Our brain throws a lot of information away as it receives far more it can hold onto. It also has to make a trade off between speed and accuracy - a fast but inaccurate answer or a slow but more accurate one.
Most of the time, it opts for speed - interpreting events based on its rules of thumb, which might not always be logical. Psychologist Daniel Kahneman won the Nobel Prize for studying these rules of thumb and how they influence real-life behavior. Logical thinking, on the other hand, requires a lot of effort.
The problem of throwing away information, taking mental shortcuts, and inventing plausible stories is termed "change blindness". Our memory of the past is unreliable and our perception of the present is highly selective. Even when you imagine your future, your brain fills in many details, which may be unrealistic, and leaves out many others, which may be important.
Our brain selectively processes details that have historically been most relevant to survival - paying particular attention to events that are unexpected. It rarely tells us the truth, but most of the time it tells us what we need to know anyway!
P.S: The 10% Myth - You use your whole brain every day!
Welcome to Your Brain: Why You Lose Your Car Keys but Never Forget How to Drive and Other Puzzles of Everyday Life By Sandra Aamodt, Sam Wang
Saturday, May 10, 2008
Tuesday, May 6, 2008
Welcome to Your Brain - Introduction - Your Brain: A User's Guide
...the amazing three pounds in your skull...
You don't really use only 10 percent of your brain!
Welcome to Your Brain: Why You Lose Your Car Keys but Never Forget How to Drive and Other Puzzles of Everyday Life By Sandra Aamodt, Sam Wang
You don't really use only 10 percent of your brain!
Welcome to Your Brain: Why You Lose Your Car Keys but Never Forget How to Drive and Other Puzzles of Everyday Life By Sandra Aamodt, Sam Wang
The Big Switch - Epilogue - Flame and Filament
The wick was one of man's greatest, and also one of the most modest, inventions.
It tamed fire, "the soul of the house", and remained the dominant lighting technology all the way to the nineteenth century. We are still attracted to a flame at the end of a wick but we can no longer know what it was like when fire was the source of all light.
All technological change is generational change. As the older generations die, they take with them their knowledge of what was lost when the new technology arrived, and only the sense of what was gained remains. It's in this way that progress covers its tracks, perpetually refreshing the illusion that where we are is where we were meant to be.
The Big Switch: Our New Digital Destiny By Nicholas Carr
It tamed fire, "the soul of the house", and remained the dominant lighting technology all the way to the nineteenth century. We are still attracted to a flame at the end of a wick but we can no longer know what it was like when fire was the source of all light.
All technological change is generational change. As the older generations die, they take with them their knowledge of what was lost when the new technology arrived, and only the sense of what was gained remains. It's in this way that progress covers its tracks, perpetually refreshing the illusion that where we are is where we were meant to be.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Monday, May 5, 2008
The Big Switch - Chapter Eleven - iGod
In the foreseeable future, the human body may become augmented by digital processors and software. We might become programmable, too!
Without going to such extremes, technologies like Amazon's Mechanical Turk allow programs to ask people to perform minor tasks, which are trivial for humans (like recognizing a face) but hard for computers to do currently. We play a similar role in the operation of Google's search engine, without even realizing it! When you link to another document in your web page, you are expressing a judgment. Every time we create a link, we feed a little of our intelligence to Google which works by analyzing this "database of intentions".
We are the web's synapses. The more links we click and more pages we view - the faster we fire - the more intelligence the web collects and the more economic value it gains.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Without going to such extremes, technologies like Amazon's Mechanical Turk allow programs to ask people to perform minor tasks, which are trivial for humans (like recognizing a face) but hard for computers to do currently. We play a similar role in the operation of Google's search engine, without even realizing it! When you link to another document in your web page, you are expressing a judgment. Every time we create a link, we feed a little of our intelligence to Google which works by analyzing this "database of intentions".
We are the web's synapses. The more links we click and more pages we view - the faster we fire - the more intelligence the web collects and the more economic value it gains.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Sunday, May 4, 2008
The Big Switch - Chapter Ten - A Spider's Web
The arrival of the PC has been associated with a lack of control. However, any such breakdown of control proved fleeting. It's becoming increasingly easier to track stuff back to people on the internet. The connection of untethered computers into a network governed by strict protocols has actually created "a new apparatus of control". We accept this greater control in return for greater convenience.
The Big Switch: Our New Digital Destiny By Nicholas Carr
The Big Switch: Our New Digital Destiny By Nicholas Carr
Saturday, May 3, 2008
The Big Switch - Chapter Nine - Fighting the Net
By the end of 2006, 94% of email was spam, driven by extensive botnets. Beyond their moneymaking potential botnets can be used to sow destruction on the Internet itself. As the internet becomes more and more important as a shared global infrastructure, decisions about its governance will take on more weight.
The Big Switch: Our New Digital Destiny By Nicholas Carr
The Big Switch: Our New Digital Destiny By Nicholas Carr
Friday, May 2, 2008
The Big Switch - Chapter Eight - The Great unbundling
After peaking in 1984 with 64 million copies, the daily circulation of American news papers fell steadily, reaching 55 million in 2004. Newspapers try to bundle a lot of information together. When a newspaper moves online, the bundle falls apart. People go directly to the story that interests them, often ignoring everything else.
With the advent of context-based ads, the most successful article is the one which not only draws a lot of readers but also attracts high-priced ads. Unbundling is not unique to newspapers, it's the common feature of most online media. iTunes has unbundled music, services like TiVo are unbundling television, sites like YouTube unbundle video. Amazon and Google book search are unbundling even books, showing articles and snippets.
However, too much transparent personalization might lead to segregation since deliberations among like-minded people leads to "ideological amplification". The economist Thomas Schelling, who won the Nobel Prize eventually for his insight, explained how "small incentives, almost imperceptible differentials, can lead to strikingly polarized results". The view that the web will lead to a greater harmony must be examined with skepticism. Cultural impoverishment and social fragmentation seem equally likely outcomes.
The Big Switch: Our New Digital Destiny By Nicholas Carr
With the advent of context-based ads, the most successful article is the one which not only draws a lot of readers but also attracts high-priced ads. Unbundling is not unique to newspapers, it's the common feature of most online media. iTunes has unbundled music, services like TiVo are unbundling television, sites like YouTube unbundle video. Amazon and Google book search are unbundling even books, showing articles and snippets.
However, too much transparent personalization might lead to segregation since deliberations among like-minded people leads to "ideological amplification". The economist Thomas Schelling, who won the Nobel Prize eventually for his insight, explained how "small incentives, almost imperceptible differentials, can lead to strikingly polarized results". The view that the web will lead to a greater harmony must be examined with skepticism. Cultural impoverishment and social fragmentation seem equally likely outcomes.
The Big Switch: Our New Digital Destiny By Nicholas Carr
The Big Switch - Chapter Seven - From the Many to the Few
Youtube, Flickr, Skype and Craigslist are examples of companies that grew extremely fast with very few employees. Their businesses are constructed almost entirely out of software code. These companies also become more valuable (also to the users) as more and more people use them - a phenomenon called 'the network effect'. Such companies benefit from user-generated content - gifts of time and ideas by their huge number of users. Many of these sites were acquired by larger companies for millions, and even billions, of dollars.
The arrival of the universal computing grid might concentrate wealth in the hands of a small number of individuals, rather than a small number of companies. In the Youtube economy, everyone is free to play but only a few reap the rewards.
The Big Switch: Our New Digital Destiny By Nicholas Carr
The arrival of the universal computing grid might concentrate wealth in the hands of a small number of individuals, rather than a small number of companies. In the Youtube economy, everyone is free to play but only a few reap the rewards.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Wednesday, April 30, 2008
The Big Switch - Chapter Six - World Wide Computer
The Internet used to be an intellectual meeting-house before the Web transformed it into a commercial enterprise. By mid 1996, 70% of all domains were .com addresses, up from 5% in 1993.
Computing is similar to Electriciy in its transformational capability but is also different in many aspects - for example, there is no limit to how cheap services delivered online can get. Utilities to do almost everything - sending emails, instant messaging, internet telephony, finding directions, hosting photos and videos, publishing content - are available online for free.
Even companies can tap into this grid for standard services. In the long run, the IT department is unlikely to survive, at least not in its familiar form.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Computing is similar to Electriciy in its transformational capability but is also different in many aspects - for example, there is no limit to how cheap services delivered online can get. Utilities to do almost everything - sending emails, instant messaging, internet telephony, finding directions, hosting photos and videos, publishing content - are available online for free.
Even companies can tap into this grid for standard services. In the long run, the IT department is unlikely to survive, at least not in its familiar form.
The Big Switch: Our New Digital Destiny By Nicholas Carr
The Big Switch - Chapter Five - The White City
Inventions like the steam engine and electricity relegated more and more work to machines and reduced the need for talented craftsmen. They led to a 'deskilling' of the workplace. The newer white-collar office jobs increased the educational requirements of the workforce. The increase in wages created a vast American middle class which in return began to spend money on the latest electric appliances like the incandescent lamp, the electric fan, the electric iron, washing machines , vacuum cleaners and so on. Electricity also paved the way for the assembly line, allowing Ford to manufacture cheap cars.
The utility-supplied electricity was a major factor in shaping the American business and culture in the first half of the twentieth century.
The Big Switch: Our New Digital Destiny By Nicholas Carr
The utility-supplied electricity was a major factor in shaping the American business and culture in the first half of the twentieth century.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Tuesday, April 29, 2008
The Big Switch - Chapter Four - Goodbye Mr. Gates
Bill Gates sent a memo to Microsoft's staff on October 30, 2005 talking about how internet will unleash a "services wave" that "will be very disruptive". That was about the time when Google was constructing huge data centers - computing utilities that can be used to provide various services, like search, youtube, blogger, apps etc. Google is at the moment the biggest force in utility computing.
Other examples of this paradigm are Salesforce, S3 and EC2 by Amazon, and the various virtualization solutions.
The time of people who wrote code for the PC age is ending. The future of computing belongs to the new utilitarians.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Other examples of this paradigm are Salesforce, S3 and EC2 by Amazon, and the various virtualization solutions.
The time of people who wrote code for the PC age is ending. The future of computing belongs to the new utilitarians.
The Big Switch: Our New Digital Destiny By Nicholas Carr
The Big Switch - Chapter Three - Digital Millwork
Companies started using machines to process information as the twentieth century dawned. Computing became a general purpose technology. IT began to become an increasingly larger part of a company's expenditure. People who could operate them became a "priesthood of technicians".
Minicomputers arrived when Mainframes were dominating the market but didn't supplant them. They supplemented the bigger, more powerful machines and expanded the use of computers in businesses. It was the PC that upended the industry.
It democratized computing and made it more personal, but also made computing extremely inefficient. These single purpose systems resulted in very low levels of capital utilization. This is not just about computers being idle most of the time, it is also because of identical IT systems employed and maintained at almost every company. Companies like Microsoft, HP and Dell have fed over the complexity and inefficiency of this model.
Earlier attempts at providing computing as a utility had limited success because of insufficient network bandwidths. Now that the network barriers are collapsing, the PC age is giving way to the utility age.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Minicomputers arrived when Mainframes were dominating the market but didn't supplant them. They supplemented the bigger, more powerful machines and expanded the use of computers in businesses. It was the PC that upended the industry.
It democratized computing and made it more personal, but also made computing extremely inefficient. These single purpose systems resulted in very low levels of capital utilization. This is not just about computers being idle most of the time, it is also because of identical IT systems employed and maintained at almost every company. Companies like Microsoft, HP and Dell have fed over the complexity and inefficiency of this model.
Earlier attempts at providing computing as a utility had limited success because of insufficient network bandwidths. Now that the network barriers are collapsing, the PC age is giving way to the utility age.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Monday, April 28, 2008
The Big Switch - Chapter Two - The Inventor and his Clerk
Edison built a direct-current based distribution system for electricity and wanted to franchise it. His business empire (later consolidated into the Edison General Electric Company) supplied various critical components of this system - lamps, dynamos, wiring, etc. However, direct-current based systems were small, and could serve only the nearby offices and homes.
In contrast, the alternating current system, developed by the Serbian inventor Nikola Tesla, allowed the utility companies to transmit electriciy over great distances. Companies like those of Samuel Insull, who used to be the secretary of Edison, perfected the large scale utility model. Eventually, the age of the private power plant was over. The utility had triumphed.
The Big Switch: Our New Digital Destiny By Nicholas Carr
In contrast, the alternating current system, developed by the Serbian inventor Nikola Tesla, allowed the utility companies to transmit electriciy over great distances. Companies like those of Samuel Insull, who used to be the secretary of Edison, perfected the large scale utility model. Eventually, the age of the private power plant was over. The utility had triumphed.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Saturday, April 26, 2008
The Big Switch - Chapter One - Burden's Wheel
Industrial water-wheels, steam engines and electric generators became obsolete when utility companies started supplying electricity over the network. Manufacturers didn't want to be in the power-generation business, they just wanted to use it. Tapping into a centrally supplied utility became efficient and cheap. The same thing is happening to computing now. The grid wins.
Waterwheels and steam engines also supplied power but they lacked an important advantage. They cannot be supplied efficiently from a central location unlike electricity or computing and couldn't achieve the scale economies of central supply.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Waterwheels and steam engines also supplied power but they lacked an important advantage. They cannot be supplied efficiently from a central location unlike electricity or computing and couldn't achieve the scale economies of central supply.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Thursday, April 24, 2008
The Big Switch - Prologue: A Doorway in Boston
Corporate computer systems are not all that important to a company's success now. They are necessary, sure, but so commonplace that they no longer provide a company with an edge over its competition. Information technology has become just another cost of doing business.
Computing is becoming a utility, a cheap, universal commodity.
The Big Switch: Our New Digital Destiny By Nicholas Carr
Computing is becoming a utility, a cheap, universal commodity.
The Big Switch: Our New Digital Destiny By Nicholas Carr
The Quotable Einstein
Einstein's [violin] playing is excellent, but he does not deserve his world fame; there are many others just as good.
A Berlin music critic on an early 1920s performance, unaware that Einstein's fame derived from physics, not music; quoted in Reiser, Albert Einstein, pp. 202-203
The Quotable Einstein, compiled by Alice Calaprice
A Berlin music critic on an early 1920s performance, unaware that Einstein's fame derived from physics, not music; quoted in Reiser, Albert Einstein, pp. 202-203
The Quotable Einstein, compiled by Alice Calaprice
The Quotable Einstein
Einstein explained his theory to me every day, and soon I was fully convinced that he understood it.
Chaim Weizmann, 1929.
The Quotable Einstein, compiled by Alice Calaprice
Chaim Weizmann, 1929.
The Quotable Einstein, compiled by Alice Calaprice
The Quotable Einstein
One of the greatest - perhaps the greatest - of achievements in the history of human thought.
Joseph John Thomson, discoverer of the electron, referring to Einstein's work on general relativity, 1919, quoted in Hoffman, Albert Einstein: Creator and Rebel, p. 132
The Quotable Einstein, compiled by Alice Calaprice
Joseph John Thomson, discoverer of the electron, referring to Einstein's work on general relativity, 1919, quoted in Hoffman, Albert Einstein: Creator and Rebel, p. 132
The Quotable Einstein, compiled by Alice Calaprice
Wednesday, April 23, 2008
The Quotable Einstein
What Einstein said wasn't all that stupid.
Wolfgang Pauli as a student, after hearing Einstein, twenty years his senior, give a lecture; quoted in Ehlers, Liebes Hertz! p.47
The Quotable Einstein, compiled by Alice Calaprice
Wolfgang Pauli as a student, after hearing Einstein, twenty years his senior, give a lecture; quoted in Ehlers, Liebes Hertz! p.47
The Quotable Einstein, compiled by Alice Calaprice
The Quotable Einstein
Words or language, as they are written or spoken, do not seem to play any role in my mechanism of thought.
1945; from Appendix 2 in Hadamard, An Essay on the Psychology of Invention in the Mathematical Field
The Quotable Einstein, compiled by Alice Calaprice
1945; from Appendix 2 in Hadamard, An Essay on the Psychology of Invention in the Mathematical Field
The Quotable Einstein, compiled by Alice Calaprice
The Quotable Einstein
I was sitting in the patent office in Bern when all of a sudden a thought occurred to me: if a person falls freely, he won't feel his own weight. I was startled. This simple thought made a deep impression on me. It impelled me toward a theory of gravitation.
In Kyoto lecture, 1922; quoted in J. Ishiwara, Einstein Koen-Roku (Tokyo, 1977)
The Quotable Einstein, compiled by Alice Calaprice
In Kyoto lecture, 1922; quoted in J. Ishiwara, Einstein Koen-Roku (Tokyo, 1977)
The Quotable Einstein, compiled by Alice Calaprice
Tuesday, April 22, 2008
The Quotable Einstein
I do not consider myself the father of the release of atomic energy. My part in it was quite indirect. I did not, in fact, foresee that it would be released in my time. I believed only that it was theoretically possible. It became practical only through the accidental discovery of chain reaction, and this was not something I could have predicted.
From "Atomic War or Peace," Atlantic Monthly, November 1945
The Quotable Einstein, compiled by Alice Calaprice
From "Atomic War or Peace," Atlantic Monthly, November 1945
The Quotable Einstein, compiled by Alice Calaprice
The Quotable Einstein
I have done no work on [the atomic bomb], no work at all.
Quoted in the New York Times, August 12, 1945.
The Quotable Einstein, compiled by Alice Calaprice
Quoted in the New York Times, August 12, 1945.
The Quotable Einstein, compiled by Alice Calaprice
The Quotable Einstein
Some recent work by E. Fermi and L. Szilard, which has been communicated to me in manuscript, leads me to expect that the element uranium may be turned into a new and important source of energy in the immediate future. Certain aspects of the situation which has arisen seem to call for watchfulness and, if necessary, quick action on the part of the Administration.
From a letter to President Franklin D. Roosevelt, August 2, 1939, resulting in the appropriation of government funds for the development of the atomic bomb; the letter was composed by Leo Szilard and signed by Einstein; Einstein Archive 33-088; full text reprinted in Clark, Einstein, pp. 556-557
The Quotable Einstein, compiled by Alice Calaprice
From a letter to President Franklin D. Roosevelt, August 2, 1939, resulting in the appropriation of government funds for the development of the atomic bomb; the letter was composed by Leo Szilard and signed by Einstein; Einstein Archive 33-088; full text reprinted in Clark, Einstein, pp. 556-557
The Quotable Einstein, compiled by Alice Calaprice
The Quotable Einstein
I cannot understand the passive response of the whole civilized world to this modern barbarism. Doesn't the world see that Hitler is aiming for war?
October 1, 1933; quoted by a reporter for Bunte Welt (Vienna); quoted in Pais, Einstein Lived Here, p. 194
The Quotable Einstein, compiled by Alice Calaprice
October 1, 1933; quoted by a reporter for Bunte Welt (Vienna); quoted in Pais, Einstein Lived Here, p. 194
The Quotable Einstein, compiled by Alice Calaprice
Monday, April 21, 2008
The Quotable Einstein
He remains in many ways the foremost prophet of our time.... There is no one today with Tolstoi's deep insight and moral force.
From an interview, "Peace Must Be Waged," for Survey Graphic, August 1934; quoted in Nathan and Norden, Einstein on Peace, p. 261.
The Quotable Einstein, compiled by Alice Calaprice
From an interview, "Peace Must Be Waged," for Survey Graphic, August 1934; quoted in Nathan and Norden, Einstein on Peace, p. 261.
The Quotable Einstein, compiled by Alice Calaprice
The Quotable Einstein
A leader of his people, unsupported by any outward authority: a politician whose success rests not upon craft nor the mastery of technical devices, but simply on the convincing power of his personality; a victorious fighter who has always scorned the use of force; a man of wisdom and humility, armed with resolve and inflexible consistency, who has devoted all his strength to the uplifting of his people and the betterment of their lot; a man who has confronted the brutality of Europe with the dignity of the simple human being, and thus at all times risen superior.
Generations to come, it may be, will scarce believe that such a one as this ever in flesh and blood walked upon this earth.
Statement on occasion of Gandhi's seventieth birthday, 1939; unpublished elsewhere, quoted in Einstein on Humanism, p. 94
The Quotable Einstein, compiled by Alice Calaprice
Generations to come, it may be, will scarce believe that such a one as this ever in flesh and blood walked upon this earth.
Statement on occasion of Gandhi's seventieth birthday, 1939; unpublished elsewhere, quoted in Einstein on Humanism, p. 94
The Quotable Einstein, compiled by Alice Calaprice
The Quotable Einstein
Alas, you find [vanity] in so many scientists. It has always hurt me that Galileo did not acknowledge the work of Kepler.
To I. Bernard Cohen, April 1955; quoted in French, Einstein: A Centenary Volume, p. 41
The Quotable Einstein, compiled by Alice Calaprice
To I. Bernard Cohen, April 1955; quoted in French, Einstein: A Centenary Volume, p. 41
The Quotable Einstein, compiled by Alice Calaprice
Sunday, April 20, 2008
The Quotable Einstein
Madame Curie is intelligent but as cold as a herring, meaning that she is lacking in all feelings of joy and sorrow. Almost the only way in which she expresses her feelings is to rail at things she doesn't like. And she has a daughter who is even worse - like a grenadier. This daughter is also very gifted.
Letter to Elsa Lowenthal, August 11?, 1913; CPAE, Vol. 5, Doc. 465
The Quotable Einstein, compiled by Alice Calaprice
Letter to Elsa Lowenthal, August 11?, 1913; CPAE, Vol. 5, Doc. 465
The Quotable Einstein, compiled by Alice Calaprice
Wednesday, April 16, 2008
The Quotable Einstein
Yes, but where are its wheels?
Two-year-old Albert, after the birth of Maja in 1881, upon being told he would now have something to play with; in "Biographic Sketch" by Maja Winteler-Einstein, in CPAE, Vol. 1, p. lvii
The Quotable Einstein, compiled by Alice Calaprice
Two-year-old Albert, after the birth of Maja in 1881, upon being told he would now have something to play with; in "Biographic Sketch" by Maja Winteler-Einstein, in CPAE, Vol. 1, p. lvii
The Quotable Einstein, compiled by Alice Calaprice
Tuesday, April 15, 2008
The Quotable Einstein
All my life I have dealt with objective matters; hence I lack both the natural aptitude and the experience to deal properly with people and to exercise official functions.
Statement to Abba Eban, November 18, 1952, turning down the presidency of Israel after Chaim Weizmann's death; Einstein Archive 28-943.
The Quotable Einstein, compiled by Alice Calaprice
Statement to Abba Eban, November 18, 1952, turning down the presidency of Israel after Chaim Weizmann's death; Einstein Archive 28-943.
The Quotable Einstein, compiled by Alice Calaprice
The Quotable Einstein
I have to apologize to you that I am still among the living. There will be a remedy for this, however.
Letter to a child, Tyffany Williams, August 25, 1946, after she expressed surprise that Einstein was still alive, Einstein Archive 42-612.
The Quotable Einstein, compiled by Alice Calaprice
Letter to a child, Tyffany Williams, August 25, 1946, after she expressed surprise that Einstein was still alive, Einstein Archive 42-612.
The Quotable Einstein, compiled by Alice Calaprice
Monday, April 14, 2008
The Quotable Einstein
I have never looked upon ease and happiness as ends in themselves - such an ethical basis I call the ideal of a pigsty.... The ideals which have lighted my way, and time after time have given me new courage to face life cheerfully, have been Kindness, Beauty and Truth.
From "What I Believe", in Forum and Century 84(1930),
pp. 193-194; reprinted in Ideas and Opinions, pp. 8 -11
The Quotable Einstein, compiled by Alice Calaprice
From "What I Believe", in Forum and Century 84(1930),
pp. 193-194; reprinted in Ideas and Opinions, pp. 8 -11
The Quotable Einstein, compiled by Alice Calaprice
Sunday, April 13, 2008
Ever Since Darwin, Epilogue
Socio-biologists argue that all major human behavioral patterns must be adaptive as the products of natural selection. Extending this argument even further, are humans just instruments that genes use to make even more genes like themselves?
Molecular evolutionists argue that evolutionary change is not only uninfluenced by natural selection but is truly random in direction. For example, more than one DNA sequence yields the same amino acid. How can a genetic change from one redundant sequence to another be controlled by natural selection? (since selection will "see" the same amino acid in both cases)
In the end, Darwinian pluralism might triumph.
Selection will be important but not omnipotent.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Molecular evolutionists argue that evolutionary change is not only uninfluenced by natural selection but is truly random in direction. For example, more than one DNA sequence yields the same amino acid. How can a genetic change from one redundant sequence to another be controlled by natural selection? (since selection will "see" the same amino acid in both cases)
In the end, Darwinian pluralism might triumph.
Selection will be important but not omnipotent.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 8: The Science and Politics of Human Nature, 33: So Cleverly Kind an Animal
If individual advantage, as Darwin argues, is the only criterion of success in nature, how can we explain altruism in humans?
Theory of kin selection can help. It's the idea that animals evolve behaviors that endanger or sacrifice themselves only if such altruistic acts increase their own genetic potential by benefiting kin. If you are walking with three of your brothers and a situation arises in which you can save your brothers by giving up your life, what should you do? If your three brothers live, they'll propagate 150% of your genes while you have only 100% of yours!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Theory of kin selection can help. It's the idea that animals evolve behaviors that endanger or sacrifice themselves only if such altruistic acts increase their own genetic potential by benefiting kin. If you are walking with three of your brothers and a situation arises in which you can save your brothers by giving up your life, what should you do? If your three brothers live, they'll propagate 150% of your genes while you have only 100% of yours!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Saturday, April 12, 2008
Ever Since Darwin, 8: The Science and Politics of Human Nature, 32: Biological Potentiality vs Biological Determinism
Is there a genetic basis for the universal patterns in human behavior?
Or is nurture superior to nature?
The issue is not biology vs humans but biological determinism vs biological potentiality.
If genetic determinism is true, we'd have to live with it but no evidence exists yet to support it. It's continued popularity is due to the social prejudice of those who benefit from it.
Our biological nature does not stand in the way of our social reform.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Or is nurture superior to nature?
The issue is not biology vs humans but biological determinism vs biological potentiality.
If genetic determinism is true, we'd have to live with it but no evidence exists yet to support it. It's continued popularity is due to the social prejudice of those who benefit from it.
Our biological nature does not stand in the way of our social reform.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 8: The Science and Politics of Human Nature, 31: Racist Arguments and IQ
There are no unambiguous results tying racial divisions to intelligence. Biological determinism is interesting to a lot of people because it blames the victims and helps evade responsibility for the state of matters.
John Stuart Mill once wrote: "Of all the vulgar modes of escaping from the consideration of the effect of social and moral influences upon the human mind, the most vulgar is that of attributing the diversities of conduct and character to inherent natural differences"
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
John Stuart Mill once wrote: "Of all the vulgar modes of escaping from the consideration of the effect of social and moral influences upon the human mind, the most vulgar is that of attributing the diversities of conduct and character to inherent natural differences"
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
The Unfolding of Language: An evolutionary tour of mankind's greatest invention, 3: The Forces of Destruction, 75
So the English of today is not what it used to be, but then again, it never was.
The Unfolding of Language: An evolutionary tour of mankind's greatest invention, 2: Perpetual Motion, 71
The most important discovery we have made so far is that language is in a state of constant flux. While no one in particular seems to be going about changing it, a few deep-rooted motives that drive all of us (economy, expressiveness, analogy) create powerful forces of change and ensures that sounds, meanings and even structures are always on the move. And while our capacity to accommodate synchronic variation means that we are often hardly aware that one form is usurping another, changes can proceed so quickly that after just a few centuries a language can hardly recognize itself when leafing through the old family albums.
Thursday, April 10, 2008
Ever Since Darwin, 8: The Science and Politics of Human Nature, 30: The Nonscience of Human Nature
Biological determinism - the idea that our violence, aggressiveness and other unattractive traits are due to genes - has been getting some press lately. However, there is no single unambiguous fact supporting its claims.
Its proponents thoroughly underrate the influence of society and culture on human behavior. It's easy to fob off responsibility if everything is due to genes!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Its proponents thoroughly underrate the influence of society and culture on human behavior. It's easy to fob off responsibility if everything is due to genes!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 8: The Science and Politics of Human Nature, 29: Why We Should Not Name Races
Homo sapiens is a strongly differentiated species.
But variability does not warrant a designation of races.
There are better ways to study human differences.
How can we study geographic variability then?
Multivariate analysis offers an objective mapping based on a lot of characteristics while races are subjective. Almost all proponents of multivariate analysis decline to name subspecies. You cannot map a continuous distribution if each specimen has to be assigned to a discrete subdivision.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
But variability does not warrant a designation of races.
There are better ways to study human differences.
How can we study geographic variability then?
Multivariate analysis offers an objective mapping based on a lot of characteristics while races are subjective. Almost all proponents of multivariate analysis decline to name subspecies. You cannot map a continuous distribution if each specimen has to be assigned to a discrete subdivision.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 7: Science in Society - A Historical View, 28: The Criminal as Nature's Mistake
Biological theories of criminality aren't new.
There has been no real evidence to support such theories.
Why do we wish to fob off responsibility for our violence and sexism upon our genes?
The hallmark of humanity isn't just our mental capacity but also our mental flexibility.
We have made our world and we can change it.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
There has been no real evidence to support such theories.
Why do we wish to fob off responsibility for our violence and sexism upon our genes?
The hallmark of humanity isn't just our mental capacity but also our mental flexibility.
We have made our world and we can change it.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 7: Science in Society - A Historical View, 27: Racism and Recapitulation
When the theory of recapitulation (the idea that individuals repeat the adult stages of their ancestors during their embryonic and juvenile growth) was being proposed, blacks were deemed inferior by some scientists because they were supposedly retaining juvenile traits.
Eventually, when the theory of neoteny (the idea that humans retain the juvenile traits of their ancestors, not the adult characteristics) came into fashion, the same scientists started to look for evidence to prove how whites retain more juvenile traits than blacks.
Further, it's not hard to argue men are superior to women under the theory of capitulation. It becomes trickier with neoteny since women are more childlike in their anatomy!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Eventually, when the theory of neoteny (the idea that humans retain the juvenile traits of their ancestors, not the adult characteristics) came into fashion, the same scientists started to look for evidence to prove how whites retain more juvenile traits than blacks.
Further, it's not hard to argue men are superior to women under the theory of capitulation. It becomes trickier with neoteny since women are more childlike in their anatomy!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Monday, April 7, 2008
Ever Since Darwin, 7: Science in Society - A Historical View, 26: Posture Maketh the Man
We developed our upright posture before we developed our large brains. This freeing of hands for using tools might have contributed to the evolutionary enlargement of our brains.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 7: Science in Society - A Historical View, 25: On Heroes and Fools in Science
Science is not just successive accumulation of facts.
It is a creative activity, its geniuses acting more as artists than information processors.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
It is a creative activity, its geniuses acting more as artists than information processors.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Sunday, April 6, 2008
Ever Since Darwin, 6: Size and Shape, from churches to brains to planets, 24: Planetary Sizes and Surfaces
Earth's size is a major reason for its unique surface, compared to other bodies like the moon, Mercury or Mars. Earth's surface-volume ratio is small enough for its crust to break into plates and it is big enough to generate the level of internal heat required to move these plates around.
Moon and Mercury cannot generate the necessary internal heat to have an active surface. What about Mars? Mars' surface might represent an unsuccessful try at plate tectonics; its crust fractured but could not move.
Pascal once remarked, knowledge is like a sphere in space. the more we learn (volume of the sphere), the greater our contact with the unknown (surface of the sphere). True enough - but considering the surface-volume relationship - the larger the sphere, the greater the ratio of known (volume) to unknown (surface)!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Moon and Mercury cannot generate the necessary internal heat to have an active surface. What about Mars? Mars' surface might represent an unsuccessful try at plate tectonics; its crust fractured but could not move.
Pascal once remarked, knowledge is like a sphere in space. the more we learn (volume of the sphere), the greater our contact with the unknown (surface of the sphere). True enough - but considering the surface-volume relationship - the larger the sphere, the greater the ratio of known (volume) to unknown (surface)!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 6: Size and Shape, from churches to brains to planets, 23: History of the Vertebrate Brain
Animals making a living by catching rapidly moving prey seem to need bigger brains than plant eaters. As herbivores developed bigger brains (presumably under selective pressure by carnivores), carnivores evolved their own brains - a positive feedback loop - to maintain the differential.
What about us? Why are we so "brainy"?
The most ancient brain cast of a primate belongs to a 55-million-year-old creature named Tetonius Homunculus. Even that is three times larger than the expected brain size of an average mammal of its body weight. Primates have been ahead right from the start; our large brain is only an exaggeration of a pattern set at the beginning of the age of mammals (the last 70 million years)
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
What about us? Why are we so "brainy"?
The most ancient brain cast of a primate belongs to a 55-million-year-old creature named Tetonius Homunculus. Even that is three times larger than the expected brain size of an average mammal of its body weight. Primates have been ahead right from the start; our large brain is only an exaggeration of a pattern set at the beginning of the age of mammals (the last 70 million years)
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 6: Size and Shape, from churches to brains to planets, 22: Sizing up Human Intelligence
More than 99% of animal species are smaller than we are.
Even among the 190 species of primates, only the gorilla regularly exceeds us in size.
Our size has a lot to do with the development of our brain.
Nature doesn't miniaturize cells. Small animals have fewer neurons in their brains, not smaller ones. Our large size served as a prerequisite for our self-conscious intelligence.
Then, how come elephants and whales have still larger brains and not have superior mental ability? Larger bodies just need larger brains. In fact, smaller animals have more brain per unit body weight than larger animals. The right criterion isn't the ratio between brain-body weights (brain weight increases at about two-thirds the rate of the body if we plot these weights for several animals). It's the ratio between the actual brain weight and the expected brain weight at that body weight. By this measure, we are the brainiest animal by far.
Is this just due to an increase in the body size for our species? No, our brain weight has increased much more rapidly than any prediction based on body weight increases would allow. We are indeed smarter than we were!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Even among the 190 species of primates, only the gorilla regularly exceeds us in size.
Our size has a lot to do with the development of our brain.
Nature doesn't miniaturize cells. Small animals have fewer neurons in their brains, not smaller ones. Our large size served as a prerequisite for our self-conscious intelligence.
Then, how come elephants and whales have still larger brains and not have superior mental ability? Larger bodies just need larger brains. In fact, smaller animals have more brain per unit body weight than larger animals. The right criterion isn't the ratio between brain-body weights (brain weight increases at about two-thirds the rate of the body if we plot these weights for several animals). It's the ratio between the actual brain weight and the expected brain weight at that body weight. By this measure, we are the brainiest animal by far.
Is this just due to an increase in the body size for our species? No, our brain weight has increased much more rapidly than any prediction based on body weight increases would allow. We are indeed smarter than we were!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 6: Size and Shape, from churches to brains to planets, 21: Size and Shape
Who could believe an ant in theory?
A giraffe in blueprint?
Ten thousand doctors of what's possible
Could reason half the jungle out of being.
- John Ciardi
Volume grows more rapidly than surface.
One solution to decreasing surface: development of internal organs (lungs, intestinal villi)
For small creatures with high surface to volume ratios, gravity isn't an issue. Surface forces are far more influential.
Even with churches, small ones don't have and don't need transepts. As churches become larger, more surface is needed to allow more light inside. Animals invented internal organs to keep the same outward shape while volume increases. Architects can scale buildings in the same way because of inventions like internal lighting and structural steel.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
A giraffe in blueprint?
Ten thousand doctors of what's possible
Could reason half the jungle out of being.
- John Ciardi
Volume grows more rapidly than surface.
One solution to decreasing surface: development of internal organs (lungs, intestinal villi)
For small creatures with high surface to volume ratios, gravity isn't an issue. Surface forces are far more influential.
Even with churches, small ones don't have and don't need transepts. As churches become larger, more surface is needed to allow more light inside. Animals invented internal organs to keep the same outward shape while volume increases. Architects can scale buildings in the same way because of inventions like internal lighting and structural steel.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Saturday, April 5, 2008
Ever Since Darwin, 5: Theories of the Earth, 20: The Validation of Continental Drift
Alfred Wegener proposed the theory of continental drift but could offer no plausible mechanism by which it occurred. The proponents of the theory imagined that the continents plowed their way through the static ocean floor.
Paleontological evidence that supports continental drift was dismissed because such drift was "impossible".
However, under the theory of plate tectonics, continental drift is an inescapable consequence. The same paleontological evidence mentioned above is now cited as "proof" of continental drift!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Paleontological evidence that supports continental drift was dismissed because such drift was "impossible".
However, under the theory of plate tectonics, continental drift is an inescapable consequence. The same paleontological evidence mentioned above is now cited as "proof" of continental drift!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 5: Theories of the Earth, 19: Velikovsky in Collision
Velikovsky is one of the latest people to propose a theological theory of geology. His claims are mostly wrong but we should not ignore all nonprofessional scientific heresy.
Many great scientific advances were "nonprofessional scientific heresy" when they were proposed.
However, we should also remember that for each successful heretic, there are a hundred forgotten people who challenged the existing notions and lost.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Many great scientific advances were "nonprofessional scientific heresy" when they were proposed.
However, we should also remember that for each successful heretic, there are a hundred forgotten people who challenged the existing notions and lost.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 5: Theories of the Earth, 18: Uniformity and Catastrophe
In the early 19th century, geology was dominated by catastrophists who argued that cataclysmic events are needed to explain the features of the earth. They were mainly theological apologists who sought these events to make geological history conform to the Bible.
Charles Lyell proposed his revolutionary philosophy of "Uniformitarianism" in his "Principles of Geology" (1830). It advocated that a slow and steady operation of present causes (rivers, rain etc) over a really long period of time to bring about the earth we see now. The present is the key to the past. His opponents weren't really proposing supernatural reasons for catastrophes by 1830 but his theory still made the important contribution of the steady state idea.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Charles Lyell proposed his revolutionary philosophy of "Uniformitarianism" in his "Principles of Geology" (1830). It advocated that a slow and steady operation of present causes (rivers, rain etc) over a really long period of time to bring about the earth we see now. The present is the key to the past. His opponents weren't really proposing supernatural reasons for catastrophes by 1830 but his theory still made the important contribution of the steady state idea.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 5: Theories of the Earth, 17: Burnet's Dirty Little Planet
Older or theological theories of earth might seem fanciful or utterly fantastic to us.
Consider Burnet's theory of earth for example.
It was a fairly rationalist theory for 1681, even though it was based on the Bible.
It's not always religion that obstructs science.
Mostly it is dogmatists and antirationalists, rather than theists, that try to suppress science.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Consider Burnet's theory of earth for example.
It was a fairly rationalist theory for 1681, even though it was based on the Bible.
It's not always religion that obstructs science.
Mostly it is dogmatists and antirationalists, rather than theists, that try to suppress science.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 4: Patterns and Punctuations in the History of Life, 16: The Great Dying
Permian extinction, 225 million years ago, wiped out half the families of marine life. What could have caused it? Ecology (more habitable area = more species) and Geology (continental drift) offer an answer.
The theory of continental drift explains that all the continents coalesced to form Pangaea during the latest Permian. This reduced the area of shallow seas in two ways:
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
The theory of continental drift explains that all the continents coalesced to form Pangaea during the latest Permian. This reduced the area of shallow seas in two ways:
- Plain "locking" of the continental plates eliminates all the coast at the sutures
- The locking stops the new spreading of plates, sinks the ocean ridges, withdrawing shallow seas from the continents. The overall sea level doesn't need to drop much to reduce the shallow sea area. If it drops enough to expose the continental shelf, most of the world's shallow seas would disappear.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 4: Patterns and Punctuations in the History of Life, 15: The Cambrian Explosion
Cambrian explosion is the "sudden" appearance of a large variety of life forms in the relatively short period of 10 million years about 600 million years ago. Paleontologists have assumed that the puzzling event is the explosion itself. If we reformulate the question, the "explosion" might be explained as the predictable outcome of a Precambrian event (possibly the evolution of a cropping protist).
The diversity of species around the Cambrian explosion follows the familiar sigmoid curve. Seen this way, the "explosion" becomes just the log phase of the curve. This log phase filled up the oceans of the earth. Since then, evolution has produced endless variation on a limited set of basic designs.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
The diversity of species around the Cambrian explosion follows the familiar sigmoid curve. Seen this way, the "explosion" becomes just the log phase of the curve. This log phase filled up the oceans of the earth. Since then, evolution has produced endless variation on a limited set of basic designs.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 4: Patterns and Punctuations in the History of Life, 14: An Unsung Single-Celled Hero
Why are there so many kinds of living things? Theoretical ecology offers an answer.
There aren't any reliable Precambrian fossils of complex multi-celled organisms. About 600 million years ago, most of the major phyla of invertebrate animals appeared within a period of a few million years. Why did this occur? The relationship between predation and diversity can explain this Cambrian "explosion" of life.
Environments devoid of predators have a lot of population but only a few species. The "cropping principle" states that introduction of predators increases the diversity of the environment.
The Cambrian explosion might be due to the evolution of cropping herbivores - single-celled protists that ate the Precambrian algal community that flourished for two and a half billion years. The original cropping protist, the unsung hero of the history of life, might not have been fossilized.
A well-cropped system is maximally diverse.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
There aren't any reliable Precambrian fossils of complex multi-celled organisms. About 600 million years ago, most of the major phyla of invertebrate animals appeared within a period of a few million years. Why did this occur? The relationship between predation and diversity can explain this Cambrian "explosion" of life.
Environments devoid of predators have a lot of population but only a few species. The "cropping principle" states that introduction of predators increases the diversity of the environment.
The Cambrian explosion might be due to the evolution of cropping herbivores - single-celled protists that ate the Precambrian algal community that flourished for two and a half billion years. The original cropping protist, the unsung hero of the history of life, might not have been fossilized.
A well-cropped system is maximally diverse.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 4: Patterns and Punctuations in the History of Life, 13: The Pentagon of Life
The division of life into plants and animals is not good enough (Plantae and Animalia).
Two new kingdoms must be created for single-celled organisms.
Bacteria and blue-green algae have no internal structures, they are called prokaryotes (literally, before nuclei, karyon is greek for "kernel"). Pre-cambrian has been called "the age of blue-green algae". For 2 billion years, blue-green algal mats were the most complicated forms of life on earth.
Cells with internal structures are called eukaryotes, truly nucleate. The eukaryotic cell might have arisen as a family of prokaryotic cells!
The two kingdoms of Monera and Protista are for prokaryotic unicells and eukaryotic unicells respectively. What about fungi? They are not considered animals but they don't photosynthesize as well. They form the fifth and final kingdom.
The two main events that resulted in the diversity of life are:
Two new kingdoms must be created for single-celled organisms.
Bacteria and blue-green algae have no internal structures, they are called prokaryotes (literally, before nuclei, karyon is greek for "kernel"). Pre-cambrian has been called "the age of blue-green algae". For 2 billion years, blue-green algal mats were the most complicated forms of life on earth.
Cells with internal structures are called eukaryotes, truly nucleate. The eukaryotic cell might have arisen as a family of prokaryotic cells!
The two kingdoms of Monera and Protista are for prokaryotic unicells and eukaryotic unicells respectively. What about fungi? They are not considered animals but they don't photosynthesize as well. They form the fifth and final kingdom.
The two main events that resulted in the diversity of life are:
- Evolution of the eukaryotic cell
- Cambrian explosion - the filling of the ecological barrel by an explosive radiation of multicellular eukaryotes
Ever Since Darwin, 3: Odd Organisms and Evolutionary Exemplars, 12: The Problem of Perfection
An animated fish decoy, complete with rhythmically undulating flaps and an "eye" spot, rides atop the rear of the freshwater mussel Lampsilis. The female mussels dump their larvae when real fish approach, attracted by the decoy. Some of the larvae find their way to the gills of the real fish where they grow. This is how Lampsilis reproduces.
Such perfect designs fuel "Intelligent Design" debates. Is this "intelligent design"? Not if there can be an adaptive advantage to the incipient stages of this useful structure.
Preadaptation - functional change with structural continuity - the idea that a feature initially developed for a specific purpose, finds itself "preadapted" and useful for a completely different purpose further in the evolutionary path of the organism.
For example, the undulating flap of Lampsilis might have provided other advantages earlier - like aeration of the larvae.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Such perfect designs fuel "Intelligent Design" debates. Is this "intelligent design"? Not if there can be an adaptive advantage to the incipient stages of this useful structure.
Preadaptation - functional change with structural continuity - the idea that a feature initially developed for a specific purpose, finds itself "preadapted" and useful for a completely different purpose further in the evolutionary path of the organism.
For example, the undulating flap of Lampsilis might have provided other advantages earlier - like aeration of the larvae.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 3: Odd Organisms and Evolutionary Exemplars, 11: Bamboos, Cicadas
A bamboo, named Phyllostachys bambusoides, flowered in China during the year 999. Since then, it has continued to flower and set seed every 120 years. The bamboo does this wherever it lives. How does the bamboo count the passing years between its sexual reproduction?
Light might be the clock - no accurately cycling bamboo grows within 5 degrees of latitude from the equator, where variations in both days and seasons are minimal.
The story of periodical cicadas is even more amazing - they live underground for 17 years, sucking juices from roots. Then, within just a few weeks, millions emerge, become adults, mate, lay their eggs and die.
What advantage does this synchroneity of sex provide?
Cicadas and bamboos are tasty to a wide variety of organisms.
To avoid predation, some animals hide, some taste bad, others grow spines etc. Bamboo seeds and cicadas use a different defense - "predator satiation". Each individual reproduces in synchroneity, and anyone out of step is gobbled up!
This is an unproven but reasonable hypothesis.
Occasional superfluity is one pathway to success.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Light might be the clock - no accurately cycling bamboo grows within 5 degrees of latitude from the equator, where variations in both days and seasons are minimal.
The story of periodical cicadas is even more amazing - they live underground for 17 years, sucking juices from roots. Then, within just a few weeks, millions emerge, become adults, mate, lay their eggs and die.
What advantage does this synchroneity of sex provide?
Cicadas and bamboos are tasty to a wide variety of organisms.
To avoid predation, some animals hide, some taste bad, others grow spines etc. Bamboo seeds and cicadas use a different defense - "predator satiation". Each individual reproduces in synchroneity, and anyone out of step is gobbled up!
This is an unproven but reasonable hypothesis.
Occasional superfluity is one pathway to success.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Friday, April 4, 2008
Ever Since Darwin, 3: Odd Organisms and Evolutionary Exemplars, 10: Why Should a Fly Eat Its Mother
Some insects, like cecidomyian gall midges, reproduce in a weird way in which the offspring devour their mother. Theories of r- and K- selection can help explain this behavior.
Organisms adapt not just by altering their size and shape, but also by adjusting their "life history strategies".
If the environment is not stable, a good 'strategy' is to reproduce as many offspring as you can, as fast as possible, so that at least some will survive. This is r-selection (r- refers to "rate of increase")
Species living in stable environments, near the maximum population the environment can support, have no incentive to reproduce a lot. It's better for them to raise a few, finely tuned offspring. This is K-selection (K- is for "carrying capacity")
The gall midge, which is a tiny fly, mentioned above is an r-strategist.
They reproduce in two ways:
* normal - hatching from an egg after fertilization
* parthenogenetic - no male fertilization, females reproduce as larvae or pupae. Parthenogenetic females don't lay eggs. Their multiple offspring develop within their mother's body, devouring the mother from inside. Two days after the children emerge, their own children are developing to eat them in the same way. We can understand this behavior in terms of r-selection.
If these flies come across mushrooms, their food, they use it to inflate their population using the second method of reproduction. Similar methods of reproduction have independently evolved in several other species - Micromalthus debilis, Mycophila speyeri, Aphids for example.
In contrast, humans are consummate K-strategists.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Organisms adapt not just by altering their size and shape, but also by adjusting their "life history strategies".
If the environment is not stable, a good 'strategy' is to reproduce as many offspring as you can, as fast as possible, so that at least some will survive. This is r-selection (r- refers to "rate of increase")
Species living in stable environments, near the maximum population the environment can support, have no incentive to reproduce a lot. It's better for them to raise a few, finely tuned offspring. This is K-selection (K- is for "carrying capacity")
The gall midge, which is a tiny fly, mentioned above is an r-strategist.
They reproduce in two ways:
* normal - hatching from an egg after fertilization
* parthenogenetic - no male fertilization, females reproduce as larvae or pupae. Parthenogenetic females don't lay eggs. Their multiple offspring develop within their mother's body, devouring the mother from inside. Two days after the children emerge, their own children are developing to eat them in the same way. We can understand this behavior in terms of r-selection.
If these flies come across mushrooms, their food, they use it to inflate their population using the second method of reproduction. Similar methods of reproduction have independently evolved in several other species - Micromalthus debilis, Mycophila speyeri, Aphids for example.
In contrast, humans are consummate K-strategists.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Wednesday, April 2, 2008
Ever Since Darwin, 3: Odd Organisms and Evolutionary Exemplars, 9: The Misunderstood Irish Elk
Irish Elk is neither exclusively Irish, not is it an elk.
It's the largest deer that ever lived.
Reliable estimates of their total antler span range up to 12 feet.
It evolved during the glacial period of the last few million years and became extinct in Ireland around 11000 years ago (but may have survived to historic times in continental Europe).
Why did such huge antlers evolve? What was the adaptive advantage they provided?
They served as "visual dominance-rank symbols". Mostly for display/ritualized combat, not as weapons.
If the antlers are adaptive, why did the deer become extinct?
The giant deer flourished in Ireland for a very brief warm period (between two colder epochs) of about 1000 years, 12000 to 11000 years before the present. They were well adapted for the glassy, sparsely wooded, open country of this time but probably could not adapt fast enough for the subarctic tundra that followed, or to the heavy forestation that developed after the final retreat of the ice sheet.
Darwinian evolution decrees that no animal shall actively develop a harmful structure, but it offers no guarantee that useful structures will continue to be adaptive in changed environments.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
It's the largest deer that ever lived.
Reliable estimates of their total antler span range up to 12 feet.
It evolved during the glacial period of the last few million years and became extinct in Ireland around 11000 years ago (but may have survived to historic times in continental Europe).
Why did such huge antlers evolve? What was the adaptive advantage they provided?
They served as "visual dominance-rank symbols". Mostly for display/ritualized combat, not as weapons.
If the antlers are adaptive, why did the deer become extinct?
The giant deer flourished in Ireland for a very brief warm period (between two colder epochs) of about 1000 years, 12000 to 11000 years before the present. They were well adapted for the glassy, sparsely wooded, open country of this time but probably could not adapt fast enough for the subarctic tundra that followed, or to the heavy forestation that developed after the final retreat of the ice sheet.
Darwinian evolution decrees that no animal shall actively develop a harmful structure, but it offers no guarantee that useful structures will continue to be adaptive in changed environments.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Monday, March 31, 2008
Ever Since Darwin, 2: Human Evolution, 8: Human Babies as Embryos
Altricial mammals - large, helpless litters
Precocial mammals - small, able litters
What about us? Humans have small litters that are helpless! Why?
Answer -> Human babies are born as embryos, and they remain so for the next 9 months of their life.
If we measure time according to the rate of metabolism, almost all mammals live for the same amount of "time". For example, all mammals breathe the same number of times. Small, short-lived mammals just breathe (and metabolize) faster. By this relative measure of time, human gestation should take around 18 months.
Then why do births occur after just 9 months? Is it because we need the next 9 months to get familiar with the sights and sounds of the real world? No, the reason is more likely to be "mechanical". The culprit is our large brain. It would be hard for a delivery to happen if the brain became any larger!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Precocial mammals - small, able litters
What about us? Humans have small litters that are helpless! Why?
Answer -> Human babies are born as embryos, and they remain so for the next 9 months of their life.
If we measure time according to the rate of metabolism, almost all mammals live for the same amount of "time". For example, all mammals breathe the same number of times. Small, short-lived mammals just breathe (and metabolize) faster. By this relative measure of time, human gestation should take around 18 months.
Then why do births occur after just 9 months? Is it because we need the next 9 months to get familiar with the sights and sounds of the real world? No, the reason is more likely to be "mechanical". The culprit is our large brain. It would be hard for a delivery to happen if the brain became any larger!
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Sunday, March 30, 2008
Ever Since Darwin, 2: Human Evolution, 7: The Child as Man's Real Father
We evolved by retaining the youthful characters of our ancestors.
This process is called neoteny (literally, "holding youth")
Many of our adult features are similar to the juvenile features of other primates.
This delayed development is a basic event in human (and primate) evolution.
We live longer and mature more slowly than mammals of comparable body size.
Humans have the most protracted period of infancy, childhood and juvenility.
Nearly 30% of our life is spent growing.
What is the adaptive significant of retarded development?
Humans are not particularly strong, swift or well-designed. We don't reproduce rapidly.
We are a learning animal and our primary advantage is our brain.
To enhance our learning, we have lengthened our childhood by delaying sexual maturation with its adolescent yearning for independence. Our children are tied for longer periods to their parents, increasing their learning time and strengthening family ties.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
This process is called neoteny (literally, "holding youth")
Many of our adult features are similar to the juvenile features of other primates.
This delayed development is a basic event in human (and primate) evolution.
We live longer and mature more slowly than mammals of comparable body size.
Humans have the most protracted period of infancy, childhood and juvenility.
Nearly 30% of our life is spent growing.
What is the adaptive significant of retarded development?
Humans are not particularly strong, swift or well-designed. We don't reproduce rapidly.
We are a learning animal and our primary advantage is our brain.
To enhance our learning, we have lengthened our childhood by delaying sexual maturation with its adolescent yearning for independence. Our children are tied for longer periods to their parents, increasing their learning time and strengthening family ties.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 2: Human Evolution, 6: Bushes and Ladders
A ladder is not the right metaphor for evolution. A bush is.
New species arise in very small populations that become isolated from their parental group at the periphery of the ancestral range, the "bush". Speciation in these branched groups is very fast by evolutionary standards - hundreds or thousands of years (a geological microsecond).
The steps of this speciation might not be captured in fossils since it happens very fast. We encounter the new species when it reinvades the ancestral range and becomes a major population by itself. The process repeats and we find "sudden" changes in fossil records.
There were several co-existing brances of the human bush. We are merely the surviving branch.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
New species arise in very small populations that become isolated from their parental group at the periphery of the ancestral range, the "bush". Speciation in these branched groups is very fast by evolutionary standards - hundreds or thousands of years (a geological microsecond).
The steps of this speciation might not be captured in fossils since it happens very fast. We encounter the new species when it reinvades the ancestral range and becomes a major population by itself. The process repeats and we find "sudden" changes in fossil records.
There were several co-existing brances of the human bush. We are merely the surviving branch.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 2: Human Evolution, 5: A Matter of Degree
We only have differences in degree (of features) with chimpanzees, there are no unambiguous differences of kind. We differ just quantitatively, not qualitatively.
The genetic distance between us and chimps is very small (small enough that interbreeding might be possible). Then why the vast differences in form and behavior? Genes do not just determine traits. During development, different genes must turn on and off with exquisite timing to achieve differences from the same genetic system. For example, when a hand forms from a homogeneous limb bud, cells must proliferate in some areas (destined to be fingers) and die in others (the spaces between them).
We have genetic differences most likely in regulatory genes, that control this timing, resulting in large differences with only a few (relatively) differing genes.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
The genetic distance between us and chimps is very small (small enough that interbreeding might be possible). Then why the vast differences in form and behavior? Genes do not just determine traits. During development, different genes must turn on and off with exquisite timing to achieve differences from the same genetic system. For example, when a hand forms from a homogeneous limb bud, cells must proliferate in some areas (destined to be fingers) and die in others (the spaces between them).
We have genetic differences most likely in regulatory genes, that control this timing, resulting in large differences with only a few (relatively) differing genes.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 1: Darwiniana, 4: Darwin's Untimely Burial
Darwin's theory of natural selection has been a perennial candidate for burial.
Does the theory have a logical error in its formulation?
Natural selection was defined by Herbert Spencer as "survival of the fittest".
Is fitness just "differential reproductive success"?
If fitness is defined in terms of survival, Spencer's phrase becomes a tautology - "survival of those who survive".
Darwin did propose an independent criterion but relied upon an analogy - artificial selection of the fittest by animal breeders. But nature is no animal breeder. How is the analogy valid?
The breeder's priorities represent a "change in environment" for the animals. Superior design in changed environments is an independent criterion of fitness. Thus, survival is a result of fitness, not a definition of it.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Does the theory have a logical error in its formulation?
Natural selection was defined by Herbert Spencer as "survival of the fittest".
Is fitness just "differential reproductive success"?
If fitness is defined in terms of survival, Spencer's phrase becomes a tautology - "survival of those who survive".
Darwin did propose an independent criterion but relied upon an analogy - artificial selection of the fittest by animal breeders. But nature is no animal breeder. How is the analogy valid?
The breeder's priorities represent a "change in environment" for the animals. Superior design in changed environments is an independent criterion of fitness. Thus, survival is a result of fitness, not a definition of it.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Friday, March 28, 2008
Ever Since Darwin, 1: Darwiniana, 3: Darwin's Dilemma: The Odyssey of Evolution
Darwin, Lamarck and Haeckel - the greatest 19th century evolutionists of England, France and Germany respectively - did not use the word evolution in the original editions of their great works.
Evolution had another technical meaning in Darwin's time - a theory that all future generations existed, like Russian dolls, in the ova of Eve or sperm of Adam. Latin evolvere means "to unroll".
However, by 1859, evolution was losing this meaning. It had become a common English word and embodied a concept of progressive development. It was available as a description for Darwin's "descent with modification".
Darwin, though, did not like the term evolution because he was uncomfortable with the notion of inevitable progress inherent in its vernacular meaning. Darwin stood almost alone in insisting that organic change led only to increasing adaptation between organisms and their own environment and not to an abstract ideal of progress - never say higher or lower.
Evolution has no necessary links to progress. Scientists know this but most laymen still associate evolution with progress, not simply as change.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Evolution had another technical meaning in Darwin's time - a theory that all future generations existed, like Russian dolls, in the ova of Eve or sperm of Adam. Latin evolvere means "to unroll".
However, by 1859, evolution was losing this meaning. It had become a common English word and embodied a concept of progressive development. It was available as a description for Darwin's "descent with modification".
Darwin, though, did not like the term evolution because he was uncomfortable with the notion of inevitable progress inherent in its vernacular meaning. Darwin stood almost alone in insisting that organic change led only to increasing adaptation between organisms and their own environment and not to an abstract ideal of progress - never say higher or lower.
Evolution has no necessary links to progress. Scientists know this but most laymen still associate evolution with progress, not simply as change.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Ever Since Darwin, 1: Darwiniana, 2: Darwin's Sea Change or Five Years at the Captain's Table
Trick question: Who was the naturalist aboard the H.M.S. Beagle?
Answer: Not Darwin, the official naturalist was the ship's surgeon, Robert McKormick, even though Darwin's efforts began to outstrip his collections, forcing McKormick to go home.
In those days, British naval tradition dictated that a captain have virtually no contact with anyone down the chain of command. These voyages lasting many years, with only a very limited contact by mail with friends and families, can exert a heavy psychological toll. The previous captain of Beagle had shot himself to death during his third year away from home. Darwin sailed on the Beagle as a companion to Captain Fitzroy since he had the right social standing.
Fitzroy believed in "god's design" while Darwin proposed a natural explanation for the perfection of organic structure. Discussions with Fitzroy while dining with him every day for five years, without being able to rebuke him, might have been more important than the finches of Galapagos in inspiring the materialistic and antitheistic tone of Darwin's philosophy and evolutionary theory. For five long years, one of the most brilliant men in recorded history kept his peace.
After the voyage, Fitzroy began to see himself as the unwitting agent of Darwin's heresy. He shot himself eventually.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Answer: Not Darwin, the official naturalist was the ship's surgeon, Robert McKormick, even though Darwin's efforts began to outstrip his collections, forcing McKormick to go home.
In those days, British naval tradition dictated that a captain have virtually no contact with anyone down the chain of command. These voyages lasting many years, with only a very limited contact by mail with friends and families, can exert a heavy psychological toll. The previous captain of Beagle had shot himself to death during his third year away from home. Darwin sailed on the Beagle as a companion to Captain Fitzroy since he had the right social standing.
Fitzroy believed in "god's design" while Darwin proposed a natural explanation for the perfection of organic structure. Discussions with Fitzroy while dining with him every day for five years, without being able to rebuke him, might have been more important than the finches of Galapagos in inspiring the materialistic and antitheistic tone of Darwin's philosophy and evolutionary theory. For five long years, one of the most brilliant men in recorded history kept his peace.
After the voyage, Fitzroy began to see himself as the unwitting agent of Darwin's heresy. He shot himself eventually.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
Thursday, March 27, 2008
Ever Since Darwin, 1: Darwiniana, 1: Darwin's Delay
Darwin developed his theory of evolution in 1838 but published it 21 years later. Why? Was he afraid of sounding heretical? No, evolution was a heresy but a common and well-discussed one.
He was afraid of exposing something far more heretical: Philosophical Materialism - the idea that matter is the stuff of all existence and all mental and spiritual phenomena are its by-products.
The most ardent materialists of the 19th century, Marx and Engels, recognized Darwin's accomplishment. In fact, Marx offered to dedicate volume 2 of Das Kapital to Darwin (who declined since he hadn't read the German work)
Darwin eventually published The Origin of Species in 1869 but only because A. R. Wallace was about to scoop him.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
He was afraid of exposing something far more heretical: Philosophical Materialism - the idea that matter is the stuff of all existence and all mental and spiritual phenomena are its by-products.
The most ardent materialists of the 19th century, Marx and Engels, recognized Darwin's accomplishment. In fact, Marx offered to dedicate volume 2 of Das Kapital to Darwin (who declined since he hadn't read the German work)
Darwin eventually published The Origin of Species in 1869 but only because A. R. Wallace was about to scoop him.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
The Colossal Book of Mathematics by Martin Gardner
This is a book of recreational mathematics. I could not finish this book as I had to return it to library. Some of the sections in the book that are of interest are (directly from my notebook):
1. Rep-n Polygons
2. Piet Heins Superellipse
Super Egg - Exponent 2-1/2 . Columbus experiment of making an egg stand
Interesting Fact: If Center of Curvature is above Center of Gravity the superegg will be stable -P69 -> Wiki
3. Planiverse - 2D universe - very interesting depiction of men and women
4. Helix and its importance - The shape is everywhere - shapes of nut & bolts , horns ,sea shells, snails shells, DNA molecules -> can be both right handed and left handed
5. Spheres & Hyperspheres
137 -> a2+b2+c2+d2=r2 is called hypersphere in 4 dimensions
surface of a n-sphere has a dimensionality of n-1. Does this mean that 3-space is actually the hypersurface of the vast 4-sphere.
If space is a hypersphere, then that hypersphere must sit in a four-dimensional Euclidean space, allowing us to view it from the outside. Nature, however, need not cling to this notion. It would be perfectly acceptable for the universe to be a hypersphere and not be embedded in any higher-dimensional space. Such an object may be difficult to visualize, because we are used to viewing shapes from the outside. But there need not be an "outside."
Good Explanation: Paradigm Shifts in Astronomy and Cosmology - More
6. The Church of Fourth Dimension
I had to stop here. I will provide some updates on more sections once I get the book back.
The Colossal Book of Mathematics>
1. Rep-n Polygons
2. Piet Heins Superellipse
Super Egg - Exponent 2-1/2 . Columbus experiment of making an egg stand
Interesting Fact: If Center of Curvature is above Center of Gravity the superegg will be stable -P69 -> Wiki
3. Planiverse - 2D universe - very interesting depiction of men and women
4. Helix and its importance - The shape is everywhere - shapes of nut & bolts , horns ,sea shells, snails shells, DNA molecules -> can be both right handed and left handed
5. Spheres & Hyperspheres
137 -> a2+b2+c2+d2=r2 is called hypersphere in 4 dimensions
surface of a n-sphere has a dimensionality of n-1. Does this mean that 3-space is actually the hypersurface of the vast 4-sphere.
If space is a hypersphere, then that hypersphere must sit in a four-dimensional Euclidean space, allowing us to view it from the outside. Nature, however, need not cling to this notion. It would be perfectly acceptable for the universe to be a hypersphere and not be embedded in any higher-dimensional space. Such an object may be difficult to visualize, because we are used to viewing shapes from the outside. But there need not be an "outside."
Good Explanation: Paradigm Shifts in Astronomy and Cosmology - More
6. The Church of Fourth Dimension
I had to stop here. I will provide some updates on more sections once I get the book back.
The Colossal Book of Mathematics>
Ever Since Darwin, Prologue
Darwin convinced the thinking world, within a decade, that evolution had occurred but his own theory of natural selection didn't prevail until the 1940s. Even today it is misunderstood.
However, natural selection is just two facts and one conclusion:
* organisms vary and the variations are inherited (at least in part) by their offspring
* organisms produce more offspring than can possibly survive
=> Organisms varying in directions favored by the environment will survive and propagate.
Darwin contended that natural selection is a creative force, not just an executioner of the unfit. It must construct the fit as well. This is accomplished by small, random variations that are not predirected in favorable ways.
Evolution is a mixture of chance and necessity - chance at the level of variation, necessity in the level of selection.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
However, natural selection is just two facts and one conclusion:
* organisms vary and the variations are inherited (at least in part) by their offspring
* organisms produce more offspring than can possibly survive
=> Organisms varying in directions favored by the environment will survive and propagate.
Darwin contended that natural selection is a creative force, not just an executioner of the unfit. It must construct the fit as well. This is accomplished by small, random variations that are not predirected in favorable ways.
Evolution is a mixture of chance and necessity - chance at the level of variation, necessity in the level of selection.
Ever Since Darwin: Reflections in Natural History by Stephen Jay Gould
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