CHAPTER 3 – CANNIBALS | BRAINS | INTERNETS
For a general overview of Easter Island, see Inventing ‘Easter Island’ by Beverley Haun (Toronto: University of Toronto Press, 2008). For a detailed discussion of the overshoot of Easter Island, see Jared Diamond’s Collapse: How Societies Choose to Fail or Succeed (New York: Penguin, 2006).
For an interesting discussion about the brain’s energy consumption, see Nikhil Swaminathan’s article “Why Does the Brain Need So Much Power?,” Scientific American, April 29, 2008, which references this study: Fei Du, Xiao-Hong Zhu, Yi Zhang, Michael Friedman, Nanyin Zhang, Kâmil Uğurbil, and Wei Chen, “Tightly Coupled Brain Activity and Cerebral ATP Metabolic Rate,” Proceedings of the National Academy of Sciences 105, no. 17 (2008): 6409-6414.
The 20 percent number is widely recognized. See Marcus E. Raichle and Debra A. Gusnard, “Appraising the Brain’s Energy Budget,” Proceedings of the National Academy of Sciences 99, no. 16 (2002): 10237-10239.
There is no shortage of quality sources for the history of the internet, but a unique perspective worth reviewing comes from Internet Society. Also of note is Tubes: A Journey to the Center of the Internet (New York: Ecco, 2012), in which author Andrew Blum recounts his fascinating journey through the wires of the internet.
The “internet of things” has received much attention as of late. In addition to the aforementioned Cisco white paper and infographic, McKinsey & Company published a report in 2010 called “The Internet of Things.” The Economist published a special report in the November 4, 2010, issue called “Augmented Business” with the subheading “Smart Systems Will Disrupt Lots of Industries, and Perhaps the Entire Economy.”
For Metcalfe’s grave predictions about the internet, see “What’s Wrong with the Internet: It’s the Economy, Stupid,” IEEE Internet Computing, March/April 1997. Also of note is a speech Metcalfe gave in 2006 entitled “Framing the First Massachusetts Energy Summit.” Transcript reprinted online.
For a more in-depth look of the theory of how cooking drove our intelligence, see Richard Wrangham’s book Catching Fire: How Cooking Food Made Us Human (New York: Basic Books, 2009). Herculano-Houzel’s findings were published in the Proceedings of the National Academy of Sciences in 2012 in an article co-written with Karina Fonseca-Azevedo entitled “Metabolic Constraint Imposes Tradeoff between Body Size and Number of Brain Neurons in Human Evolution.” Herculano-Houzel, it should be noted, is the same person who discovered that we may have fewer than 100 billion neurons in our brain. Her findings came as a result of investigating the metabolic rates of consumption in the brain. For a brief overview of the findings of Richard Wrangham and Suzana Herculano-Houzel, see “Raw Food Not Enough to Feed Big Brains,” by Ann Gibbons in the October 22, 2012, edition of the journal Science Now.
The 2 percent consumption number comes from a report by Greenpeace released in 2011. They detailed the energy use of major internet companies and rated each on its level of environmental friendliness. The interactive report is available here.
Google was tight-lipped for years about its energy usage, but finally disclosed statistics in September 2011. The New York Times presented these stats in a September 8, 2011, article entitled “Google Details, and Defends, Its Use of Electricity” by James Glanz. Information about Google’s carrier hotel can be found in “Google to Buy New York Office Building,” Wall Street Journal, December 3, 2010.
George Miller’s article about the limits of short-term memory is well worth reading: “The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information,” Psychological Review 63, no.2 (1956): 81-97.
A brief overview of the growth of content-delivery networks and the scale at which they operate can be found in an article by Mari Sibley called “The Incredible Shrinking Internet,” which appeared in SmartPlanet on June 29, 2012.
Neuroscience has known about the fallibility of neurons for several decades, but the exact failure rate is unknown. The following two sources estimate that neurons fail to fire between 50 and 75 percent of the time: Alex M. Thomson, “Facilitation, Augmentation and Potentiation at Central Synapses,” Trends in Neurosciences 23, no. 7 (2000): 305–312; and William B. Levy and Robert A. Baxter, “Energy-Efficient Neuronal Computation via Quantal Synaptic Failures,” Journal of Neuroscience 22, no. 11 (2002): 4746–4755. A more recent figure was given in Discover magazine on November 6, 2009 in the article “Brain-Like Chip May Solve Computers’ Big Problem” by Douglas Fox. This article pegged the failure rate at 30 to 90 percent, an even bigger range (and higher maximum failure rate) than previously established.
The Neurogrid chip was featured in the aforementioned October 2009 Discover magazine article. The most recent scientific data were presented by Swadesh Choudhary, Steven Sloan, Sam Fok, Alexander Neckar, Eric Trautmann, Peiran Gao, Terry Stewart, Chris Eliasmith, and Kwabena Boahen, in their article “Silicon Neurons that Compute” presented at the International Conference on Artificial Neural Networks in 2012. Additional information on Stanford’s Neurogrid project can be found here.