Saturday, November 19, 2016

Good News For North Dakota; Quiet Tornado Season, But Winter Blasts Begin -- November 19, 2016

Freezing in north Texas, and it's not even winter yet! Getting reading to head out for a soccer tournament:

Do you remember the Kennedy clan worried that their children would never see snow again? LOL. I had completely forgotten that I even had a tag for that story: Never_See_Snow_Again. For the record, and for the Kennedy great grandchildren, at the moment:
  • Akeley, MN: 12 - 13 inches of snow
  • Leader, MN: 20 inches of snow
First 2016 - 2017 winter blast: all predicted by Farmers Almanac this year.

Telstar, The Tornadoes

Back To The Bakken

President Obama put more restrictions on US drilling in the Arctic.
Friday’s announcement fell short of fulfilling environmentalists’ pleas for more enduring protections that would keep U.S. Arctic, Atlantic and Pacific waters permanently off limits, though President Barack Obama could issue such a declaration any time before leaving office on January 20, 2017.
President-elect Donald Trump’s administration can rip up the five-year plan, but substantially replacing it and putting the Atlantic and Arctic back on the auction block would take years because of legally required public comment periods and environmental reviews.
The Bakken is going to be around for 50 years, probably more. The US will simply cede the Arctic to foreign countries.

Also, a new study on sources of high methane emissions is great news for the Bakken, but could become a headache for Ohio, Pennsylvania, and California.

Off The Net For Awhile -- Time For Waffles

Breakfast Reading

From the November 24, 2016, issue of The New York Review of Books:
This was one of the better issues.

For those interested in "the human brain," the Herclano-Houzel book is huge. HH was the first person to actually count accurately the number of neurons in the human brain. It is quite a story. But that is just the beginning.

Herclano-Houzel's resume
  • Federal University in Rio de Janeiro, undergraduate, virology
  • Case Western Reserve, Cleveland, OH, graduate studies in the nervous system
  • Max Planck Institute for Brain Research, Frankfurt, Germany, PhD in visual neurophysiology
  • Federal University in Rio, assistant professor
Upon returning to the University at Rio, she asked her colleagues, a rather simple question: how many neurons are there in the human brain? The number she was told was 100 billion. She asked for the source for that number. There was no source for that number. No one had actually counted the number of neurons in the human brain. It was simply an estimate based on an outmoded, inexact method of estimating the number of neurons in the human brain.

HH then proceeded to figure out how to do accurately count the number of neurons in the human brain. Precisely. The answer: brain soup.

That was the tool she needed to answer the question: what was the human advantage? How did the human brain become remarkable?

The answer: cooked food.

Along the way, some data points:
  • the human cerebral cortex constitutes 82% of total brain mass, the largest percentage when compared to all mammals, but the human cerebral cortex was found to contain only 19% of the total number of neurons in the brain
  • the percentage of neurons in the human cerebral cortex is the very same as that of the guinea pig and capybara, and miway in the 15 - 25% range found in most mammals
The question arises: how can the human cerebral cortex have expanded so greatly in comparison to the rest of the brain while maintaining a proportion of neurons equivalent to that found in small-brained animals, particularly primates? HH's answer with two hypotheses:
  • it has to do with the absolute number of neurons in the human cerebral cortex; and, 
  • partly in the fact that different scaling rules apply to the cerebral cortex and the cerebellum
  • the scaling rules are constant across all primates: when additional neurons are added to the brain, the cerebral cortex increases in mass at a much faster rate than does the cerebellum
  • this is because the cerebral cortex requires larger neurons than the cerebellum -- neurons that have long-range connections of several centimeters to link different cortical areas; neurons in the cerebellum need to span no more than a few millimeters
Through more discussion it boils down to this: the human advantage comes from no more than strength in numbers.

But what about the much bigger brains of elephants and whales? HH has not been able to get her hands on a cetacean brain, but with incredible difficulty, she did manage to get her hands on an elephant brain.
  • the elephant brain had more neurons than the human brain
  • not just a few more but three times as many: 247 billion to our 86 billion
  • but: 98% of these neurons were located in the cerebellum at the back of the brain
  • this left a mere 5.6 billion neurons in the 2.8-kg cerebral cortex of the elephant brain compared to 16 billion neurons in the human's 1.2-kg cerebral cortex (the human cerebral cortex is less than half the size of the elephant cerebral cortex, but has also almost three times the number of neurons
What are all those neurons doing in the elephant cerebellum? Most likely controlling its 100-kg and highly sensory muscular trunk.
As far as cooking food goes? Homo habilis reached its maximum brain size because its energy source was no different than the non-Homo primates, and there were not enough hours in the day to consume enough calories through foraging.

"Further expansion of the brain required securing more energy from the same type and quantity of foodstuffs. As from 1.5 million years ago that is just what our ancestors achieved by cooking their food.

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