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Erich Feldmeier

Strassmann & Queller: Close family ties keep cheaters in check: Why almost all multicel... - 0 views

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    ""Experiments with amoebae that usually live as individuals but must also join with others to form multicellular bodies to complete their life cycles showed that cooperation depends on kinship.

    If amoebae occur in well-mixed cosmopolitan groups, then cheaters will always be able to thrive by freeloading on their cooperative neighbors. But if groups derive from a single cell, cheaters will usually occur in all-cheater groups and will have no cooperators to exploit. A multicellular body like the human body is an incredibly cooperative thing," Queller says, "and sociobiologists have learned that really cooperative things are hard to evolve because of the potential for cheating.

    "It's the single-cell bottleneck that generates high relatedness among the cells that, in turn, allows them to cooperate, " he says."
Walid Damouny

World's oldest human remains claimed in Israel - 0 views

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    "Israeli archaeologists have discovered human remains dating from 400,000 years ago, challenging conventional wisdom that Homo sapiens originated in Africa, the leader of excavations in Israel said on Tuesday."
Walid Damouny

Acting selfish? Blame your mother - 0 views

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    (PhysOrg.com) -- The fact that our female ancestors dispersed more than our male ancestors can lead to conflicts within the brain that influence our social behaviour, new research reveals.
thinkahol *

Life in the Third Realm - Opinionator Blog - NYTimes.com - 0 views

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    It's that time of the month again. Yes: it's time for Life-form of the Month. In case you've forgotten, this coming Saturday is International Day for Biological Diversity, a day of celebrations and parties to appreciate the other occupants of the planet. So if you do nothing else this weekend, drink a toast to "Other Life-forms!" In honor of this event, my nomination for Life-form of the Month: May is a group of abundant and fascinating beings that are undeservedly obscure: the archaea.
Skeptical Debunker

Top home-school texts dismiss Darwin, evolution - Yahoo! News - 1 views

  • In this photo Friday, Feb. 26, 2010, Thirteen year-old Louisa Perry-Farr, left,
  • Christian-based materials dominate a growing home-school education market that encompasses more than 1.5 million students in the U.S. And for most home-school parents, a Bible-based version of the Earth's creation is exactly what they want. Federal statistics from 2007 show 83 percent of home-schooling parents want to give their children "religious or moral instruction."

    "The majority of home-schoolers self-identify as evangelical Christians," said Ian Slatter, a spokesman for the Home School Legal Defense Association. "Most home-schoolers will definitely have a sort of creationist component to their home-school program."

    Those who don't, however, often feel isolated and frustrated from trying to find a textbook that fits their beliefs.

    Two of the best-selling biology textbooks stack the deck against evolution, said some science educators who reviewed sections of the books at the request of The Associated Press.

    "I feel fairly strongly about this. These books are promulgating lies to kids," said Jerry Coyne, an ecology and evolution professor at the University of Chicago.

    The textbook publishers defend their books as well-rounded lessons on evolution and its shortcomings. One of the books doesn't attempt to mask disdain for Darwin and evolutionary science.

    "Those who do not believe that the Bible is the inspired, inerrant Word of God will find many points in this book puzzling," says the introduction to "Biology: Third Edition" from Bob Jones University Press. "This book was not written for them."

    The textbook delivers a religious ultimatum to young readers and parents, warning in its "History of Life" chapter that a "Christian worldview ... is the only correct view of reality; anyone who rejects it will not only fail to reach heaven but also fail to see the world as it truly is."

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    Home-school mom Susan Mule wishes she hadn't taken a friend's advice and tried a textbook from a popular Christian publisher for her 10-year-old's biology lessons.

    Mule's precocious daughter Elizabeth excels at science and has been studying tarantulas since she was 5. But she watched Elizabeth's excitement turn to confusion when they reached the evolution section of the book from Apologia Educational Ministries, which disputed Charles Darwin's theory.

    "I thought she was going to have a coronary," Mule said of her daughter, who is now 16 and taking college courses in Houston. "She's like, 'This is not true!'"
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    Home Fooling.
Skeptical Debunker

The genetic footprint of natural selection - 0 views

  • During evolution, living species have adapted to environmental constraints according to the mechanism of natural selection; when a mutation that aids the survival (and reproduction) of an individual appears in the genome, it then spreads throughout the rest of the species until, after several hundreds or even thousands of generations, it is carried by all individuals. But does this selection, which occurs on a specific gene in the genome of a species, also occur on the same gene in neighboring species? On which set of genes has natural selection acted specifically in each species?

    Researchers in the Dynamique et Organisation des Génomes team at the Institut de Biologie of the Ecole Normale Supérieure (CNRS/ENS/INSERM) have studied the genome of humans and three other primate species (chimpanzee, orangutan and macaque) using bioinformatics tools. Their work consisted in comparing the entire genomes of each species in order to identify the genes having undergone selection during the past 200,000 years. The result was that a few hundred genes have recently undergone selection in each of these species. These include around 100 genes detected in man that are shared by two or three other species, which is twice as many as might be anticipated as a random phenomenon. Thus a not inconsiderable proportion of the genes involved in human adaptation are also present in the chimpanzee, orangutan or macaque, and sometimes in several species at the same time. Natural selection acts not only by distancing different species from each other when new traits appear. But by acting on the same gene, it can also give rise to the same trait in species that have already diverged, but still have a relatively similar genome.

    This study thus provides a clearer understanding of the group of genes that are specifically implicated in human evolution (during the past 200,000 years), as it allows the identification of those genes which did not undergo selection in another primate line. An example that has been confirmed by this study is the well-known case of the lactase gene that can metabolize lactose during adulthood (a clear advantage with the development of agriculture and animal husbandry). The researchers have also identified a group of genes involved in some neurological functions and in the development of muscles and skeleton.

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    A further step has been taken towards our understanding of natural selection. CNRS scientists working at the Institut de Biologie of the Ecole Normale Supérieure (CNRS/ENS/INSERM) have shown that humans, and some of their primate cousins, have a common genetic footprint, i.e. a set of genes which natural selection has often tended to act upon during the past 200,000 years. This study has also been able to isolate a group of genes that distinguish us from our cousins the great apes. Its findings are published in PloS Genetics (26 February 2010 issue).
Walid Damouny

Glow-in-the-dark mushrooms discovered - LiveScience- msnbc.com - 2 views

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    "Freaky findings shed light on evolution of luminescence in nature"
Charles Daney

Ten things we don't understand about humans - New Scientist - 0 views

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    We belong to a remarkably quirky species. Despite our best efforts, some of our strangest foibles still defy explanation. But as science probes deeper into these eccentricities, it is becoming clear that behaviours and attributes that seem frivolous at first glance often go to the heart of what it means to be human.
Charles Daney

Study of huge numbers of genetic mutations point to oxidative stress as under... - 0 views

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    A study that tracked genetic mutations through the human equivalent of about 5,000 years has demonstrated for the first time that oxidative DNA damage is a primary cause of the process of mutation - the fuel for evolution but also a leading cause of aging, cancer and other diseases.
Charles Daney

Early Life Didn’t Just Divide, It United | Wired Science | Wired.com - 0 views

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    A massive analysis of almost every bacterial genome sequenced to date suggests a new shape for the tree of life. digg_url
Walid Damouny

Professor hatches century-old eggs to study evolution - 0 views

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    Suspending a life in time is a theme that normally finds itself in the pages of science fiction, but now such ideas have become a reality in the annals of science.
Walid Damouny

54-million-year-old skull reveals early evolution of primate brains - 0 views

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    Researchers at the University of Florida and the University of Winnipeg have developed the first detailed images of a primitive primate brain, unexpectedly revealing that cousins of our earliest ancestors relied on smell more than sight.
evo ata

Future Human Evolution - 0 views

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    Scientific and speculative articles about the future of human evolution regarding to artificial intelligence, genetic engineering, transhumanism, nanotechnology, space colonization, time travel, life extension and human enhancement
Barry mahfood

SINGULARITY & THE PRICE OF RICE - Singularity in Bite-Sized Bits: Accelerated Evolution... - 0 views

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    Researchers at Biodesign Institute have revved the engine of biological
    evolution to unheard of speed, creating completely new proteins in an
    infinitesimal fraction of the time it took nature to do the same thing.
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