https://www.brainpickings.org/2016/09/26/the-hidden-life-of-trees-peter-wohlleben/
Related: a lire et classerWATCH: There's a genetic reason why some people sneeze in the sunshine - ScienceAlert Like many of us, Derek Muller, host of the YouTube channel Veritasium, has a condition known as a photic sneeze reflex. The condition affects roughly one in four of us, and makes us sneeze whenever we go from a darker room into the sunshine. Research into the genetics underlying photic sneeze reflex has found that just one letter's difference in our DNA code can determine if someone is a Sun sneezer or not - but we still don't know why humans have evolved such a strange anomaly. The variation is known as a single nucleotide polymorphism, or SNP: a spot where our DNA code varies slightly. And the result can actually trigger the unique photic sneeze reflex, as Derek explains in the video below:
Un rite mystérieux chez les chimpanzés En Afrique de l'ouest, et seulement là, des chimpanzés ont une drôle d'habitude : ils jettent de lourdes pierres contre un arbre, toujours le même. La signification de ce comportement est énigmatique. Les découvreurs, qui l'ont décrit en 2016, pensent qu'il est peut-être de la même nature que les rituels humains.
How dark matter became a particle It took decades for dark matter to enter the lexicon of particle physics. Today, explaining the nature and abundance of dark matter is one of the most pressing problems in the field. Résumé Comment la matière noire est devenue une particule La matière noire, prédite dans les années 1930, est essentielle dans notre connaissance de l’Univers. We Have Weird New Details On The Strangest Symbiotic Relationship Ever Found Back in 2011, scientists discovered the world's only known example of a vertebrate cell hosting the cells of a completely different species in an act of symbiosis between a salamander and a species of algae. While similar relationships can be found in animals without a backbone, such as coral and molluscs, this unusual discovery posed a bunch of questions about how the partnership is even possible in a vertebrate, and who it's benefiting. Now, thanks to a new study, we're starting to get some answers - and it's not pretty.
Here's what Cassini heard as it made its daring dive between Saturn and its rings - ImaGeo A Simon and Garfunkel song comes to mind—and that has scientists scratching their heads as the spacecraft heads today for a second dive. In this illustration, the Cassini spacecraft is shown diving between Saturn and the planet’s innermost ring. (Source: NASA/JPL-Caltech) As the Cassini spacecraft swooped between Saturn and its innermost ring on April 26th, one of its instruments listened for the sounds of its passage through the heretofore unexplored region. What it heard was of great interest to engineers planning for the second dive, as well as to scientists who study Saturn’s rings.
The Brain Has Its Own "Autofill" Function for Speech The world is an unpredictable place. But the brain has evolved a way to cope with the everyday uncertainties it encounters—it doesn’t present us with many of them, but instead resolves them as a realistic model of the world. The body’s central controller predicts every contingency, using its stored database of past experiences, to minimize the element of surprise. Take vision, for example: We rarely see objects in their entirety but our brains fill in the gaps to make a best guess at what we are seeing—and these predictions are usually an accurate reflection of reality.
Reached Via a Mind-Reading Device, Deeply Paralyzed Patients Say They Want to Live - MIT Technology Review In 1995, Jean-Dominique Bauby suffered a massive stroke that left him paralyzed and speechless, with only the ability to blink his left eyelid. Using just that eye, he silently dictated his memoir, The Diving Bell and the Butterfly, later adapted into a film. Bauby suffered from “locked-in syndrome,” in which patients are completely paralyzed except for some eye movement. Some patients eventually lose even the ability to blink, cutting off all contact with the world and raising questions of whether they are still fully conscious and, if so, whether they still wish to live.
This new gene map could force a rethink of how vertebrate brains evolved As complex as the human brain is, it more or less has the same fundamental structure as most other backboned animals - which means it can be divided into three general regions: forebrain, midbrain, and hindbrain. Researchers have long thought that these three sections all evolved from three simpler versions in our vertebrate ancestors. But a new map of the genes being activated in the brains of a tiny fish-like animal suggests that's not the case, and it could force us to revise our assumptions about how vertebrate brains evolved.
Le cerveau humain depuis le paléolithique- Hominidés Evolution et taille du cerveau des hominidés Comment mesurer le cerveau de l’homme moderne et de ses ancêtres ? Mesurer les cerveaux ce n’est pas mesurer l’intelligence ! Pour évaluer et comparer un cerveau il existe plusieurs méthodes. La première consiste à littéralement peser l’encéphale et à lui attribuer un poids en calculant la moyenne selon l'espèce. En moyenne, chez l’homme moderne, le cerveau pèse 1,4 kg.
Medical Xpress: Neurons' faulty wiring leads to serotonin imbalance, depression-like behavior in mice Columbia scientists have identified a gene that allows neurons that release serotonin—a neurotransmitter that regulates mood and emotions—to evenly spread their branches throughout the brain. Without this gene, these neuronal branches become entangled, leading to haphazard distribution of serotonin, and signs of depression in mice. These observations shed light on how precise neuronal wiring is critical to overall brain health, while also revealing a promising new area of focus for studying psychiatric disorders associated with serotonin imbalance—such as depression, bipolar disorder, schizophrenia and autism. The findings were published today in Science. "By pinpointing the genes that guide the organization of neurons, we can draw a line between changes to those genes, and the cellular, circuitry and behavioral deficiencies that can occur as a result," said Tom Maniatis, PhD, a principal investigator at Columbia's Mortimer B.
"Origin of the Universe Riddle Solved- and,er, It Wasn't God" Claim Canadian Physicists A Group of researchers have made what may turn out to be the most significant discovery in HISTORY – how the cosmos came into being from nothing. The immense question has concerned religions, philosophers and researchers since the dawn of time but now a Canadian group of scientists consider that they have finally solved this riddle. And the results are so convincing they even challenge the need for religion, or in any case an omnipotent creator – the foundation of all world religions. Man Missing Most Of His Brain Challenges Everything We Thought We Knew About Consciousness Yet miraculously, the man was not only fully conscious, but lived a rich and unhindered life, working as a civil servant and living with his wife and two kids, blissfully unaware of the gaping hole in his brain. His ability to function without so many of the key brain regions previously considered vital for consciousness raises some major questions about existing theories regarding how the brain works and the mechanisms underlying our awareness. For example, neuroscientists have often asserted that a brain region called the thalamus, which relays sensory signals to the cerebral cortex, is indispensable for consciousness. This is because research has indicated that damage to the thalamus often causes people to fall into a coma, while one team of scientists were even able to manually “switch off” an epileptic patient’s consciousness by electrically stimulating this brain region. Image: A brain region called the thalamus has been shown to be vital for consciousness to exist.
Medical Xpress: Better memory makes people tire of experiences more quickly We're fickle creatures. At least if we can remember to be, according to a new study led by a University of Kansas researcher of marketing and consumer behavior. "People with larger working memory capacities actually encode information more deeply," said Noelle Nelson, lead author of the research published in the Journal of Consumer Research. "They remember more details about the things they've experienced, and that leads them to feel like they've had it more. That feeling then leads to the large capacity people getting tired of experiences faster."
L'érotisme (2/4) : Philosophie du sexe Il y a toujours, comme le disait Diderot, "un peu de testicule au fond de nos sentiments les plus purs" ; l'érotisme se déploie dans cette dualité entre humanité et bestialité par laquelle l'érotisme est le propre de l'homme. Pourquoi se cache-t-on généralement pour faire l'amour ? Même quand on est athée, le sexe a "un petit goût de péché", il y a toujours une part de transgression. Mais cela suffit-il à définir l'érotisme ? Il y a notamment chez Georges Bataille une mystique du sexe qui fait parfois perdre la dimension triviale, profane et concrète de la relation érotique, selon notre invité André Comte-Sponville.