Explaining the punctuation of equilibrium

The April, 2010 edition of Discover Magazine profiles biologist Lynne Margulis, famous for her well accepted suggestion that eukaryotic bacteria did not evolve in linear fashion, solely as as a result of natural selection. Rather,

mitochondria and plastids--vital structures within animal and plant cells--evolved from bacteria hundreds of millions of years ago, after bacterial cells started to collect and interactive communities and live symbiotically with one another. The resulting mergers yielded the compound cells known as eukaryotes, which in turn gave rise to all the rest-the protoctists, fungi, plants and animals, including humans.
There was a shocking idea at the time (1967), but, as described in this article by Dick Teresi, the more recent ideas of Margulis are even more controversial. The Discover Magazine article documents her arguments that symbiosis is "the central force behind the evolution of new species." This position runs counter to the holding of modern conventional scientific wisdom, that new species arise through "gradual accumulation of random mutations, which are either favored or weeded out by natural selection." Margulis holds that random mutation and natural selection play a minor role and that the big leaps in the evolutionary record "result from mergers between different kinds of organisms, what she calls symbiogenesis." The Discover article takes the form of an interview, in which the dominant theme is that "natural selection eliminates and maybe maintains, but it doesn't create." Margulis argues that the laws of genetics "show stasis, not change." She was prompted by the fact that there is no record of major fossil change until 542 million years ago, yet all of a sudden we see the Cambrian explosion. Stephen Jay Gould coined this phrase, "punctuated equilibrium," "to describe a discontinuity in the appearance of new species." According to Margulis, her explanation of symbiogenesis explains these discontinuities and should thus be considered the primary mechanism for evolution. Margulis carefully distinguishes her approach from arguments based on "intelligent design." She holds that those who advocate for "intelligent design" have nothing meaningful to offer to the scientific conversation. [More . . . ]

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Twins appear to share thoughts through thalamic bridge

Two extraordinarily unusual five-year old twins share more than conjoined skulls.  They appear to share some of their thoughts.  Susan Dominus of the New York Time covers this emotionally and scientifically rich story well from many angles.

Their brain images reveal what looks like an attenuated line stretching between the two organs, a piece of anatomy their neurosurgeon, Douglas Cochrane of British Columbia Children’s Hospital, has called a thalamic bridge, because he believes it links the thalamus of one girl to the thalamus of her sister. The thalamus is a kind of switchboard, a two-lobed organ that filters most sensory input and has long been thought to be essential in the neural loops that create consciousness. Because the thalamus functions as a relay station, the girls’ doctors believe it is entirely possible that the sensory input that one girl receives could somehow cross that bridge into the brain of the other. One girl drinks, another girl feels it.

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Creating Doubt in Science

There is currently a strong suite of Discovery Institute bills running through state legislatures to allow "alternative theories" to be taught in science classes. See list here: Antievolution Legislation Scorecard. There is not a direct link back to the Discovery Institute, but it is their wording, seen before and passed in places like Texas and Louisiana and Tennessee. From a legal standpoint, the bills look harmless, closely resembling intellectual freedom policies. But the point is clearly to sow confusion about the difference between science and just making things up, especially in regard to evolution and climate science. Hemant Mehta suggests that it would only be fair to show this video in churches where the churches put their books into science classes.

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The Hellhound and HeLa: Recent American Historical Writing At Its Best

The last really good history I read was "Hellhound On His Trail, " which follows James Earl Ray's path from his childhood in Alton, Illinois through a violent intersection with the life of Dr. Martin Luther King, Jr., and continues to follow Ray's trajectory with his quizzical recantations of his "life's purpose." With the same cool hand, Sides sketches the strengths and inadequacies of Dr. King's inner circle and paints larger atmospheric strokes with newspaper headlines on the increasing violence in response to desegregation and the influence of war in Vietnam on national sentiment about federal involvement in heretofore state affairs. By themselves, vignettes about Ray's lackluster career as a petty criminal, his stunted attempts at artistic grandeur and addiction to prostitutes would simply depress the reader. Here, the intentional failures and manipulations of Hoover's FBI and first-hand accounts of Ray's behavior appear like birds descending on a tragic town, flickering across the broader canvas creating momentum and dread. Awful as the true subject of this thriller may be, I found myself disappointed to reach the end.

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Your body as an incorrigible servant

Mind over matter, right? When your body aches and begs to stop running, you tell it to keep moving. When your body wants to go to sleep, you exert the will to make it to stay awake, or you make its arms pour coffee into its mouth. We make our bodies drive our cars to work lest those utility bills don’t get paid and “We” will suffer the consequences. Nietzsche began Chapter V of the Gay Science with the following quote as an illustration of his own conception of fearlessness (attributed to Henri de la Tour d’Auvergne, Vicomte de Turenne (1611-75) a great French general):

Sometimes during a battle he could not help trembling. Then he talked to his body as one talks to a servant. He said to it: “You tremble, carcass; but if you knew where I am taking you right now, you would tremble a lot more.”
“We” are in charge, right? Except when we are not. I can think of no better example than when we are nauseated, and our body dramatically takes over, the reverse peristalsis hurling out the offending food, dominating even our minds, until it’s over. Only then can “we” take over again. Consider food traveling in the other direction, too. So many of us tell our bodies to stop eating, yet our bodies keep eating. Day after day. We remind it to look in the mirror and we tell it about our tighter-fitting clothes, yet our bodies don’t care.

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