While Norway investigates the risks and zinc/copper/cobalt assets near Svalbard Island, multiple nations are 4:46 vying for lucrative contracts (none yet granted) in the Clarion-Clipperton zone between Hawaii and Guatemala.
Why are millions of Chinese kids raising themselves?
Such a sad, sad story - young kids raising each other at boarding school while impoverished illiterate parents live too far away to visit regularly, earning meager wages that barely support their family.
Tuesday, March 18, 2025
High audit rates for the wealthy
"tax returns of the affluent are generally more complex—and therefore more likely to contain red flags for the IRS"
Fiber-optic unscrambling
This is exactly what I envisioned 20 years ago to make endoscopes much more efficient to manufacture - have a computer unscramble the giver arrangement rather than having to nearly bundle every single fiber in order.
Tedious video, but you'll get the idea at the end.
Monday, March 17, 2025
Sunday, March 16, 2025
World's largest electric ferry
4:50 surprisingly, 280 tons of batteries are actually lighter than the equivalent diesel engine.
Podcast journalist experiment had chat GPT interviewing people and even calling a help line on his behalf
"Evan found a company that would take recordings of his voice and make a voice clone of him, which is what you just heard. Then he hooked up his voice clone to ChatGPT so that it would—you know, it could, like, talk, and it could converse and have a back-and-forth...Evan sends his bot to talk to therapists...he also gave his clone a feature-length biography of himself that he wrote, so that it could draw on that during these conversations...But to make sure it navigated the phone tree correctly this time—and I didn't lose another $90—I set myself up as the middle man, listening in. This was among the stranger experiences in my life. It felt like I was simultaneously eavesdropping on someone else's therapy, getting my own therapy, and hearing a live prank call...Rebecca tried to steer my clone towards some simple exercises. She even gave it daily affirmations to put on post-its around its house. My AI, of course, agreed to do this enthusiastically. It loves to make real-world promises like that.
Wednesday, March 12, 2025
Abandoned supercars in Dubai.
Dubai is known for its luxury, but what happens when the people who own those luxury cars leave the country?
The video explains the phenomenon of abandoned supercars in Dubai (0:00-1:27).
Expats often take out loans to buy cars in Dubai, but struggle to repay them and end up fleeing the country (2:45-3:31).
The cars are impounded by the municipality, then auctioned off to the public (3:49-4:26).
The Dubai police force has a collection of luxury cars that were likely seized from loan defaulters (4:36-7:00).
There are bargains to be had on abandoned cars in Dubai, but buyers need to be cautious (7:00-9:00).
[from the AI summary]
Why do expats flee? Expats often take out loans to buy luxury cars in Dubai (0:59-3:02), but they can struggle to pay them back due to high turnover rates and job instability (3:06-3:12). This can leave them in "toxic debt" (3:04) and facing jail time if they stay (3:15-3:18). Rather than risk imprisonment, they choose to flee the country (3:18-3:25).
What law prevents selling the cars? There isn't one specific law mentioned in the video. Instead, it's a combination of factors:
Loan Defaults: If the car was purchased with a loan, the bank technically owns the car (4:38-4:42), meaning the owner can't sell it.
Financial Crisis & Oil Prices: The global financial crisis and rising oil prices (2:36-2:45) have impacted Dubai's economy, leading to job losses and making it difficult for people to repay loans.
Monday, March 10, 2025
Tsunami secondary waves
The one important fact in this video, at 10:00 - after the next mega-quake tsunami, there will be secondary waves hitting the inundated area for up to 6 hours. Don't go into the inundation zone for 6 hours.
There's isn't much to do to prepare for a tsunami other than know where to seek higher ground, and, based on this video, to stay there a lot longer than I had previously thought.
I was interested to hear that 12:10 once the safety tower was built, people started to think more about planning for disasters. I think it became a stark visual reminder of the constant risk - and got people thinking. That might save more lives than the 400 people it can hold. I agree it seems small, but maybe that's better than nothing, and may represent the entire population of that remote community.
Sunday, March 9, 2025
The genius behind audience conducting
If you don't have time, start at 5:30. This deep dive into the evolution of Jacob Collier's improvising with an audience shows how far he has taken this skill, and the complexity he has achieved.
Voice-over acting
Voice-over acting is easy - well, it's hard. And finding the right person to voice a character is very hard.
Saturday, March 8, 2025
Friday, March 7, 2025
First growth after a forest fire
Shrubs such as willow, blueberry, Labrador tea, and shrub birch re-sprout if the fire lightly burns the soil. If a fire burns deeply and burns the roots, the shrubs depend more on seeds to reproduce. Plants with non-woody stems, such as fireweed and grasses, will also become more plentiful soon after a fire.
Unities
I encountered the Scrabble word "unities." I did not know this as a term in classic drama, where an entire play takes place in one scene, with one plot, within 24 hours. The examples of such movies, or close to it, are interesting discussion in this Reddit. Such as Panic Room, 12 Angry Men, and Die Hard.
Tom Hanks' 2024 movie "Room" is a similar idea but stretched to infinity rather than over 24 hours.
Sunday, March 2, 2025
Geothermal energy
Saturday, March 1, 2025
Accuracy of weather forecasts
analyzed over 20 years' worth of climate model forecasts of ENSO (El Niño-Southern Oscillation)
and found some interesting results... The purest test for models is how well they do in the future, on data that the model has never ever seen. This type of evaluation on "real-time forecasts" is much rarer, and is exactly what Azhar and his co-authors did...The model forecasts can be split into two types, dynamical and statistical. Dynamical models refer to models which take observational data to simulate earth's future climate by using equations that represent our best understanding of the laws of physics...Statistical models, on the other hand, use the historical relationships...and...observational record[s] and then use these relationships to make predictions for the current situation.
Scientific advances that were ridiculed and ignored at first
It's fascinating how many groundbreaking scientific ideas were initially met with skepticism, ridicule, or outright rejection. Here are a few notable examples:
* The Heliocentric Model (Aristarchus and later Copernicus):
* The idea that the Earth revolves around the Sun was proposed by Aristarchus of Samos in the 3rd century BC, and later championed by Nicolaus Copernicus in the 16th century.
* For centuries, the prevailing belief was the geocentric model, which placed the Earth at the center of the universe. The heliocentric model was considered absurd and even heretical.
* It took considerable time and the work of scientists like Galileo Galilei to gain acceptance.
* Germ Theory of Disease (Ignaz Semmelweis):
* Ignaz Semmelweis, a 19th-century physician, observed that handwashing significantly reduced maternal mortality rates in hospitals.
* His suggestion that doctors were transmitting infections was met with hostility and disbelief. He was ridiculed and his findings were largely ignored.
* Later, Louis Pasteur and Robert Koch provided further evidence for germ theory, which revolutionized medicine.
* Plate Tectonics (Alfred Wegener):
* Alfred Wegener's theory of continental drift, which proposed that continents move over time, was initially dismissed by the scientific community.
* His evidence, such as the matching shapes of continents and similar fossil records, was considered insufficient.
* It wasn't until the mid-20th century, with the development of plate tectonics, that Wegener's ideas were validated.
* Helicobacter pylori and Peptic Ulcers (Barry Marshall and Robin Warren):
* Barry Marshall and Robin Warren proposed that the bacterium Helicobacter pylori caused peptic ulcers.
* This challenged the long-held belief that ulcers were caused by stress and diet.
* Their findings were met with skepticism, and Marshall famously ingested a culture of H. pylori to prove his point. They later received the Nobel Prize.
* Quasicrystals (Dan Shechtman):
* Dan Shechtman's discovery of quasicrystals, which have a non-repeating pattern, defied the established rules of crystallography.
* He faced strong opposition and ridicule from prominent scientists, including Linus Pauling.
* His perseverance led to the acceptance of quasicrystals, and he was awarded the Nobel Prize in Chemistry.
* The theory of Evolution by Natural Selection (Charles Darwin):
* Darwin's theory, outlined in "On the Origin of Species," challenged prevailing religious and scientific beliefs about the creation of life.
* It faced intense criticism from both religious figures and some scientists who couldn't accept the idea of species changing over time.
* Despite the controversy, the overwhelming evidence eventually led to its widespread acceptance.
* The concept of neurons (Santiago Ramón y Cajal):
* Ramón y Cajal's work demonstrating that the nervous system is made up of individual cells, or neurons, was initially met with skepticism.
* At the time, the prevailing "reticular theory" suggested that the nervous system was a continuous network.
* His meticulous work and detailed drawings eventually proved the neuron doctrine correct.
* The existence of meteorites:
* For a long time, the idea that rocks could fall from the sky was considered ridiculous.
* Reports of meteorites were dismissed as folklore or hallucinations.
* It wasn't until the early 19th century that scientists began to accept the reality of meteorites, after careful analysis of recovered specimens.
* The idea of blood circulation (William Harvey):
* William Harvey's demonstration that blood circulates throughout the body, rather than being constantly produced by the liver, was a revolutionary concept.
* It contradicted the long-held beliefs of Galen, the dominant medical authority at the time.
* Harvey faced considerable opposition, but his observations and experiments eventually prevailed.
* The understanding of Mental illness:
* For a very long period of time, mental illness was thought of as demonic possession, or moral failing. With the work of people like Philippe Pinel, and others, the idea of mental illness being a medical condition began to gain traction. However, even when that idea started to take hold, many of the treatments were very barbaric. It has been a long road to get to the current understanding of mental health.
Friday, February 28, 2025
Links between gum disease and Alzheimer's
Did you know there's a link between periodontal infection and Alzheimer's? The link is primarily mediated through systemic inflammation and the actions of specific periodontal pathogens. Chronic periodontitis can lead to systemic inflammation, which has been implicated in the pathogenesis of Alzheimer's disease (AD).
Several studies have highlighted the role of pro-inflammatory cytokines such as IL-1β and TNF-α in this process. These cytokines, upregulated during periodontal infections, can promote a pro-inflammatory environment in the brain, contributing to AD-like pathology and cognitive dysfunctions.[1]
Porphyromonas gingivalis, a key pathogen in periodontitis, has been shown to induce systemic inflammation, amyloid β protein deposition, and tau protein hyperphosphorylation, leading to AD-like lesions. This pathogen can alter gut microbiota and disrupt the gut-brain axis, further exacerbating AD pathology.[2] Additionally, bacterial membrane vesicles from P. gingivalis can cross the blood-brain barrier, initiating physiological changes associated with AD.[3]
Moreover, chronic systemic exposure to P. gingivalis lipopolysaccharide (PgLPS) has been shown to promote neuroinflammation and tau hyperphosphorylation in animal models, leading to cognitive deficits.[4] The presence of periodontal pathogens in the brain, such as P. gingivalis, has been detected in autopsy specimens from individuals with AD, suggesting a direct microbial involvement in AD pathogenesis.[5]
In summary, the link between gum disease and Alzheimer's disease is supported by evidence of systemic inflammation, direct microbial invasion, and the resultant neuroinflammatory and neurodegenerative processes.
1. IL-1β and TNF-α Play an Important Role in Modulating the Risk of Periodontitis and Alzheimer's Disease.
Wang RP, et al. J. Neuroinflammation. 2023;20(1):71. doi:10.1186/s12974-023-02747-4.
2. Porphyromonas Gingivalis Induces Disturbance of Kynurenine Metabolism Through the Gut-Brain Axis: Implications for Alzheimer's Disease.
Zhu H, et al. J. Dental Research. 2025;:220345241303141. doi:10.1177/00220345241303141.
3. Bacterial Membrane Vesicles: The Missing Link Between Bacterial Infection and Alzheimer Disease. Butler CA, et al.
The Journal of Infectious Diseases. 2024;230(Supplement_2):S87-S94. doi:10.1093/infdis/jiae228.
4. GSK3β Is Involved in Promoting Alzheimer's Disease Pathologies Following Chronic Systemic Exposure to Porphyromonas Gingivalis Lipopolysaccharide in Amyloid Precursor Protein Knock-in Mice. Jiang M, et al.
Brain, Behavior, and Immunity. 2021;98:1-12. doi:10.1016/j.bbi.2021.08.213.
5.Porphyromonas Gingivalis and Alzheimer Disease: Recent Findings and Potential Therapies.
Ryder MI. Journal of Periodontology. 2020;91 Suppl 1:S45-S49. doi:10.1002/JPER.20-0104
Wednesday, February 26, 2025
Pileated tongue
Cool high-resolution video if a Pileated woodpecker's tongue
https://youtube.com/shorts/rs_rx6JvsbQ?si=AZWdcDXYE2ksbdDp
NYTimes: 36 Hours in Dubai
36 Hours in Dubai https://www.nytimes.com/interactive/2024/12/05/travel/things-to-do-dubai.html?smid=nytcore-android-share
Lots of interesting things to do in Dubai. Glad NYT went there to investigate.
Tuesday, February 25, 2025
Wing Walker repairs
This footage is amazing to me. It seems almost impossible to climb for one plane to another mid-flight: the wing of the plane she leaves would rise up while the wing she climbed onto would drop, and it would take very skillful reckoning by both pilots to prevent the wings striking each other - let alone the risky repair she went on to do.
Friday, February 21, 2025
Hiccup cure
A simple way to stop hiccups is to take three deep breaths in quick succession without exhaling between them, then hold your breath for 15-30 seconds before slowly exhaling; this essentially "resets" the diaphragm spasms causing hiccups by forcefully stimulating the phrenic nerve that controls it.
Monday, February 17, 2025
Mexico City has preserved an ancient near-perfect farmland
An intensely rich biomass created over millennia from floating islands in a landlocked (endorheic) lake.
Saturday, February 15, 2025
Recycling wind turbine blades
Crushing up old wind turbine blades into material to make concrete stronger and more durable road surfaces.
Friday, February 14, 2025
Why US can't use the oil it produces
I found this so interesting. When people say "We need energy independence," it actually can't happen...because we don't have the kind of refineries to process the type of oil we produce, and there's way too much red tape and expense to change the types of refineries we already have. It would be prohibitively expensive to convert domestic refineries to handle the type of oil we produce.
Thursday, February 13, 2025
Smoking a beehive
Watch the amazing exodus at 7:35 once the queen has been transferred - thousands of worker bees migrate into the new hive.
Why does smoke calm bees?
Though scientists are not 100% certain, the smoke is believed to work in two main ways:
1) By blocking the bees' pheromone sensitivity. This means that the intruder alert/attack message isn't spread around the hive, reducing the risk of stings.
2) By stimulating the bees' instinctual response to wildfires. When bees believe a fire is coming, they fly into the hive and start gorging themselves on honey, in preparation for leaving the hive to search for a new home. So, the bees are contained and distracted while the beekeeper works.
Ahhh - coffee...in unique ways
I really like the idea of the Mexican coffee .
0:57 "Cafe de olla" (pot coffee) with sugar, cinnamon and orange peel.
Also, 2:01 coffee with cheese in Sweden.
And, 3:38 "egg coffee" in Viet Nam, developed when milk was rationed in the 1970's, with the whipped egg yolks providing a "fatty, sweet & savory" accompaniment to the coffee.
Inside Africa's food forest mega-project.
I find this kind of "desert greening" project fascinating - seems like a great humanitarian investment that really involves local people in their future.
2:28 "in the Sahel we find an age-old water harvesting structure called the "half moon." This simple structure has capacity to store this water [as it] soaks down into the ground."
8:12 "this diverse perennial poly-culture here provides types of foods that can be harvested in the dry season...
8:44 the "Great Green Wall" is actually rebuilding the ecological matrix of a region"
11:21 "when you do this type of land treatment, your actually helping areas [further] downstream because [not only is] this water soaking in them you also get this [arid] wind protection, so for every hectare that you restore, you actually affect three times that amount of land."
Eddie Murphy discovers what it's like to be a white man
Eddie Murphy finds that white people get bank loans for free and enjoy parties on the public bus.
Tuesday, February 11, 2025
Why do some bad traits evolve, and good ones don't?
I find this whole question intensely interesting. There are many interesting answers in the thread, but this one is pretty succinct.
During the process of selection, individuals having disadvantageous traits are weeded out. If the selection pressure isn't strong enough then mildly disadvantageous traits will continue to persist in the population.
So the reasons for why a trait is not evolved even though it may be advantageous to the organism, are:
There is no strong pressure against the individuals not having that trait. In other words lack of the trait is not strongly disadvantageous.
The trait might have a tradeoff which essentially makes no change to the overall fitness.
Not enough time has elapsed for an advantageous mutation to get fixed. This doesn't mean that the mutation had not happened yet. It means that the situation that rendered the mutation advantageous had arisen quite recently. Consider the example of a mutation that confers resistance against a disease. The mutation wouldn't be advantageous if there was no disease. When a population encounters the disease for the first time, then the mutation would gain advantage but it will take some time to establish itself in the population.
The rate for that specific mutation is low and therefore it has not yet happened. Mutation rates are not uniform across the genome and certain regions acquire mutations faster than the others. Irrespective of that, if the overall mutation rate is low then it would take a lot of time for a mutation to arise and until then its effects cannot be seen.
The specific trait is too genetically distant: it cannot be the result of a mutation in a single generation. It might, conceivably, develop after successive generations, each mutating farther, but if the intervening mutations are at too much of a disadvantage, they will not survive to reproduce and allow a new generation to mutate further away from the original population.
The disadvantage from not having the trait normally arises only after the reproductive stage of the individual's lifecycle is mostly over. This is a special case of "no strong pressure", because evolution selects genes, not the organism. In other words the beneficial mutation does not alter the reproductive fitness.
[Koinophilia is an evolutionary hypothesis proposing that during sexual selection, animals preferentially seek mates with a minimum of unusual or mutant features, including functionality, appearance and behavior.]
Koinophillia resulted in the trait being unattractive to females. Since most mutations are detrimental females don't want to mate with anyone with an obvious mutation, since there is a high chance it will be harmful to their child. Thus females instinctually find any obvious physical difference unattractive, even if it would have been beneficial. This tends to limit the rate or ability for physical differences to appear in a large & stable mating community.
Evolution is not a directed process and it does not actively try to look for an optimum. The fitness of an individual does not have any meaning in the absence of the selection pressure.
Monday, February 10, 2025
Best use of AI yet - Protein folding by AI in intriguing sequential steps
Using AI to solve protein folding problems at an astoundingly faster rate than previously thought possible, suggests that other bedding human problems like climate change and cancer treatment and congenital disease might be similarly solved.
Friday, February 7, 2025
Dry wick for soft ground under buildings
Would this work? What prevents the tube from collapsing?
The reduction of water content of the saturated layers allows the soils to better accommodate superimposed loads and minimizes future settlement. - Menard company
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