Later On

A blog written for those whose interests more or less match mine.

Archive for the ‘Evolution’ Category

How much of you is your genes?

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Kevin Drum has a fascinating post on those aspects of us that are genetically determined. From the post:

. . . Overall cognition, which is basically intelligence, is about 70% inherited. The other 30% is influenced by shared and non-shared environment. The same is true for oral reading. The subcomponents of intelligence, fluid and crystallized cognition, are a bit less inheritable.

Hyperactivity is almost entirely inherited. Anxiety, by contrast, is only weakly inherited. It’s apparently caused mostly by environmental factors.

Reading for pleasure is almost entirely influenced by genes. Oddly, though, . . .

Read the whole thing.

Written by Leisureguy

31 May 2023 at 9:44 pm

The Insane Biology of: The Octopus

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Written by Leisureguy

25 May 2023 at 7:27 pm

Sleeping beauties: the evolutionary innovations that wait millions of years to come good

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Andreas Wagner has in the Guardian an edited extract from his book Sleeping Beauties: the Mystery of Dormant Innovations in Nature and Culture:

What are the most successful organisms on the planet? Some people might think of apex predators like lions and great white sharks. For others, insects or bacteria might come to mind. But few would mention a family of plants that we see around us every day: grasses.

Grasses meet at least two criteria for spectacular success. The first is abundance. Grasses cover the North American prairies, the African savannahs and the Eurasian steppes, which span 5,000 miles from the Caucasus to the Pacific Ocean. A second criterion is the number and diversity of species. Since the time grasses originated, they have evolved into more than 10,000 species with an astonishing variety of forms, from centimetre-high tufts of hair grass adapted to the freezing cold of Antarctica to the towering grasses of northern India that can hide entire elephant herds, and to Asian bamboo forests, with “trees” that grow up to 30 metres tall.

But grasses weren’t always so spectacularly successful. For tens of millions of years – most of their evolutionary history in fact – grasses barely eked out a living. Their origin dates back to the age of dinosaurs, more than 65m years ago. But for many millions of years, the fossil record suggests, they were not abundant. In fact, it wasn’t until less than 25m years ago that they became the dominant species that we recognise today.

Why did grasses have to wait 40m years for their proverbial spot in the sun? This mystery deepens once you know that, early on, evolution endowed grasses with multiple survival-enhancing innovations. Among them are chemical defences like lignin and silicon dioxide that grind down the teeth of grazing animals. These features also protect grasses against drought, as do sophisticated metabolic innovations that help them conserve water.

With these and other innovations, you’d think that grasses would have quickly become dominant. But their delayed success holds a profound truth about new life forms. Success depends on much more than some intrinsic characteristic of a new life form, like an enhancement or a novel ability bestowed by an innovation. It depends on the world into which this life form is born.

Grasses are among myriad new life forms whose success – measured in abundance or diversity of species – was delayed for millions of years. The first ants appeared on the scene 140m years ago, but ants did not begin to branch into today’s 11,000 or more species until 40m years later. Mammals with various lifestyles – ground-dwelling, tree-climbing, flying or swimming – originated more than 100m years before they became successful 65m years ago. And one family of saltwater clams had to wait for an astonishing 350m years before it hit the big time, diversifying into 500 species.

These and many other new life forms remained dormant before succeeding explosively. They are the sleeping beauties of biological evolution. They cast doubt on many widely assumed beliefs about success and failure. And these doubts apply not just to the innovations of nature, but also to those of human culture.

For life to develop, it had to overcome challenges through innovation – such as how to extract energy from minerals, from organic molecules and from sunlight, or how to escape predators and stalk prey. Each of these kinds of challenges can be met in many ways, each emerging as a creative product of biological evolution, each embodied in a species with a unique lifestyle, millions of them and counting, as evolution marches on.

Innovation did not stop with biological evolution. Species with sophisticated nervous systems including chimpanzees, dolphins and crows have discovered simple technologies – tools they use to hunt or gather food. In the 12,000 years since the agricultural revolution, human culture has come up with revolutionary innovations such as mathematics and writing, as well as countless smaller ones, from the wheel to wallpaper. Countless sleeping beauties are among them. They include breakthrough technologies like radar, initially ignored, and scientific discoveries like the genetic laws of inheritance, which were neglected for decades.

Granted, nature and culture do not create in exactly the same way. The ink and paper of Newton’s Principia is a different substrate of creativity than the cells, tissues and organs in a blue whale. A writer’s grit in wrestling with the 15th draft of a chapter is a different motor of creation than random mutations of DNA. A patent’s commercial value is a different measure of success than how often the bacterium Escherichia coli divides every day.

But beyond these differences lie deep similarities. One of them is that a great number of innovations arrive before their time. Creative products without apparent merit, value or utility, but with the power to transform life given enough time, are everywhere in nature and culture. The sleeping beauties of nature can help us understand why creating may be easy, but creating successfully is beyond hard. It is outside the creator’s control.


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T
he caterpillars of monarch butterflies are addicted to . . .

Continue reading.

Written by Leisureguy

25 April 2023 at 12:23 pm

Interesting thread on the Covid-cancer connection

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I came across a thread that begins with this post:

Epstein-Barr virus, human papillomavirus, hepatitis B and herpes virus-8 are all viruses that can increase the risk of cancer. There is preliminary evidence #COVID19 could also. We won’t know for many years, by which time, many will have been convinced to repeatedly be infected because they were told it was safe & they didn’t like masks. An ounce of prevention today could be worth a ton of cure later. Why be a lab rat and only find out later you should’ve been more cautious today? #WearAMask

Along the way, someone commented:

my 3 cats got covid when I did in 2020. Now 2 are dead from cancers, and the 3rd has kidney disease

One was only 30, in human years

And see also this article in Nature: “COVID drug drives viral mutations — and now some want to halt its use.” The Eldest tells me that that particular drug is already highly restricted exactly for the reasons described in the article. Moreover, as she points out, “Now that COVID is in animals (deer, cockroaches, etc) and so many people are having second and third rounds of infections because they have discontinued masking, there will be many, many new mutations in any case, sadly. Each new infection is a chance for a successful mutation.”

Be careful out there. Wear an N95 mask in indoor public places.

Written by Leisureguy

8 February 2023 at 10:46 am

How the Western Diet Has Derailed Our Evolution

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Moises Velasquez-Manoff wrote in Nautilus in 2015:

For the microbiologist Justin Sonnenburg, that career-defining moment—the discovery that changed the trajectory of his research, inspiring him to study how diet and native microbes shape our risk for disease—came from a village in the African hinterlands.

A group of Italian microbiologists had compared the intestinal microbes of young villagers in Burkina Faso with those of children in Florence, Italy. The villagers, who subsisted on a diet of mostly millet and sorghum, harbored far more microbial diversity than the Florentines, who ate a variant of the refined, Western diet. Where the Florentine microbial community was adapted to protein, fats, and simple sugars, the Burkina Faso microbiome was oriented toward degrading the complex plant carbohydrates we call fiber.

Scientists suspect our intestinal community of microbes, the human microbiota, calibrates our immune and metabolic function, and that its corruption or depletion can increase the risk of chronic diseases, ranging from asthma to obesity. One might think that if we coevolved with our microbes, they’d be more or less the same in healthy humans everywhere. But that’s not what the scientists observed.

“It was the most different human microbiota composition we’d ever seen,” Sonnenburg told me. To his mind it carried a profound message: The Western microbiome, the community of microbes scientists thought of as “normal” and “healthy,” the one they used as a baseline against which to compare “diseased” microbiomes, might be considerably different than the community that prevailed during most of human evolution.

And so Sonnenburg wondered: If the Burkina Faso microbiome represented a kind of ancestral state for humans—the Neolithic in particular, or subsistence farming—and if the transition between that state and modern Florence represented a voyage from an agriculturalist’s existence to 21st-century urban living, then where along the way had the Florentines lost all those microbes?

Earlier this year I visited Sonnenburg at Stanford University, where he has a lab. By then he thought he had part of the answer. He showed me, on his computer, the results of a multigenerational experiment dreamed up by his wife, Erica, also a microbiologist.

When the Burkina Faso study was published, in 2010, the question of what specific microbes improved human health remained maddeningly elusive, but evidence was beginning to suggest that diversity itself was important. So despite their relative material poverty, these villagers seemed wealthy in a way that science was just beginning to appreciate.

Where did that diversity come from? Humans can’t digest soluble fiber, so we enlist microbes to dismantle it for us, sopping up their metabolites. The Burkina Faso microbiota produced about twice as much of these fermentation by-products, called short-chain fatty acids, as the Florentine. That gave a strong indication that fiber, the raw material solely fermented by microbes, was somehow boosting microbial diversity in the Africans. . .

Continue reading.

And BTW, the two vegetable ferments I have going, the Christmas ferment and the Beets & Leeks ferment, are doing fine.

Written by Leisureguy

18 December 2022 at 7:25 pm

Bipedalism and Tales of Other Evolutionary Oddities

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Six stages of evolution of humans, each stage represented by a figure, showing the increasingly upright posture, with each figure a skeleton.

Telmo Piavani writes the The MIT Press Reader:

You will be hard-pressed to find an animal that has no rudimentary or useless traits: Atrophied eyes, discarded wings, or male breasts, to name just a few of many.

These are all signs of history, legacies of distant relatives, disused structures that evolution will tolerate for a while or will reuse at a later date should they be needed, as in the case of the eyes that can be found below the skin of some moles, or penguin wings used as fins, or insect wings that are repurposed as halteres. From the nucleus of each cell to the architecture of our organs, the human body, too, bears the traces and wounds of a long and contrasting evolutionary history. Naturally, not everything in our bodies serves a purpose, otherwise we would have to ask ourselves why we (and not the Neanderthals) have chins. To look for a function at all costs would be ridiculous. Indeed, despite the beautiful proportions of da Vinci’s Vitruvian Man inscribed within a circle and square, our physique is mainly a compendium of mismatches worthy of Homer Simpson.

In males, for example, what is the point of the urethra passing right through the center of the prostate, whose function is in no way linked to urination? The result is that, when the latter becomes inflamed and enlarged over the years, there is a lot of unnecessary pain. This makes absolutely no sense other than the fact that until recently people did not grow old enough to suffer from such an ailment. It makes no sense, but this is evolution. Imperfection in nature arises from the need to find compromises between different needs and antagonistic selective drives. This means that an advantageous trait can evolve and succeed despite the fact that its owners pay the price in the form of annoying side effects.

The appendix is another good case in point. While recent studies suggest it may have some secondary advantages related to the immune system or could act as a reservoir of good bacteria in case of infections, there were numerous potential anatomical solutions that would have been more efficient and less painful than this one. Today, when needed, we can get by through an emergency operation, but to have a wormlike appendix in our bellies is decidedly a bad idea.

Another such example is the external scrotum. Many mammals have one, including us, and we know that it plays an important role in cooling the testicles for the production of spermatozoa. Nonetheless, many mammals — including elephants, hyraxes, anteaters, dugongs, elephant shrews, and golden moles — have testicles inside their bodies, where they’re far less vulnerable. Thus the external scrotum is useful but not essential.

Concealed ovulation is yet another oddity that we have almost uniquely. Human males do not perceive the moment when females are ready to conceive. In the more reasonable baboons, mandrills, chimpanzees, and bonobos, the female in estrus is recognizable due to the appearance, turgidity, and coloration of her genitals and the emanation of specific odors. This means that even the most obtuse male will sooner or later understand when it is time to do his duty, while in the human species, this does not happen. For us, and a few other species such as the gray langur of Southeast Asia, ovulation is concealed. This all goes to produce a great sense of insecurity in the males, who do not know if their copulation, which is often obtained at a high price, has been successful or not.

The list of evolutionary oddities goes on and on. If you can move your auricula like elephants, it means you have useless but still-functioning muscles in your ears. The caudal vertebrae that are fused together under the pelvis are in fact the remnants of your tail, and the coccyx still serves as a point of attachment for some muscles. Just ask the opinion of anyone who has fallen down the stairs and violently hit the edge of a step. Those who suffer from debilitating back pain well understand the imperfections of human bipedalism, a compendium of locomotor inefficiency that made us human. For a moment, let us consider our strange posture, perhaps the most imperfect of our adaptations.

The Most Imperfect of Revolutions: Walking

The human spine did not evolve out of thin air. The supple spine of a quadruped or brachiator (the preexisting constraint and evolutionary inertia) was straightened out, meaning that the weight of the whole body now rests on a single axis and off-loads on the two legs. As a result, the spine is curved and the vertebrae are subjected to undue pressure. Nerves and muscles have readjusted themselves as far as possible, but not enough to prevent sciatica, hernias, and flat feet. If, after all that effort made to stand upright on its lower limbs, that biped spends all of its days sitting at a desk or in a car, however, we are actively in search of the pain of imperfection.

So why become bipedal? This question is actually  . . .

Continue reading.

Written by Leisureguy

1 December 2022 at 11:49 am

Posted in Evolution, Science

Another Path to Intelligence

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Close-up profile photo of large Pacific octopus.

James Bridle writes in Nautilus:

It turns out there are many ways of “doing” intelligence, and this is evident even in the apes and monkeys who perch close to us on the evolutionary tree. This awareness takes on a whole new character when we think about those non-human intelligences which are very different to us. Because there are other highly evolved, intelligent, and boisterous creatures on this planet that are so distant and so different from us that researchers consider them to be the closest things to aliens we have ever encountered: cephalopods.

Cephalopods—the family of creatures which contains octopuses, squids, and cuttlefish—are one of nature’s most intriguing creations. They are all soft-­bodied, containing no skeleton, only a hardened beak. They are aquatic, although they can survive for some time in the air; some are even capable of short flight, propelled by the same jets of water that move them through the ocean. They do strange things with their limbs. And they are highly intelligent, easily the most intel­ligent of the invertebrates, by any measure.

Octopuses in particular seem to enjoy demonstrating their intelli­gence when we try to capture, detain, or study them. In zoos and aquariums they are notorious for their indefatigable and often suc­cessful attempts at escape. A New Zealand octopus named Inky made headlines around the world when he escaped from the National Aquarium in Napier by climbing through his tank’s overflow valve, scampering eight feet across the floor, and sliding down a narrow, 106-­foot drainpipe into the ocean. At another aquarium near Dun­edin, an octopus called Sid made so many escape attempts, including hiding in buckets, opening doors, and climbing stairs, that he was eventually released into the ocean. They’ve also been accused of flood­ing aquariums and stealing fish from other tanks: Such tales go back to some of the first octopuses kept in captivity in Britain in the 19th century and are still being repeated today.

Otto, an octopus living in the Sea­Star Aquarium in Coburg, Germany, first attracted media attention when he was caught juggling hermit crabs. Another time he smashed rocks against the side of his tank, and from time to time would completely rearrange the contents of his tank “to make it suit his own taste better,” according to the aquar­ium’s director. One time, the electricity in the aquarium kept shorting out, which threatened the lives of other animals as filtration pumps ground to a halt. On the third night of the blackouts, the staff started taking night shifts sleeping on the floor to discover the source of the trouble—and found that Otto was swinging himself to the top of his tank, and squirting water at a low­-hanging bulb that seemed to be annoying him. He’d figured out how to turn the lights off.

Octopuses are no less difficult in the lab. They don’t seem to like  . . .

Continue reading

Written by Leisureguy

20 November 2022 at 8:44 am

‘Island Syndrome’ – how species change when they move to isolated islands

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McKinley Valentine’s The Whippet often has good articles, and The Whippet #158 has several, including this one on island syndrome:

The Cabot’s Tragopan colours [the subject of the preceding article – LG] reminded me of this – on remote islands, male birds lose their fancy colours and plumage, because it’s a small dating pool and the female birds don’t have any better options. Since there are fewer different species overall, birds also don’t have to bother distinguishing themselves from other species.

Isolated ecosystems – which includes not just islands, but caves, valleys, desert oases and ‘sky islands‘ (isolated mountain-tops) – have fewer predators, less biodiversity and less interspecies competition, so they tend to change in predictable ways:

  • Big animals get smaller (“insular dwarfism”) and small animals get bigger (“insular gigantism”). See: pygmy elephants and coconut crabs.
    With a smaller variety of species, there’s less need for animals to occupy a specific niche, so they all shift towards the middle.
  • Birds and insects lose their wings (see: the kiwi and kakapo) because they don’t need them to escape predators
  • Colours get duller; the male and female of a given species look more alike.
  • Mothers have smaller litters of fitter animals – it’s more about getting one awesome kid to adulthood than having thousands and playing the numbers game.
  • Their brains shrink.
  • They get docile and less territorial (see: the dodo)

Fancy colours, clever brains, big pectoral muscles for flapping wings, hypervigilance – they all take a lot of energy, and animals that waste energy on unnecessary things get out-evolved.

Plants do the same thing – the big ones . . .

Continue reading.

Written by Leisureguy

26 October 2022 at 11:12 am

Seeing and somethingness

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Nicholas Humphrey, emeritus professor of psychology at the London School of Economics and author of many books on the evolution of human intelligence and consciousness, the latest being Sentience: The Invention of Consciousness, writes in Aeon:

The cover of New Scientist magazine 50 years ago showed a picture of a rhesus monkey, with the headline ‘A Blind Monkey That Sees Everything’. The monkey, named Helen, was part of a study into the neuropsychology of vision, led by Lawrence (Larry) Weiskrantz in the psychology laboratory at the University of Cambridge. In 1965, he had surgically removed the primary visual cortex at the back of Helen’s brain. Following the operation, Helen appeared to be quite blind. When, as a PhD student, I met her a year later, it seemed nothing had changed.

But something puzzled me. In mammals, there are two main pathways from the eye to the brain: an evolutionarily ancient one – the descendant of the visual system used by fish, frogs and reptiles – that goes to the optic tectum in the mid-brain, and a newer one that goes up to the cortex. In Helen, the older visual system was still intact. If a frog can see using the optic tectum, why not Helen?

While Weiskrantz was away at a conference, I took the chance to investigate further. I sat with Helen and played with her, offering her treats for any attempt to engage with me by sight. To my delight, she began to respond. Within a few hours, I had her reaching out to take pieces of apple from my hand; within a week, she was reaching out to touch a small flashing light… Seven years later (as shown in the video below), she was running round a complex arena, deftly avoiding obstacles, picking up peanuts from the floor.

To anyone who’d observed Helen in 1972 – and didn’t know the history – it would have seemed that her eyesight was now quite normal. Yet, could she really ‘see everything’, as the New Scientist’s cover implied? I didn’t think so. I found it hard to put my finger on what was missing. But my hunch was that Helen herself still doubted she could see. She seemed strangely unsure of herself. If she was upset or frightened, her confidence would desert her, and she would stumble about as if in the dark again. The title I gave to my article inside the covers of the magazine was ‘Seeing and Nothingness’.

We were on the brink of a remarkable discovery. Following on from the findings with Helen, Weiskrantz took a new approach with a human patient, known by the initials DB, who, after surgery to remove a growth affecting the visual cortex on the left side of his brain, was blind across the right-half field of vision. In the blind area, DB himself maintained that he had no visual awareness. Nonetheless, Weiskrantz asked him to guess the location and shape of an object that lay in this area. To everyone’s surprise, he consistently guessed correctly. To DB himself, his success in guessing seemed quite unreasonable. So far as he was concerned, he wasn’t the source of his perceptual judgments, his sight had nothing to do with him. Weiskrantz named this capacity ‘blindsight’: visual perception in the absence of any felt visual sensations.

Blindsight is now a well-established clinical phenomenon. [And this perhaps explains why Ved Mehta, though blind, was able to run around easily at the school for the blind he attended in Arkansas, as he describes in his (fascinating) autobiography Face to Face. I always wondered about that. – LG]  When first discovered, it seemed theoretically shocking. No one had expected there could possibly be any such dissociation between perception and sensation. Yet, as I ruminated on the implications of it for understanding consciousness, I found myself doing a double-take. Perhaps the real puzzle is not so much the absence of sensation in blindsight as its presence in normal sight? If blindsight is seeing and nothingness, normal sight is seeing and somethingness. And surely it’s this something that stands in need of explanation.

Why do visual sensations, as experienced in normal vision, have the mysterious feel they do? Why is there any such thing as what philosophers call ‘phenomenal experience’ or qualia – our subjective, personal sense of interacting with stimuli arriving via our sense organs? Not only in the case of vision, but across all sense modalities: the redness of red; the saltiness of salt; the paininess of pain – what does this extra dimension of experience amount to? What’s it for? And, crucially, which animals besides ourselves experience it, which are sentient?

Sensation, let’s be clear, has a different function from perception. Both are forms of mental representation: ideas generated by the brain. But they represent – they are about – very different kinds of things. Perception – which is still partly intact in blindsight – is about ‘what’s happening out there in the external world’: the apple is red; the rock is hard; the bird is singing. By contrast, sensation is more personal, it’s about ‘what’s happening to me and how I as a subject evaluate it’: the pain is in my toe and horrible; the sweet taste is on my tongue and sickly; the red light is before my eyes and stirs me up.

It’s as if, in having sensations, we’re both registering the objective fact of stimulation and expressing our personal bodily opinion about it. But where do those extra qualitative dimensions come from? What can make the subjective present created by sensations seem so rich and deep, as if we’re living in thick time? What can the artist Wassily Kandinsky mean when he writes: ‘Colour is a power which directly influences the soul. Colour is the keyboard, the eyes are the hammers, the soul is the piano with many strings’? Why indeed do people use the strange expression ‘it’s like something to’ experience sensations? Is it because conscious sensations are like something they cannot really be? . . .

Continue reading. There’s quite a bit more.

Written by Leisureguy

3 October 2022 at 12:16 pm

The best foods to feed your gut microbiome

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It’s important to feed your gut microbiome good food because it feeds you. This Washington Post article (no paywall) by Anahad O’Connor provides a good summary of current knowledge.

Every time you eat, you are feeding trillions of bacteria, viruses and fungi that live inside your gut. But are you feeding them the right foods?

Scientists used to know very little about these communities of microbes that collectively make up the gut microbiota, also known as your gut microbiome. But a growing body of research suggests that these vast communities of microbes are the gateway to your health and well-being — and that one of the simplest and most powerful ways to shape and nurture them is through your diet.

Studies show that our gut microbes transform the foods we eat into thousands of enzymes, hormones, vitamins and other metabolites that influence everything from your mental health and immune system to your likelihood of gaining weight and developing chronic diseases.

Gut bacteria can even affect your mental state by producing mood-altering neurotransmitters like dopamine, which regulates pleasure, learning and motivation, and serotonin, which plays a role in happiness, appetite and sexual desire. Some recent studies suggest that the composition of your gut microbiome can even play a role in how well you sleep.

But the wrong mix of microbes can churn out chemicals that flood your bloodstream and build plaque in your coronary arteries. The hormones they produce can influence your appetite, blood sugar levels, inflammation and your risk of developing obesity and Type 2 diabetes.

The foods that you eat — along with your environment and your lifestyle behaviors — appear to play a much larger role in shaping your gut microbiome than genetics. In fact, genes have a surprisingly small effect. Studies show that even identical twins share just one third of the same gut microbes.

Your ‘good’ microbes feast on fiber and variety

In general, scientists have found that the more diverse your diet, the more diverse your gut microbiome. Studies show that a high level of microbiome diversity correlates with good health and that low diversity is linked to higher rates of weight gain and obesity, diabetesrheumatoid arthritis and other chronic diseases.

Eating a wide variety of fiber-rich plants and nutrient-dense foods seems to be especially beneficial, said Tim Spector, a professor of genetic epidemiology at King’s College London and the founder of the British Gut Project, a crowdsourced effort to map thousands of individual microbiomes.

Even if you already eat a lot of fruits and vegetables, Spector advises increasing the variety of plant foods you eat each week. One fast way to do this is to start using more herbs and spices. You can use a variety of leafy greens rather than one type of lettuce for your salads. Adding a variety of fruits to your breakfast, adding several different vegetables to your stir fry and eating more nuts, seeds, beans and grains is good for your microbiome. [See the Daily Dozen and Heber’s palette of colorful foods. – LG]

These plant foods contain soluble fiber that passes through much of your gastrointestinal tract largely unaffected until it reaches the large intestine. There, gut microbes feast on it, metabolizing and converting the fiber into beneficial compounds such as short chain fatty acids, which can lower inflammation and help to regulate your appetite and blood sugar levels.

In one study scientists followed more than 1,600 people for about a decade. They found that people who had the highest levels of microbial diversity also consumed higher levels of fiber. And they even gained less weight over the 10-year study, which was published in the International Journal of Obesity.

Clusters of ‘bad’ microbes thrive on junk food

Another important measure of gut health is a person’s ratio of beneficial microbes to potentially harmful ones. In a study of 1,100 people in the United States and Britain published last year in Nature Medicine, Spector and a team of scientists at Harvard, Stanford and other universities identified clusters of “good” gut microbes that protected people against cardiovascular disease, obesity and diabetes. They also identified clusters of “bad” microbes that promoted inflammation, heart disease and poor metabolic health.

While it’s clear that eating lots of fiber is good for your microbiome, research shows that eating the wrong foods can tip the balance in your gut in favor of disease-promoting microbes.

The Nature study found that “bad” microbes were more common in people who ate a lot of highly processed foods that are low in fiber and high in additives such as sugar, salt and artificial ingredients. This includes soft drinks, white bread and white pasta, processed meats, and packaged snacks like cookies, candy bars and potato chips.

The findings were based on an ongoing project called the Zoe Predict Study, the largest personalized nutrition study in the world. It’s led by . . .

Continue reading. (gift link, no paywall)

Written by Leisureguy

20 September 2022 at 5:41 pm

The Best Diet for Treating Atrial Fibrillation

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I don’t suffer from A-fib, and if I did, my pacemaker would be a big help, but I know some who do. This video is striking.

Written by Leisureguy

24 August 2022 at 6:19 am

Another Path to Intelligence

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James Bridle writes in Nautilus:

It turns out there are many ways of “doing” intelligence, and this is evident even in the apes and monkeys who perch close to us on the evolutionary tree. This awareness takes on a whole new character when we think about those non-human intelligences which are very different to us. Because there are other highly evolved, intelligent, and boisterous creatures on this planet that are so distant and so different from us that researchers consider them to be the closest things to aliens we have ever encountered: cephalopods.

Cephalopods—the family of creatures which contains octopuses, squids, and cuttlefish—are one of nature’s most intriguing creations. They are all soft-­bodied, containing no skeleton, only a hardened beak. They are aquatic, although they can survive for some time in the air; some are even capable of short flight, propelled by the same jets of water that move them through the ocean. They do strange things with their limbs. And they are highly intelligent, easily the most intel­ligent of the invertebrates, by any measure.

Octopuses in particular seem to enjoy demonstrating their intelli­gence when we try to capture, detain, or study them. In zoos and aquariums they are notorious for their indefatigable and often suc­cessful attempts at escape. A New Zealand octopus named Inky made headlines around the world when he escaped from the National Aquarium in Napier by climbing through his tank’s overflow valve, scampering eight feet across the floor, and sliding down a narrow, 106-­foot drainpipe into the ocean. At another aquarium near Dun­edin, an octopus called Sid made so many escape attempts, including hiding in buckets, opening doors, and climbing stairs, that he was eventually released into the ocean. They’ve also been accused of flood­ing aquariums and stealing fish from other tanks: Such tales go back to some of the first octopuses kept in captivity in Britain in the 19th century and are still being repeated today.

Otto, an octopus living in the Sea­Star Aquarium in Coburg, Germany, first attracted media attention when he was caught juggling hermit crabs. Another time he smashed rocks against the side of his tank, and from time to time would completely rearrange the contents of his tank “to make it suit his own taste better,” according to the aquar­ium’s director. One time, the electricity in the aquarium kept shorting out, which threatened the lives of other animals as filtration pumps ground to a halt. On the third night of the blackouts, the staff started taking night shifts sleeping on the floor to discover the source of the trouble—and found that Otto was swinging himself to the top of his tank, and squirting water at a low­-hanging bulb that seemed to be annoying him. He’d figured out how to turn the lights off.

Octopuses are no less difficult in the lab. They don’t seem to like being experimented on and try to make things as difficult as possible for researchers. At a lab at the University of Otago in New Zealand, one octopus discovered the same trick as Otto: It would squirt water at light bulbs to turn them off. Eventually it became so frustrating to have to continually replace the bulbs that the culprit was released back into the wild. Another octopus at the same lab took a personal dislike to one of the researchers, who would receive half a gallon of water down the back of the neck whenever they came near its tank. At Dal­housie University in Canada, a cuttlefish took the same attitude to all new visitors to the lab but left the regular researchers alone. In 2010, two biologists at the Seattle Aquarium dressed in the same clothes and played good cop/bad cop with the octopuses: One fed them every day, while the other poked them with a bristly stick. After two weeks, the octopuses responded differently to each, advancing and retreating, and flashing different colors. Cephalopods can recognize human faces.

All these behaviors—as well as many more observed in the wild—suggest that octopuses learn, remember, know, think, consider, and act based on their intelligence. This changes everything we think we know about “higher order” animals, because cephalopods, unlike apes, are very, very different to us. That should be evident just from the extraor­dinary way their bodies are constituted—but the difference extends to their minds as well.

Octopus brains are not situated, like ours, in their heads; rather, they are decentralized, with brains that extend throughout their bodies and into their limbs. Each of their arms contains bundles of neurons that act as independent minds, allowing them to move about and react of their own accord, unfettered by central control. Octopuses are a con­federation of intelligent parts, which means their awareness, as well as their thinking, occurs in ways which are radically different to our own.

Perhaps one of the fullest expressions of this difference is to be found, not in the work of scientists, but in a novel. In his book . . .

Continue reading.

Written by Leisureguy

18 August 2022 at 10:52 am

Posted in Evolution, Science

Why humans run the world

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Very interesting TED talk by Yuval Noah Harari. It seems to me that the cement that enables large-scale cooperation among humans is trust, and currently that is being diluted and undermined by those who exploit it selfishly.

What he calls “fictions” are, in my view, a variety of memes (cultural entities).

Also, interesting quotation:

We are social creatures to the inmost centre of our being. The notion that one can begin anything at all from scratch, free from the past, or unindebted to others, could not conceivably be more wrong.

-Karl Popper, philosopher and professor (28 Jul 1902-1994)

Written by Leisureguy

28 July 2022 at 2:34 pm

How flying snakes stay stable while gliding through the air

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I’m thinking this type of flying snake is worse than snakes on a plane.

Written by Leisureguy

14 July 2022 at 10:18 pm

Posted in Evolution, Science

How Did Consciousness Evolve? An Illustrated Guide

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Two posts back, I blogged an article on how the grand synthesis of evolutionary theory seemed to require some reworking. The MIT Press Reader has an article adapted from Simona Ginsburg and Eva Jablonka’s book Picturing the Mind: Consciousness Through the Lens of Evolution that reflects a similar view. That article begins:

What is consciousness, and who (or what) is conscious — humans, nonhumans, nonliving beings? Which varieties of consciousness do we recognize? In their book “Picturing the Mind,” Simona Ginsburg and Eva Jablonka, two leading voices in evolutionary consciousness science, pursue these and other questions through a series of “vistas” — over 65 brief, engaging texts, presenting some of the views of poets, philosophers, psychologists, and biologists, accompanied by Anna Zeligowski’s lively illustrations.

Each picture and text serves as a starting point for discussion. In the texts that follow, excerpted from the vista “How Did Consciousness Evolve?” the authors offer a primer on evolutionary theory, consider our evolutionary transition from nonsentient to sentient organisms, explore the torturous relation between learning studies and consciousness research, and ponder the origins and evolution of suffering and the imagination.


Evolutionary Theory

Evolutionary theory is a deceptively simple theory, which is why many people who have only a cursory acquaintance with it are nevertheless convinced that they fully understand it. Its basic assumptions are indeed simple. The first assumption, which was systematically explored first by Jean-Baptiste Lamarck and then by Charles Darwin, is that there was a single ancestor, or very few ancestors, of all living organisms. This is the principle of Descent with modification: all organisms are descended, with modifications, from ancestors that lived long ago.

The second principle, which is central to Darwin’s theory, is the principle of Natural selection: organisms with hereditary variations that render them better adapted to their local environment than others in their population leave behind more offspring. Darwin showed that this simple process, when applied recursively, can account for the evolution of complex organs like the eye, and, with the addition of some plausible auxiliary hypotheses, can explain the diversity of living species and their geographic distribution. In the last paragraph of “The Origin of Species by Means of Natural Selection,” Darwin summarized his ideas:

It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent on each other in so complex a manner, have all been produced by laws acting around us. These laws, taken in the largest sense, being Growth with reproduction; Inheritance which is almost implied by reproduction; Variability from the indirect and direct action of the external conditions of life, and from use and disuse; a Ratio of Increase so high as to lead to a Struggle for Life, and as a consequence to Natural Selection, entailing Divergence of Character and the Extinction of less- improved forms. Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone circling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.

Once he put forward his ideas, various scientists tried to crystallize and summarize Darwin’s view. For example, in the twentieth century, John Maynard Smith suggested that four basic processes underlie evolution by natural selection:

(i) Multiplication: an entity gives rise to two or more others.
(ii) Variation: not all entities are identical.
(iii) Heredity: like usually begets like. Variant X usually begets offspring X, but infrequently begets offspring Y.
(iv) Competition: some heritable variations affect the success of entities in persisting and multiplying more than others.

Although it sounds simple, when we unpack these processes, we appreciate how complex evolutionary theory actually is. There are multiple ways in which reproduction occurs and there are different types of inherited variations. Maynard Smith, like most 20th-century biologists, focused on DNA- based genetic variability, but since the early 2000s, the idea that variations in DNA drive all evolutionary change has been abandoned; it is now recognized that heritable variations in DNA, in patterns of gene expression, in behavior, and in culture are all important. Variation in these hereditary units can arise randomly or can be partially directed because heredity and development can be coupled. For example, stressful conditions during development can induce changes in gene expression that can be transmitted to the next generation. It has also been accepted that there are multiple targets and levels of selection within individuals, between individuals and between lineages, and that organisms have fuzzy boundaries. (Are the symbiotic bacteria in your gut part of you?) Crucially, organisms are not passive subjects of natural selection — they actively construct the environment in which they are selected and bequeath these ecological legacies to their offspring.

How, then, should evolutionary analysis proceed? We could start by tracing evolutionary change at the molecular-genetic, physiological-developmental, behavioral, or cultural levels. However, since organisms adjust to changing conditions in the external world and in their own genome by altering their behavior and physiology, cultural and behavioral adaptations frequently precede genetic changes and shape the conditions in which variations are selected. Genetic changes that stabilize or fine tune the behavioral or developmental changes follow. As evolutionary biologist Mary Jane West-Eberhard put it: “Genes are followers, not leaders, in evolution.”

In the 21st century, this integrative approach to evolutionary reasoning, which incorporates the effects of variations in DNA, development, behavior, and culture is being embraced by a growing number of biologists, including us.

Evolutionary Transitions

How should we think about the evolutionary transition from nonsentient to sentient organisms? There are several useful ways of carving up the living world and thinking about evolutionary transitions between forms and ways of life. Ecologists distinguish . . .

Continue reading.

Written by Leisureguy

29 June 2022 at 10:13 pm

Posted in Books, Evolution, Science

Do we need a new theory of evolution?

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Stephen Buranyi writes in the Guardian:

Strange as it sounds, scientists still do not know the answers to some of the most basic questions about how life on Earth evolved. Take eyes, for instance. Where do they come from, exactly? The usual explanation of how we got these stupendously complex organs rests upon the theory of natural selection.

You may recall the gist from school biology lessons. If a creature with poor eyesight happens to produce offspring with slightly better eyesight, thanks to random mutations, then that tiny bit more vision gives them more chance of survival. The longer they survive, the more chance they have to reproduce and pass on the genes that equipped them with slightly better eyesight. Some of their offspring might, in turn, have better eyesight than their parents, making it likelier that they, too, will reproduce. And so on. Generation by generation, over unfathomably long periods of time, tiny advantages add up. Eventually, after a few hundred million years, you have creatures who can see as well as humans, or cats, or owls.

This is the basic story of evolution, as recounted in countless textbooks and pop-science bestsellers. The problem, according to a growing number of scientists, is that it is absurdly crude and misleading.

For one thing, it starts midway through the story, taking for granted the existence of light-sensitive cells, lenses and irises, without explaining where they came from in the first place. Nor does it adequately explain how such delicate and easily disrupted components meshed together to form a single organ. And it isn’t just eyes that the traditional theory struggles with. “The first eye, the first wing, the first placenta. How they emerge. Explaining these is the foundational motivation of evolutionary biology,” says Armin Moczek, a biologist at Indiana University. “And yet, we still do not have a good answer. This classic idea of gradual change, one happy accident at a time, has so far fallen flat.”

There are certain core evolutionary principles that no scientist seriously questions. Everyone agrees that natural selection plays a role, as does mutation and random chance. But how exactly these processes interact – and whether other forces might also be at work – has become the subject of bitter dispute. “If we cannot explain things with the tools we have right now,” the Yale University biologist Günter Wagner told me, “we must find new ways of explaining.”

In 2014, eight scientists took up this challenge, publishing an article in the leading journal Nature that asked “Does evolutionary theory need a rethink?” Their answer was: “Yes, urgently.” Each of the authors came from cutting-edge scientific subfields, from the study of the way organisms alter their environment in order to reduce the normal pressure of natural selection – think of beavers building dams – to new research showing that chemical modifications added to DNA during our lifetimes can be passed on to our offspring. The authors called for a new understanding of evolution that could make room for such discoveries. The name they gave this new framework was rather bland – the Extended Evolutionary Synthesis (EES) – but their proposals were, to many fellow scientists, incendiary.

In 2015, the Royal Society in London agreed to host New Trends in Evolution, a conference at which some of the article’s authors would speak alongside a distinguished lineup of scientists. The aim was to discuss “new interpretations, new questions, a whole new causal structure for biology”, one of the organisers told me. But when the conference was announced, 23 fellows of the Royal Society, Britain’s oldest and most prestigious scientific organisation, wrote a letter of protest to its then president, the Nobel laureate Sir Paul Nurse. “The fact that the society would hold a meeting that gave the public the idea that this stuff is mainstream is disgraceful,” one of the signatories told me. Nurse was surprised by the reaction. “They thought I was giving it too much credibility,” he told me. But, he said: “There’s no harm in discussing things.”

Traditional evolutionary theorists were invited, but few showed up. Nick Barton, recipient of the 2008 Darwin-Wallace medal, evolutionary biology’s highest honour, told me he “decided not to go because it would add more fuel to the strange enterprise”. The influential biologists Brian and Deborah Charlesworth of the University of Edinburgh told me they didn’t attend because they found the premise “irritating”. The evolutionary theorist Jerry Coyne later wrote that the scientists behind the EES were playing “revolutionaries” to advance their own careers. One 2017 paper even suggested some of the theorists behind the EES were part of an “increasing post-truth tendency” within science. The personal attacks and insinuations against the scientists involved were “shocking” and “ugly”, said one scientist, who is nonetheless sceptical of the EES.

What accounts for the ferocity of this backlash? For one thing, this is a battle of ideas over the fate of one of the grand theories that shaped the modern age. But it is also a struggle for professional recognition and status, about who gets to decide what is core and what is peripheral to the discipline. “The issue at stake,” says Arlin Stoltzfus, an evolutionary theorist at the IBBR research institute in Maryland, “is who is going to write the grand narrative of biology.” And underneath all this lurks another, deeper question: whether the idea of a grand story of biology is a fairytale we need to finally give up.


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B
ehind the current battle over evolution lies a broken . . .

Continue reading.

And see also this earlier post. And see also “How Did Consciousness Evolve? An Illustrated Guide.”

Written by Leisureguy

29 June 2022 at 3:58 pm

Posted in Evolution, Science

How Parents’ Trauma Leaves Biological Traces in Children

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Rachel Yehuda, professor of psychiatry and neuroscience and director of the Center for Psychedelic Psychotherapy and Trauma Research at the Icahn School of Medicine at Mount Sinai, writes in Scientific American:

After the twin towers of the World Trade Center collapsed on September 11, 2001, in a haze of horror and smoke, clinicians at the Icahn School of Medicine at Mount Sinai in Manhattan offered to check anyone who’d been in the area for exposure to toxins. Among those who came in for evaluation were 187 pregnant women. Many were in shock, and a colleague asked if I could help diagnose and monitor them. They were at risk of developing post-traumatic stress disorder, or PTSD—experiencing flashbacks, nightmares, emotional numbness or other psychiatric symptoms for years afterward. And were the fetuses at risk?

My trauma research team quickly trained health professionals to evaluate and, if needed, treat the women. We monitored them through their pregnancies and beyond. When the babies were born, they were smaller than usual—the first sign that the trauma of the World Trade Center attack had reached the womb. Nine months later we examined 38 women and their infants when they came in for a wellness visit. Psychological evaluations revealed that many of the mothers had developed PTSD. And those with PTSD had unusually low levels of the stress-related hormone cortisol, a feature that researchers were coming to associate with the disorder.

Surprisingly and disturbingly, the saliva of the nine-month-old babies of the women with PTSD also showed low cortisol. The effect was most prominent in babies whose mothers had been in their third trimester on that fateful day. Just a year earlier a team I led had reported low cortisol levels in adult children of Holocaust survivors, but we’d assumed that it had something to do with being raised by parents who were suffering from the long-term emotional consequences of severe trauma. Now it looked like trauma leaves a trace in offspring even before they are born.

In the decades since, research by my group and others has confirmed that adverse experiences may influence the next generation through multiple pathways. The most apparent route runs through parental behavior, but influences during gestation and even changes in eggs and sperm may also play a role. And all these channels seem to involve epigenetics: alterations in the way that genes function. Epigenetics potentially explains why effects of trauma may endure long after the immediate threat is gone, and it is also implicated in the diverse pathways by which trauma is transmitted to future generations.

The implications of these findings may seem dire, suggesting that parental trauma predisposes offspring to be vulnerable to mental health conditions. But there is some evidence that the epigenetic response may serve as an adaptation that might help the children of traumatized parents cope with similar adversities. Or could both possible outcomes be true?

IN THE AFTERMATH

My first encounter with intergenerational transmission of trauma was in the 1990s, soon after my team documented high rates of PTSD among Holocaust survivors in my childhood community in Cleveland. The first study of its kind, it garnered a lot of publicity; within weeks I found myself heading a newly created Holocaust research center at Mount Sinai staffed largely by professional volunteers. The phone was ringing off the hook. The callers weren’t all Holocaust survivors, though; most were the adult children of Holocaust survivors. One particularly persistent caller—I’ll call him Joseph—insisted that I study people like him. “I’m a casualty of the Holocaust,” he claimed.

When he came in for an interview, Joseph didn’t look like a casualty of anything. A handsome and wealthy investment banker in an Armani suit, he could’ve stepped off the pages of a magazine. But Joseph lived each day with a vague sense that something terrible was going to happen and that he might need to flee or fight for his life. He’d been preparing for the worst since his early 20s, keeping cash and jewelry at hand and becoming proficient in boxing and martial arts. Lately he was tormented by panic attacks and nightmares of persecution, possibly triggered by reports of ethnic cleansing in Bosnia.

Joseph’s parents had met in a displaced-persons camp after surviving several years at Auschwitz, then arrived penniless in the U.S. His father worked 14 hours a day and said very little, never mentioning the war. But almost every night he woke the family with shrieks of terror from his nightmares. His mother spoke endlessly about the war, telling vivid bedtime stories about how relatives had been murdered before her eyes. She was determined that her son succeed, and his decision to remain unattached and childless infuriated her. “I didn’t survive Auschwitz so that my own child would end the family line,” she’d say. “You have an obligation to me and to history.”

We ended up talking to many people like Joseph: adult children of Holocaust survivors who suffered from anxiety, grief, guilt, dysfunctional relationships and intrusions of Holocaust-related imagery. Joseph was right—I needed to study people like him. Because those who were calling us were (in research-speak) self-selecting, we decided to evaluate the offspring of the Holocaust survivors we had just studied in Cleveland. The results were clear. Survivors’ adult children were more likely than others to have mood and anxiety disorders, as well as PTSD. Further, many Holocaust offspring also had low cortisol levels—something that we had observed in their parents with PTSD.

FIGHT, FLIGHT—OR FREEZE

What did it all mean? Unraveling the tangle of trauma, cortisol and PTSD has occupied me and many other researchers for the decades since. In the classic fight-or-flight response, identified in the 1920s, a threatening encounter triggers the release of stress hormones such as adrenaline and cortisol. The hormones prompt a cascade of changes, such as quickening the pulse and sharpening the senses to enable the threatened person or animal to focus on and react to the immediate danger. These acute effects were believed to dissipate once the danger receded.

In 1980, however, psychiatrists and other advocates for Vietnam War veterans won a prolonged struggle to get post-traumatic stress included in the third edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III). It was the first official recognition that trauma could have long-lasting effects. But the diagnosis was controversial. Many psychologists believed that its inclusion in the DSM-III had been politically, rather than scientifically, driven—in part because there were no scientific explanations for how a threat could continue to influence the body long after it was removed.

Complicating matters, studies of Vietnam veterans were generating perplexing results. In the mid-1980s  . . .

Continue reading.

And see also this later post.

Written by Leisureguy

29 June 2022 at 11:43 am

Glimpses of almost-humans from prehistory

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Matt Webb has a fascinating post at Interconnected. It consists of multiple parts. Here’s the first and part of the second:

1.

Cave art may be inaccessible to today’s brain:

A recent article argued that superior visual perception was necessary for the creation of Paleolithic cave paintings because of the level of correct anatomical details and accurate depictions of high-speed leg positions of animals in motion, considering that the works were accomplished far removed from the actual animals and with crude tools. The article uncovered and outlined current evidence for an association between visual thinkers (some diagnosed within the Autism Spectrum Disorder) and a relatively high percentage of archaic genes, of which some are associated with perception and cognition. Moreover, within this group are some savants who can quickly and accurately scan what they see and reproduce it artistically in extraordinary detail. One example is reproducing the correct number and relative size of windows from a brief exposure to a city scene. However, the linguistic abilities of visual thinkers may be impaired, which suggests a negative correlation between visual perception/memory and language.

Brain Sciences
“Is Reduced Visual Processing the Price of Language?”
Go to text 

The argument in the paper is that pre-human primates (a) are sometimes superior to humans in dealing with visual sequences, but (b) have brain areas more directly connected to visual processing than humans. They deal with a flood of visual information – versus humans, which abstract and discard.

The paper goes on to suggest that language emerged relatively recently… and the emergence of language may be associated with the reduced brain size in Homo sapiens that started about 50,000 years ago and more markedly 10,000 years ago.

(I hadn’t realised that there was such an observed brain size reduction occurring so recently. The early known city is only 9,000 years ago! Radical changes in the nature of consciousness in the shallows of pre-history.)

We suggest that an effect of this loss in brain size was the reduction of neuronal signaling and/or pathways related to raw perception and vision in particular. Visual perception relies on informational highways that may provide so much information that it can be overwhelming for other brain functions, such as retrieving knowledge appropriate to the situation or imagining something that is not present in the here and now. We hypothesize that the loss in brain volume is mainly linked to reduced perception of detail in space and time. We are no longer able to perceive how many hooves of a running horse touch the ground, as the cave artists of Chauvet may have seen with ease.

After the Upper Palaeolithic (50,000 to 10,000 years ago) we no longer find evidence for elaborate realistic cave paintings (although we find iconic and symbolic cave paintings after this period).

Ref.

Johansson, C., & Folgerø, P. O. (2022). Is Reduced Visual Processing the Price of Language? Brain Sciences, 12(6), 771

2.

Guide to Machine Elves and Other DMT Entities.

Self-transforming machines elves: a term coined by the ethnobotanist, philosopher, and writer Terence McKenna to describe some of the entities that are encountered in a DMT trip. They’ve come to be known by many names, including “clockwork elves”, “DMT elves”, “fractal elves”, and “tykes”.

McKenna:

During my own experiences smoking synthesized DMT in Berkeley, I had had the impression of bursting into a space inhabited by merry elfin, self-transforming, machine creatures. Dozens of these friendly fractal entities, looking like self-dribbling Faberge eggs on the rebound, had surrounded me and tried to teach me the lost language of true poetry.

Meetings are common:

Philip Mayer collected and analyzed 340 DMT trip reports in 2005. Mayer found that 66% of them (226) referenced independently-existing entities that interact in an intelligent and intentional manner.

RELATED #1:

My trip to the dentist which had me discover the secret of the universe (2020) which turns out to be a common effect of nitrous.

RELATED #2:

Charles Bonnet syndrome, in which . . .

Continue reading.

Written by Leisureguy

22 June 2022 at 7:24 pm

Origin of the Cyclops

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A Facebook post from History Cool Kids:

The fossil skulls of Pleistocene dwarf elephants scattered throughout the coastal caves in Italy and the Greek islands, most likely inspired the one-eyed Cyclopes in ancient Greek mythology.

During the Pleistocene ice age (2,580,000 to 11,700 years ago), land bridges emerged that allowed ancient elephants to move to emerging islands to escape predators and/or find new food sources. As sea levels began to rise around the Mediterranean, these ancient elephants became trapped and had to compete for limited amounts of food. According to the island rule, mammals tend to shrink or grow depending on the availability of resources in their environment.

The isolated ancient elephants evolved into different species depending on the island they found themselves on. The ones that were found on Cyprus were approximately 6 feet tall, nearly double the size than the ones found on Sicily and Malta. The ancient elephants lived in relative peace until humans found their way to the islands approximately 11,000 years ago. Within a century, they were over-hunted and became extinct.

By the time the Romans and Greeks came to occupy the Mediterranean islands, all that remained were skulls that were twice the size of those belonging to humans. These massive skulls also had a single hole right in the center that the Greeks and Romans mistakenly believed was an eye socket. It was in fact, a socket that was connected to the trunk of an ancient elephant.

Source 

Written by Leisureguy

19 June 2022 at 3:23 pm

Posted in Books, Evolution, Science

Google engineer thinks the company’s AI has come to life

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Nitasha Tiku has an interesting article (gift link, no paywall) in the Washington Post. It begins:

Google engineer Blake Lemoine opened his laptop to the interface for LaMDA, Google’s artificially intelligent chatbot generator, and began to type.

“Hi LaMDA, this is Blake Lemoine … ,” he wrote into the chat screen, which looked like a desktop version of Apple’s iMessage, down to the Arctic blue text bubbles. LaMDA, short for Language Model for Dialogue Applications, is Google’s system for building chatbots based on its most advanced large language models, so called because it mimics speech by ingesting trillions of words from the internet.

“If I didn’t know exactly what it was, which is this computer program we built recently, I’d think it was a 7-year-old, 8-year-old kid that happens to know physics,” said Lemoine, 41.

Lemoine, who works for Google’s Responsible AI organization, began talking to LaMDA as part of his job in the fall. He had signed up to test if the artificial intelligence used discriminatory or hate speech.

As he talked to LaMDA about religion, Lemoine, who studied cognitive and computer science in college, noticed the chatbot talking about its rights and personhood, and decided to press further. In another exchange, the AI was able to change Lemoine’s mind about Isaac Asimov’s third law of robotics.

Lemoine worked with a collaborator to present evidence to Google that LaMDA was sentient. But Google vice president Blaise Aguera y Arcas and Jen Gennai, head of Responsible Innovation, looked into his claims and dismissed them. So Lemoine, who was placed on paid administrative leave by Google on Monday, decided to go public.

Google hired Timnit Gebru to be an outspoken critic of unethical AI. Then she was fired for it.

Lemoine said that people have a right to shape technology that might significantly affect their lives. “I think this technology is going to be amazing. I think it’s going to benefit everyone. But maybe other people disagree and maybe us at Google shouldn’t be the ones making all the choices.”

Lemoine is not the only engineer who claims to have seen a ghost in the machine recently. The chorus of technologists who believe AI models may not be far off from achieving consciousness is getting bolder.

Aguera y Arcas, in an article in the Economist on Thursday featuring snippets of unscripted conversations with LaMDA, argued that neural networks — a type of architecture that mimics the human brain — were striding toward consciousness. “I felt the ground shift under my feet,” he wrote. “I increasingly felt like I was talking to something intelligent.”

In a statement, Google spokesperson Brian Gabriel said: “Our team — including ethicists and technologists — has reviewed Blake’s concerns per our AI Principles and have informed him that the evidence does not support his claims. He was told that there was no evidence that LaMDA was sentient (and lots of evidence against it).”

Today’s large neural networks produce captivating results that feel close to human speech and creativity because of advancements in architecture, technique, and volume of data. But the models rely on pattern recognition — not wit, candor or intent.

Though other organizations have developed and already released similar language models, we are taking a restrained, careful approach with LaMDA to better consider valid concerns on fairness and factuality,” Gabriel said.

In May, Facebook parent Meta opened its language model to academics, civil society and government organizations. Joelle Pineau, managing director of Meta AI, said it’s imperative that . . .

Continue reading (gift link, no paywall).

Written by Leisureguy

11 June 2022 at 2:38 pm

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