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sissij

Your Dog Remembers More Than You Think - The New York Times - 0 views

www.nytimes.com/...dogs-memory.html

brain science language research

shared by sissij on 24 Nov 16 - No Cached
  • In people it is called episodic memory, and it involves a sense of self. In animals, it’s called episodic-like memory, because it’s difficult to try to plumb something as elusive as self without the aid of language.
  • Dr. Fugazza and colleagues reported online in Current Biology that this showed that the dogs remembered an event they hadn’t been concentrating on, the trainer’s action. She said one aspect strengthened that conclusion: The dogs tended to lie down immediately when they got back to the mat, suggesting that their heads were in “lie down” mode, not “do it” mode.
  • He said human episodic memory is lost in Alzheimer’s disease and he and others study animal memory in hopes of learning how to combat that loss. The work on dogs offers a new technique that could be very useful, he said.
  • sissij on 24 Nov 16
     
    I found this experiment very interesting because it shows some aspect of how animals memory works. The result can be used to see how memory work without language. I think language and memory have an intertwined relationship because sometimes I can feel that the information stored in my brain is in language rather than abstract form such as knowledge. For example, my memory of chemistry knowledge is stored in English, so when I am reading a chemistry related book in Chinese, I would usually get lost because there aren't any vocals on Chemistry in Chinese in my memory. It would be a very interesting question to consider that how our memory will construct if we don't have a language. There is a kind of mental disease called "aphasia", meaning the loss of ability to understand language. How do they remember things when they lose the ability to assign meanings and communicate? --Sissi (11/24/2016)
sissij

Language family - Wikipedia - 0 views

en.wikipedia.org/...Language_family

language knowledge wikipedia

shared by sissij on 26 Nov 16 - No Cached
  • A language family is a group of languages related through descent from a common ancestor, called the proto-language of that family. The term 'family' reflects the tree model of language origination in historical linguistics, which makes use of a metaphor comparing languages to people in a biological family tree, or in a subsequent modification, to species in a phylogenetic tree of evolutionary taxonomy.
  • the Celtic, Germanic, Slavic, Romance, and Indo-Iranian language families are branches of a larger Indo-European language family. There is a remarkably similar pattern shown by the linguistic tree and the genetic tree of human ancestry[3] that was verified statistically.
  • A speech variety may also be considered either a language or a dialect depending on social or political considerations. Thus, different sources give sometimes wildly different accounts of the number of languages within a family. Classifications of the Japonic family, for example, range from one language (a language isolate) to nearly twenty.
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  • A language isolated in its own branch within a family, such as Armenian within Indo-European, is often also called an isolate, but the meaning of isolate in such cases is usually clarified. For instance, Armenian may be referred to as an "Indo-European isolate". By contrast, so far as is known, the Basque language is an absolute isolate: it has not been shown to be related to any other language despite numerous attempts.
  • The common ancestor of a language family is seldom known directly since most languages have a relatively short recorded history. However, it is possible to recover many features of a proto-language by applying the comparative method, a reconstructive procedure worked out by 19th century linguist August Schleicher.
  • sissij on 26 Nov 16
     
    I found this metaphor very accurate because I think languages certainly have some intimate relationship like family members. Languages are not all very different from one another and isolated. Although people speaking different language may not understand one another, their languages are still connected. I think this article can show that language in some ways are connected like bridges instead of walls. --Sissi (11/26/2016)
sissij

Depression is as bad for your heart as high cholesterol | Fox News - 0 views

www.foxnews.com/...heart-as-high-cholesterol.html

fox news brain science science

shared by sissij on 30 Jan 17 - No Cached
  • When you think of heart attacks, you might assume the most common causes are smoking, high cholesterol, or obesity. Mental health issues probably don't spring to mind.
  • Depression—which for this study, was determined by a checklist of mood symptoms, including anxiety and fatigue
  • “depressed mood and exhaustion holds a solid middle position within the concert of major cardiovascular risk factors.”
  • sissij on 30 Jan 17
     
    I think it is really interesting that even mental health issues has a positive relationship with cardiovascular disease. Our mind can affect how our body works. As we learn in the sense and perception unit, we know that brain will give us a shot of certain chemical that makes us feel good when we make certain decision. I think how we feel can reflect how our body feels. We all know that we feel pain because it is a warning that the injured part of our body send to our brain. So I think probably the feeling of depressed can be a warning sent by some part of our body. The scientific method mentioned in this article is a population research which is a typical biology scientific method. --Sissi (1/29/2017)
Javier E

Psychiatry's New Guide Falls Short, Experts Say - NYTimes.com - 1 views

www.nytimes.com/...e-falls-short-experts-say.html

psychiatry guide science mental paradigm diagnosis causes brain science psychology knowledge

shared by Javier E on 07 May 13 - No Cached
  • his goal was to reshape the direction of psychiatric research to focus on biology, genetics and neuroscience so that scientists can define disorders by their causes, rather than their symptoms.
  • While the Diagnostic and Statistical Manual of Mental Disorders, or D.S.M., is the best tool now available for clinicians treating patients and should not be tossed out, he said, it does not reflect the complexity of many disorders, and its way of categorizing mental illnesses should not guide research.
  • senior figures in psychiatry who have challenged not only decisions about specific diagnoses but the scientific basis of the entire enterprise. Basic research into the biology of mental disorders and treatment has stalled, they say, confounded by the labyrinth of the brain.
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  • The creators of the D.S.M. in the 1960s and ’70s “were real heroes at the time,” said Dr. Steven E. Hyman, a psychiatrist and neuroscientist at the Broad Institute and a former director at the National Institute of Mental Health. “They chose a model in which all psychiatric illnesses were represented as categories discontinuous with ‘normal.’ But this is totally wrong in a way they couldn’t have imagined. So in fact what they produced was an absolute scientific nightmare. Many people who get one diagnosis get five diagnoses, but they don’t have five diseases — they have one underlying condition.”
  • Dr. Insel is one of a growing number of scientists who think that the field needs an entirely new paradigm for understanding mental disorders, though neither he nor anyone else knows exactly what it will look like.
  • Decades of spending on neuroscience have taught scientists mostly what they do not know, undermining some of their most elemental assumptions. Genetic glitches that appear to increase the risk of schizophrenia in one person may predispose others to autism-like symptoms, or bipolar disorder. The mechanisms of the field’s most commonly used drugs — antidepressants like Prozac, and antipsychosis medications like Zyprexa — have revealed nothing about the causes of those disorders. And major drugmakers have scaled back psychiatric drug development, having virtually no new biological “targets” to shoot for.
  • Dr. Hyman, Dr. Insel and other experts said they hoped that the science of psychiatry would follow the direction of cancer research, which is moving from classifying tumors by where they occur in the body to characterizing them by their genetic and molecular signatures.
  • Dr. Insel said in the interview that his motivation was not to disparage the D.S.M. as a clinical tool, but to encourage researchers and especially outside reviewers who screen proposals for financing from his agency to disregard its categories and investigate the biological underpinnings of disorders instead.
sissij

The Stem-Cell Revolution Is Coming - Slowly - The New York Times - 3 views

www.nytimes.com/...hinya-yamanaka-stem-cells.html

new york times science social media

shared by sissij on 17 Jan 17 - No Cached
  • In 2001, President George W. Bush issued an executive order banning federal funding for new sources of stem cells developed from preimplantation human embryos. The action stalled research and discouraged scientists.
  • re-energized the field by devising a technique to “reprogram” any adult cell, such as a skin cell, and coax it back to its earliest “pluripotent” stage. From there it can become any type of cell, from a heart muscle cell to a neuron.
  • But it’s a double-edged sword. After multiple cell cycles, the chances of mutations increases.
  • sissij on 17 Jan 17
     
    In Biology, we learned that the study for stem cells has been halted because of the ethic issues on whether embryos should be count as human life. Now, there is this new technique that can induce skin cello its earliest "pluripotent" stage. With this technique,the study of stem cells and continue and flourish to benefit patients who need to have new cells that aren't mutated. It's surprised to see that how fast science is progressing. The science wielder at school might not be the science up to date.--Sissi (1/17/2017)
sissij

How humans bond: The brain chemistry revealed: New research finds that dopamine is invo... - 0 views

www.sciencedaily.com/...170217160940.htm

science research brain science

shared by sissij on 21 Feb 17 - No Cached
  • Northeastern University psychology professor Lisa Feldman Barrett found, for the first time, that the neurotransmitter dopamine is involved in human bonding, bringing the brain's reward system into our understanding of how we form human attachments.
  • To conduct the study, the researchers turned to a novel technology: a machine capable of performing two types of brain scans simultaneously -- functional magnetic resonance imaging, or fMRI, and positron emission tomography, or PET.
  • Barrett's team focused on the neurotransmitter dopamine, a chemical that acts in various brain systems to spark the motivation necessary to work for a reward.
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  • The mothers who were more synchronous with their own infants showed both an increased dopamine response when viewing their child at play and stronger connectivity within the medial amygdala network.
  • sissij on 21 Feb 17
     
    I think this article is very interesting because it is trying to explain human social behaviors through chemistry and biology. Although there are a lot of factors in human science, by converting it to a natural science problem, we can make the question easier to answer. It also shows the interaction between different subfields of science. --Sissi (2/20/2017)
sissij

First-born children have better thinking skills, study says | Society | The Guardian - 0 views

www.theguardian.com/...ter-thinking-skills-study-says

the guardian science research

shared by sissij on 09 Feb 17 - No Cached
  • They may be jokingly referred to as PFBs – precious first borns – on popular parenting websites, but a study says first-born children really do reap the benefits of being number one.
  • the first-born generally received more help with tasks that develop thinking skills.
  • The study found parents changed their behaviour as they had more children, giving less mental stimulation and taking part in fewer activities like reading with the child, crafts and playing musical instruments.
  • sissij on 09 Feb 17
     
    I find this research interesting. In this research, the researchers did a population observation, which is similar to the population method mentioned in evolutionary biology. The author also discussed a lot of hypothesis why the first born child tends to have better thinking skills. The author don't have direct evidence pointing to his hypothesis, the tendency is a fact. Although there are a lot of uncertainties in this research, this result might appeal to many first born children and make them feel a little more superior. --Sissi (2/9/2017)
Maria Delzi

How Life Began: New Clues | TIME.com - 0 views

science.time.com/...egan-new-clues-from-new-worlds

shared by Maria Delzi on 17 Jan 14 - No Cached
  • Astronomers recently announced that there could be an astonishing 20 billion Earthlike planets in the Milky Way
  • How abundant life actually is, however, hinges on one crucial factor: given the right conditions and the right raw materials,
  • what is the mathematical likelihood that life will actually would arise?
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  • biology would have to be popping up all over the place.
  • Andrew Ellington, of the Center for Systems and Synthetic Biology at the University of Texas, Austin, “I can’t tell you what the probability is. It’s a chapter of the story that’s pretty much blank.”
  • Given that rather bleak-sounding assessment, it may be surprising to learn that Ellington is actually pretty upbeat. But that’s how he and two colleagues come across in a paper in the latest Science. The crucial step from nonliving stuff to a live cell is still a mystery, they acknowledge, but the number of pathways a mix of inanimate chemicals could have taken to reach the threshold of the living turns out to be many and varied. “It’s difficult to say exactly how things did occur,” says Ellington. “But there are many ways it could have occurred.
  • The first stab at answering the question came all the way back in the 1950s, when chemists Stanley Miller and Harold Urey passed an electrical spark through a beaker containing methane, ammonia, water vapor and hydrogen, thought at the time to represent Earth’s primordial atmosphere.
  • Scientists have learned so much, in fact, that the number of places life might have begun has grown to include such disparate locations as the hydrothermal vents at the bottom of the ocean; beds of clay; the billowing clouds of gas emerging from volcanoes; and the spaces in between ice crystals.
  • The number of ideas about how the key step from organic chemicals to living organisms might have been taken has multiplied as well: there’s the “RNA world hypothesis” and the “lipid world hypothesis” and the “iron-sulfur world hypothesis” and more, all of them dependent on a particular set of chemical circumstances and a particular set of dynamics and all highly speculative.
  • “Maybe when they do,” says Ellington, “we’ll all do a face-plant because it turns out to be so obvious in retrospect.” But even if they succeed, it will only prove that a manufactured cell could represent the earliest life forms, not that it actually does. “It will be a story about what we think might have happened, but it will still be a story.”
  • The story Ellington and his colleagues have been able to tell already, however, is a reason for optimism. We still don’t know the odds that life will arise under the right conditions. But the underlying biochemistry is abundantly, ubiquitously available—and it would take an awfully perverse universe to take things so far only to shut them down at the last moment.
carolinewren

'God made science': Louisiana teachers are literally using the Bible as science textboo... - 0 views

www.rawstory.com/...ce-textbooks-in-public-schools

science god schools

shared by carolinewren on 03 Jun 15 - No Cached
  • students in Louisiana literally use the Bible as their science textbook, according to recently obtained records
  • State law permits teachers to promote classroom discussion on evolution, but critics say the Louisiana Science Education Act allows creationism to be taught in public schools.
  • students read the Book of Genesis to learn creationism in biology class.
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  • “We will read in Genesis and them [sic] some supplemental material debunking various aspects of evolution from which the students will present,”
  • A teacher at Caddo Parish schools wrote a newspaper column saying that her job is to present both evolution and creationism.
  • God made science,” wrote fifth-grade teacher Charlotte Hinson.
  • “pushing her twisted religious beliefs onto the class,” another praised biology teacher Michael Stacy because he “discussed evolution and creationism in a full spectrum of thought.”
  • state law, passed in 2008, allows science teachers to introduce supplemental materials to “critique” scientific theories – lessons on creationism are still illegal under federal law.
  • schools are also violating prohibitions on teacher-led prayer in school.
carolinewren

Louisiana science education: School boards, principals, and teachers endorse creationis... - 0 views

www.slate.com/...pals_and_teachers_endorse.html

louisiana science education

shared by carolinewren on 03 Jun 15 - No Cached
  • For some Louisiana public school students, their science textbook is the Bible, and in biology class they read the Book of Genesis to learn the “creation point of view.”
  • In another email exchange with Rowland, a parent had complained that a different teacher, Cindy Tolliver, actually taught that evolution was a “fact.” This parent complained that Tolliver was “pushing her twisted religious beliefs onto the class.” Principal Rowland responded, “I can assure you this will not happen again.” Advertisement
  • permits science teachers to use supplemental materials to “critique” evolution, opening a backdoor that these teachers are using, as intended, to teach creationism. Such lessons are allowed under this Louisiana law, but they are illegal under federal law
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  • one in eight high school biology teachers advocate for creationism, even though it's unconstitutional,”
  • many teachers are interpreting the Louisiana Science Education Act as allowing such unconstitutional and scientifically-misleading lessons.”
carolinewren

If Evolution Has Implications for Religion, Can We Justify Teaching It in Public School... - 0 views

www.evolutionnews.org/...if_evolution_ha096541.html

evolution religion teaching

shared by carolinewren on 03 Jun 15 - No Cached
  • Evolutionary biology is a science, so it can be legally taught in public schools when it's treated as a science and isn't promoted as a support for atheism or materialism.
  • few would deny that Darwinian evolution has larger implications that aren't friendly to theism
  • the Court held in Lynch v. Donnelly that "not every law that confers an indirect, remote, or incidental benefit upon [religion] is, for that reason alone, constitutionally invalid"
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  • Do the larger religious (or anti-religious) implications of a scientific theory make it inadmissible for instruction in public schools? They shouldn't.
  • just because we're declaring the teaching of evolution to be constitutional doesn't mean we that it has no connections to religion
  • while it may sound odd to hear that we can (sometimes) declare something constitutional to teach in public schools even though it touches upon religion, there's good legal precedent for such a finding.
  • a government policy establishes religion if its "principal or primary effect" is one that "advances or inhibits" religion.
  • the statute must have a secular legislative purpose; second, its principal or primary effect must be one that neither advances nor inhibits religion; finally, the statute must not foster an excessive government entanglement with religion
  • a government policy is unconstitutional if it has a "primary" or "principal" effect that advances (or inhibits) religion. However, in light of this second part, the Supreme Court has also developed a legal doctrine called the "incidental effects" or "secondary effects" doctrine which says that government law or policy may have "secondary" or "incidental" effects that touch upon religion and not violate the Establishment Clause.
  • Secondary effects that touch upon religion are not constitutionally fatal.
  • the conversation focuses strictly on the science, the implications are still there.
  • one can legally justify teaching evolution while being sensitive to the fact that it has larger implications that touch upon the religious beliefs of many Americans.
  • evolutionary biology is based upon science, when we teach it as a science, the primary effect is to advance scientific knowledge.
  • a scientific theory like evolution does speak to ultimate questions about origins, which are also addressed by religion
  • it certainly touches upon religious questions. But when we discuss Darwinian evolution strictly on a scientific level, any effects upon religion are "secondary" or "incidental" compared to their primary effect of advancing scientific knowledge.
  • if creation science were a scientific theory, it could have been taught because any its touching upon religion would have been a secondary effect
  • approach was also followed in Crowley v. Smithsonian Institution, where a federal judge rejected arguments that Smithsonian exhibits on evolution established "secular humanism" because the "impact [on religion] is at most incidental to the primary effect of presenting a body of scientific knowledge"
  • Because evolution is based upon science, any effects upon religion would not bar its teaching.
  • [I]f a theory has scientific value and evidence to support it, its primary effect would be to advance knowledge of the natural world, not to advance religion
  • ultimate goal of schools is to educate students. Where a theory has scientific value and supporting evidence, it provides a basis for knowledge. Whether it coincidentally advances religion should not matter.
  • if government aid "is allocated on the basis of neutral, secular criteria that neither favor nor disfavor religion, and is made available to both religious and secular beneficiaries on a nondiscriminatory basis," then any effects upon religion are merely incidental.
  • best of both worlds. It allows science to be taught in the science classroom while respecting the beliefs of people who have religious objections to evolution.
Emily Freilich

What Is Education For? - 2 views

www.context.org/orr

education

shared by Emily Freilich on 22 Dec 13 - No Cached
  • The truth is that many things on which your future health and prosperity depend are in dire jeopardy: climate stability, the resilience and productivity of natural systems, the beauty of the natural world, and biological diversity.
  • this is not the work of ignorant people. It is, rather, largely the result of work by people with BAs, BSs, LLBs, MBAs, and PhDs.
  • Ignorance is not a solvable problem, but rather an inescapable part of the human condition. The advance of knowledge always carries with it the advance of some form of ignorance.
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  • What was wrong with their education? In Wiesel’s words: "It emphasized theories instead of values, concepts rather than human beings, abstraction rather than consciousness, answers instead of questions, ideology and efficiency rather than conscience."
  • In the modern curriculum we have fragmented the world into bits and pieces called disciplines and subdisciplines. As a result, after 12 or 16 or 20 years of education, most students graduate without any broad integrated sense of the unity of things. The consequences for their personhood and for the planet are large. For example, we routinely produce economists who lack the most rudimentary knowledge of ecology. This explains why our national accounting systems do not subtract the costs of biotic impoverishment, soil erosion, poisons in the air or water, and resource depletion from gross national product. We add the price of the sale of a bushel of wheat to GNP while forgetting to subtract the three bushels of topsoil lost in its production.
  • There is an information explosion going on, by which I mean a rapid increase of data, words, and paper. But this explosion should not be taken for an increase in knowledge and wisdom, which cannot so easily by measured. What can be said truthfully is that some knowledge is increasing while other kinds of knowledge are being lost. David Ehrenfeld has pointed out that biology departments no longer hire faculty in such areas as systematics, taxonomy, or ornithology. In other words, important knowledge is being lost because of the recent overemphasis on molecular biology and genetic engineering, which are more lucrative, but not more important, areas of inquiry.
  • The plain fact is that the planet does not need more "successful" people. But it does desperately need more peacemakers, healers, restorers, storytellers, and lovers of every shape and form. It needs people who live well in their places.
  • The goal of education is not mastery of subject matter, but of one’s person. Subject matter is simply the tool. Much as one would use a hammer and chisel to carve a block of marble, one uses ideas and knowledge to forge one’s own personhood.
  • knowledge carries with it the responsibility to see that it is well used in the world.
  • we cannot say that we know something until we understand the effects of this knowledge on real people and their communities
  • Indoor classes create the illusion that learning only occurs inside four walls isolated from what students call without apparent irony the "real world."
dpittenger

We're Underestimating the Risk of Human Extinction - The Atlantic - 0 views

www.theatlantic.com/...253821

extinction knowledge technology

shared by dpittenger on 09 Mar 15 - No Cached
  • we humans will destroy ourselves.
  • I think the biggest existential risks relate to certain future technological capabilities that we might develop, perhaps later this century. For example, machine intelligence or advanced molecular nanotechnology could lead to the development of certain kinds of weapons systems. You could also have risks associated with certain advancements in synthetic biology.
  • all observations require the existence of an observer. This becomes important, for instance, in evolutionary biology
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  • It's hard to know what that might look like, because our human experience might be just a small little crumb of what's possible. If you think of all the different modes of being, different kinds of feeling and experiencing, different ways of thinking and relating, it might be that human nature constrains us to a very narrow little corner of the space of possible modes of being. I
Javier E

Toddlers Have Sense of Justice, Puppet Study Shows - The New York Times - 0 views

www.nytimes.com/...ustice-puppet-study-shows.html

morality infant childhood development justice

shared by Javier E on 22 Jun 15 - No Cached
  • Children as young as age 3 will intervene on behalf of a victim, reacting as if victimized themselves, scientists have found.
  • In one experiment, when one puppet took toys or cookies from another puppet, children responded by pulling a string that locked the objects in an inaccessible cave. When puppets took objects directly from the children themselves, they responded in the same way.“The children treated these two violations equally,”
  • “Their sense of justice is victim-focused rather than perpetrator focused,” Dr. Jensen said. “The take-home message is that preschool children are sensitive to harm to others, and given a choice would rather restore things to help the victim than punish the perpetrator.”
Javier E

Book Review - The Information - By James Gleick - NYTimes.com - 0 views

www.nytimes.com/...formation-by-james-gleick.html

information theory science principles consciousness biology physics

shared by Javier E on 21 Mar 11 - No Cached
  • Information, he argues, is more than just the contents of our overflowing libraries and Web servers. It is “the blood and the fuel, the vital principle” of the world. Human consciousness, society, life on earth, the cosmos — it’s bits all the way down.
  • Shannon’s paper, published the same year as the invention of the transistor, instantaneously created the field of information theory, with broad applications in engineering and computer science.
  • information theory wound up reshaping fields from economics to philosophy, and heralded a dramatic rethinking of biology and physics.
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  • molecular biologists were soon speaking of information, not to mention codes, libraries, alphabets and transcription, without any sense of metaphor. In Gleick’s words, “Genes themselves are made of bits.” At the same time, physicists exploring what Einstein had called the “spooky” paradoxes of quantum mechanics began to see information as the substance from which everything else in the universe derives. As the physicist John Archibald Wheeler put it in a paper title, “It From Bit.”
Javier E

E. O. Wilson's Theory of Everything - Magazine - The Atlantic - 0 views

www.theatlantic.com/...3

theory wilson biology human society eusocial complexity

shared by Javier E on 15 Oct 11 - No Cached
  • Wilson told me the new proposed evolutionary model pulls the field “out of the fever swamp of kin selection,” and he confidently predicted a coming paradigm shift that would promote genetic research to identify the “trigger” genes that have enabled a tiny number of cases, such as the ant family, to achieve complex forms of cooperation.
  • In the book, he proposes a theory to answer what he calls “the great unsolved problem of biology,” namely how roughly two dozen known examples in the history of life—humans, wasps, termites, platypodid ambrosia beetles, bathyergid mole rats, gall-making aphids, one type of snapping shrimp, and others—made the breakthrough to life in highly social, complex societies. Eusocial species, Wilson noted, are by far “the most successful species in the history of life.”
  • Summarizing parts of it for me, Wilson was particularly unsparing of organized religion, likening the Book of Revelation, for example, to the ranting of “a paranoid schizophrenic who was allowed to write down everything that came to him.” Toward philosophy, he was only slightly kinder. Generation after generation of students have suffered trying to “puzzle out” what great thinkers like Socrates, Plato, and Descartes had to say on the great questions of man’s nature, Wilson said, but this was of little use, because philosophy has been based on “failed models of the brain.”
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  • His theory draws upon many of the most prominent views of how humans emerged. These range from our evolution of the ability to run long distances to our development of the earliest weapons, which involved the improvement of hand-eye coordination. Dramatic climate change in Africa over the course of a few tens of thousands of years also may have forced Australopithecus and Homo to adapt rapidly. And over roughly the same span, humans became cooperative hunters and serious meat eaters, vastly enriching our diet and favoring the development of more-robust brains. By themselves, Wilson says, none of these theories is satisfying. Taken together, though, all of these factors pushed our immediate prehuman ancestors toward what he called a huge pre-adaptive step: the formation of the earliest communities around fixed camps.
  • “When humans started having a camp—and we know that Homo erectus had campsites—then we know they were heading somewhere,” he told me. “They were a group progressively provisioned, sending out some individuals to hunt and some individuals to stay back and guard the valuable campsite. They were no longer just wandering through territory, emitting calls. They were on long-term campsites, maybe changing from time to time, but they had come together. They began to read intentions in each other’s behavior, what each other are doing. They started to learn social connections more solidly.”
  • “The humans become consistent with all the others,” he said, and the evolutionary steps were likely similar—beginning with the formation of groups within a freely mixing population, followed by the accumulation of pre-adaptations that make eusociality more likely, such as the invention of campsites. Finally comes the rise to prevalence of eusocial alleles—one of two or more alternative forms of a gene that arise by mutation, and are found at the same place on a chromosome—which promote novel behaviors (like communal child care) or suppress old, asocial traits. Now it is up to geneticists, he adds, to “determine how many genes are involved in crossing the eusociality threshold, and to go find those genes.”
  • Wilson posits that two rival forces drive human behavior: group selection and what he calls “individual selection”—competition at the level of the individual to pass along one’s genes—with both operating simultaneously. “Group selection,” he said, “brings about virtue, and—this is an oversimplification, but—individual selection, which is competing with it, creates sin. That, in a nutshell, is an explanation of the human condition.
  • “Within groups, the selfish are more likely to succeed,” Wilson told me in a telephone conversation. “But in competition between groups, groups of altruists are more likely to succeed. In addition, it is clear that groups of humans proselytize other groups and accept them as allies, and that that tendency is much favored by group selection.” Taking in newcomers and forming alliances had become a fundamental human trait, he added, because “it is a good way to win.”
  • If Wilson is right, the human impulse toward racism and tribalism could come to be seen as a reflection of our genetic nature as much as anything else—but so could the human capacity for altruism, and for coalition- and alliance-building. These latter possibilities may help explain Wilson’s abiding optimism—about the environment and many other matters. If these traits are indeed deeply written into our genetic codes, we might hope that we can find ways to emphasize and reinforce them, to build problem-solving coalitions that can endure, and to identify with progressively larger and more-inclusive groups over time.
carolinewren

Book Review: 'A New History of Life' by Peter Ward and Joe Kirschvink - WSJ - 0 views

www.wsj.com/...-and-joe-kirschvink-1425677187

biology Evolution

shared by carolinewren on 09 Mar 15 - No Cached
  • I imagine that physicists are similarly deluged with revelations about how to build a perpetual-motion machine or about the hitherto secret truth behind relativity. And so I didn’t view the arrival of “A New History of Life” with great enthusiasm.
  • subtitle breathlessly promises “radical new discoveries about the origins and evolution of life on earth,” while the jacket copy avers that “our current paradigm for understanding the history of life on Earth dates back to Charles Darwin’s time, yet scientific advances of the last few decades have radically reshaped that aging picture.”
  • authors Peter Ward and Joe Kirschvink are genuine scientists—paleontologists, to be exact. And they can write.
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  • even genuine scientists are human and as such susceptible to the allure of offering up new paradigms (as the historian of science Thomas Kuhn put it)
  • paleontologist Stephen Jay Gould insisted that his conception of “punctuated equilibria” (a kind of Marxist biology that blurred the lines between evolution and revolution), which he developed along with fellow paleontologist Niles Eldredge, upended the traditional Darwinian understanding of how natural selection works.
  • This notion doesn’t constitute a fundamental departure from plain old evolution by natural selection; it simply italicizes that sometimes the process is comparatively rapid, other times slower.
  • In addition, they have long had a peculiar perspective on evolution, because of the limitations of the fossil record
  • Darwin was a pioneering geologist as well as the greatest of all biologists, and his insights were backgrounded by the key concept of uniformitarianism, as advocated by Charles Lyell, his friend and mentor
  • previously regnant paradigm among geologists had been “catastrophism
  • fossil record was therefore seen as reflecting the creation and extinction of new species by an array of dramatic and “unnatural” dei ex machina.
  • Of late, however, uniformitarianism has been on a losing streak. Catastrophism is back, with a bang . . . or a flood, or a burst of extraterrestrial radiation, or an onslaught of unpleasant, previously submerged chemicals
  • This emphasis on catastrophes is the first of a triad of novelties on which “A New History of Life” is based. The second involves an enhanced role for some common but insufficiently appreciated inorganic molecules, notably carbon dioxide, oxygen and hydrogen sulfide.
  • Life didn’t so much unfold smoothly over hundreds of millions of years as lurch chaotically in response to diverse crises and opportunities: too much oxygen, too little carbon dioxide, too little oxygen, too much carbon dioxide, too hot, too cold
  • So far, so good, except that in their eagerness to emphasize what is new and different, the authors teeter on the verge of the same trap as Gould: exaggerating the novelty of their own ideas.
  • Things begin to unravel when it comes to the third leg of Messrs. Ward and Kirschvink’s purported paradigmatic novelty: a supposed role for ecosystems—rain forests, deserts, rivers, coral reefs, deep-sea vents—as units of evolutionary change
  • “While the history of life may be populated by species,” they write, “it has been the evolution of ecosystems that has been the most influential factor in arriving at the modern-day assemblage of life. . . . [W]e know that on occasion in the deep past entirely new ecosystems appear, populated by new kinds of life.” True enough, but it is those “new kinds of life,” not whole ecosystems, upon which natural selection acts.
  • One of the most common popular misconceptions about evolution is that it proceeds “for the good of the species.”
  • The problem is that smaller, nimbler units are far more likely to reproduce differentially than are larger, clumsier, more heterogeneous ones. Insofar as ecosystems are consequential for evolution—and doubtless they are—it is because, like occasional catastrophes, they provide the immediate environment within which something not-so-new is acted out.
  • This is natural selection doing its same-old, same-old thing: acting by a statistically potent process of variation combined with selective retention and differential reproduction, a process that necessarily operates within the particular ecosystem that a given lineage occupies.
Javier E

The Trouble With Brain Science - NYTimes.com - 0 views

www.nytimes.com/...rouble-with-brain-science.html

brain science theory science

shared by Javier E on 14 Jul 14 - No Cached
  • What would a good theory of the brain actually look like?
  • Different kinds of sciences call for different kinds of theories. Physicists, for example, are searching for a “grand unified theory” that integrates gravity, electromagnetism and the strong and weak nuclear forces into a neat package of equations.
  • The living world is bursting with variety and unpredictable complexity, because biology is the product of historical accidents, with species solving problems based on happenstance that leads them down one evolutionary road rather than another.
  • ...4 more annotations...
  • ut biological complexity is only part of the challenge in figuring out what kind of theory of the brain we’re seeking.
  • What we are really looking for is a bridge, some way of connecting two separate scientific languages — those of neuroscience and psychology.
  • An example is the discovery of DNA, which allowed us to understand how genetic information could be represented and replicated in a physical structure. In one stroke, this bridge transformed biology from a mystery — in which the physical basis of life was almost entirely unknown — into a tractable if challenging set of problems
  • We know that there must be some lawful relation between assemblies of neurons and the elements of thought, but we are currently at a loss to describe those laws.
dpittenger

3-D-printed organs are on the way - Nov. 4, 2014 - 0 views

money.cnn.com/...3d-printed-organs

science research technology

shared by dpittenger on 15 Jan 15 - No Cached
  • Add one more to the growing list of 3-D-printed products: human organs.
  • Within the next few years, Renard says 3-D-printed tissues could also be used in patient treatment, to replace small parts or organs or encourage cell regeneration.
  • Once the cells have been printed in the right arrangement, they begin to signal to one another, fuse and organize themselves into a collective system.
  • ...1 more annotation...
  • That hasn't stopped scientists from trying, however. Harvard researchers are at work trying to print functioning human kidneys, while a team at the University of Louisville is trying to produce a 3-D-printed heart.
  • dpittenger on 15 Jan 15
     
    Scientists are creating organs using 3d printers. This is a big scientific breakthrough and changes how we think about biology.
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