Stuff I Wish I Had Read When I Was Younger

6 11 2010

Over the years I have supervised and mentored several PhD students, and recently our firm started to award scholarships to undergrads, and I was asked to support one such scholar. These scholars are from the best and brightest and so I got to thinking…

Graduates today have it tough, competition is tough, people work longer and harder than ever and stress is hitting us earlier and earlier in life – or so it seems. I would argue that, to some real extent, things have always been getting worse, and therefore by induction, we can prove that they have haven’t really changed at all.

No, the graduates of today have unparalleled opportunity to learn, to travel and to experience. The brightest graduates have the world at their feet and will be its commanders when we are are all retired and done for.

So what could I do to support this scholar? In the end it was easy – I asked myself – what do I know now that I wish I had known sooner? Most of this is in attitudes and is deep in my psychology, and is the result of direct experience – but it turns out that a healthy chunk of my scientific learning experience can be re-lived – by reading some of the books I think steered my course.

So I made a point to summarize some of the best science related books I have read (and some of the most useful internet resources I have found), and dumped the list complete with hyper-links in an email to the scholar. I hope she goes on to be president!

Now having gone to the effort, it would be a crime to keep this email secret, so here it is, (almost) verbatim!

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As promised, here is a list of useful resources I wish I had known about when I was an undergrad. I am glad I got round to this, it should be useful for several other students I work with, and has also led to me revisiting a few things! I think I may brush it up and pop in on my blog if you don’t mind…obviously I won’t mention you!
Anyway, back to the business. To me, science is not all about chemistry, molecules, atoms, valence electrons and so on. To me, is is the process of trying to understand the world, and this set of materials I have hand picked, should you get through even a part of it, will not only educate but inspire.

This may not be the very best list, and I am sure there are many great books I have not read, but I have stuck with ones that I have, so you will have to rely on other people for further recommendations.

Jarrod’s reading list: science/psychology/economics & so on

  • I’ll start with something really easy, relevant and engaging – an excellent (if quirky) summary of material science: The New Science of Strong Materials – Prof Gordon  has written another on Structures that is also worth reading.
  • Ok, this next one is not a book, but a paper; I like it because it shows that many stuffy professors are wrong when they prescribe boring scientific prose for papers. This paper uses the criminal “us” and “we” and discusses subjects as if with a friend. Shocking form, especially for a junior scientist. This paper by an unknown, changed the world.
  • Guns, Germs and Steel” – this is large-scale scientific thinking at its best- the book looks at how we can explain why the world is the way it is (especially the inequality) by looking at how technology spreads through societies.
  • Mistakes were made…but not by me” – this is required reading if you want to work with other people, so its basically for everyone then…
  • Then to take it to the next level – “How the mind works…” – Stephen Pinker‘s other books are also good if you like this one.
  • “Flatland”, (full text here) was written in 1884, and is essential reading because it defines the cliche “thinking outside of the box”.
  • To make your upcoming economics courses more interesting, first read this easy-to-read popular book: “The Undercover Economist“.
  • Also, Freakonomics– it’s shameless self promotion by egotistical authors, but hell they are smart, so put up with it.
  • The Tipping Point –  Malcolm Gladwell is a current thinker I really like; he’s not satisfied to focus on one thing for very long – his other books are on totally different stuff, but are equally thought provoking.
  • The selfish gene” – Obviously I would firstly recommend “On the Origin of Species”, (full text here) but if you are short of time (which you should be as an undergrad), you can learn most of the basics, and also get updated (well up to the 1970’s at any rate) by reading Dawkins’ classic.
  • I couldn’t ignore statistics, so I will include two – one classic, “How to Lie with Statistics”  and a more modern one “Reckoning with Risk“, they are quite different, but either will get the important points across.

Alas, books are perhaps becoming obsolete, so I better include some other media:-

  • The first one is so good I can’t believe its free – try watch at least one a week, but the odd binge is essential too. http://www.ted.com/
  • Next, an excellent physics recap (or primer) – but  you need lots of time (or a long commute!) to get through this lot – look on the left menu for Podacts/Webcasts on this webpage: http://muller.lbl.gov/teaching/physics10/pffp.html – I cannot begin to praise the worthwhileness of this enough. It used to be called “Physics for future presidents” because it teaches you enough to understand the risks of nuclear energy, and the likelihood that we will all run our cars on water – and let you know when you are being duped or dazzled by big words.
  • When I was somewhat younger there was a TV show called Cosmos, hosted by Carl Sagan, you may know of it. You could watch in now here, though obviously it is dated, so perhaps you shouldn’t; the reason I mention it, is because it was key in creating a generation of scientists, people who were inspired by Carl to be inspired by the universe. The previous generation had the space race and the moon landings to inspire them, but since then science has been on a downhill, with 3-mile island, global warming, etc, etc, and we have had no more Carl Sagans to cheer for us; Cosmos was a rare bit of resistance in the decline of the importance of science in society. You may also know that there have been battles in society (well in the circles on intelligentsia at any rate) about science – on the one had the ‘two cultures debate‘ and more recently, the ‘anti-science’ movement (suggested in books like “The Republican War on Science“. I do not wish to indoctrinate you, but rather make you aware that being a scientist used to be cooler and used to be more respected and something is indeed rotten in the state of Denmark.
  • Getting back on track, here is an excellent guide to critical thinking (something else sadly lacking in the world) – don’t read it, listen to the podcast versions (also on itunes):
    “A Magical Journey through the Land of Logical Fallacies” – Part 1 and Part 2
    I think this should be taught in school. Brian Dunning’s other Skeptoid podcasts put these lessons into practice showing how a scientific approach can debunk an awful lot of the nonsense that is out there (alternative medicine, water dowsers, fortune tellers, ghost hunters, etc etc).
  • If you do happen to have any time left, which I doubt, there are several other podcasts on critical thinking – that use a scientific approach to look at the world and current affairs: –

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Postscipt – Dear readers, please feel free to append your own recommendations to my letter in the comments section below. If there is one thing I know well, and that’s how little I know. I feel I only started to read ‘the good stuff’ far too late in life, and so those with more years than me (or better mentors), please do share. But bear in mind, this is principally a science oriented list, and is meant to be accessible to undergraduates – I left out books like Principia Mathematica (Newton) because it is really rather unreadable – and the Princeton Science Library (though awesome) is probably a bit too intense. Also, in the 30 minutes since I sent the email, I have already thought of several others I sort of, well, forgot:

That’s it for now…

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Confessions of Scientific Atheist

31 05 2010

The Evolutionary theory of Natural Selection makes extraordinary claims. It explains the ability of creatures to convert sunlight to useful energy, to spin silk, to metabolise sulfurous rock – and much more besides.

Such amazing feats in nature require an amazing explanation. The existence of a God is very helpful in this regard; after all, humans have designed diesel cars and digital computers, so why couldn’t an entity with God’s power and talent create all the nature we see?

The trouble many people have with Natural Selection, is that while it can clearly explain some biology, using it to explain away practically all biology (and psychology, language, culture, etc.)  is an extrapolation – and a big one at that.

Why do scientists allow such an extrapolation? Surely this is arrogance?

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Thinking about this, I have an proposition…

If you come from the premise that there is nothing outside of nature (see my recent post), then it comes easily. If the God option is written off a priori, we have no other logical option than to expect that the gaps in our knowledge of evolution will be filled in eventually. This allows us to sleep at night with the extraordinary.

If you start from the premise that there is a God, then this will strike you are arrogant.

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The constant supply of greater details, filling in the gaps, gives encouragement to those who feel the theory is right (see God of the Gaps). It’s a bit like looking for Nessy – we can’t do a Star-Trek style ‘scan for lifeforms’ to be sure she does not exist, but the more we search the less likely she is to exist.

Of course, while evolution explaining away the wondrous variety in life does not prove there is no God, it sure makes God less necessary, and less necessarily capable.





What exactly is ‘science’?

14 05 2010

I used to think science was the practice of the scientific method; i.e. you propose a hypothesis, you develop a test of the hypothesis, execute it and prove the hypothesis.

That worked for me until the end of high school.

At university, I was a true nerd. I read all my textbooks cover to cover (mainly because as I was too shy for girls and too poor for booze). During this time, the definition above started to fail. So much of the science was maths, statistics, observation, pattern recognition, logic and quite a bit of rote learning. Not all of it fitted into my definition of science. I became a fan of a new definition: science is the study of the nature of reality .

But then I did post-grad, and I realised that not much in science is ‘proven’ (I guess this is the point of post grad study). Evolution, for example, is not proven. That the sun revolves around the earth is not ‘proven’. I discovered that the only things that could be proven were ‘ideas’ about ‘other ideas’. Bear with me on this one.

Let us say we define the number system – this is an ‘idea’ or conceptual construction. Within this construction we can ‘prove’ that one and one is two. Because we ‘made’ the system, with rules, then we can make factual and true statements about it. We can’t do this about the real world – we cannot say anything with absolute certainly because we rely on flaky inputs like our own highly fallible perception.

It’s like that old chestnut: how can you be sure you are not living in a giant simulation? Of course you can argue that it is pretty unlikely and I would agree, and right there we have a clue to a better definition of science.

It turns out that much of modern science deals in ‘likelihood’ and ‘probability’ rather than proof and certainty. For example, we can say that the theory of evolution is very likely to be more-or-less right, as there is a lot of corroborating evidence. Science cannot be run like a law court – where the prosecution only need to reach a threshold of reasonable doubt to ‘prove’ someone guilty.

Aside for nerds: Science says you can use logic to prove things absolutely, but logic only works with ideas, and there is a breakdown between ideas and reality, so one can never prove things in reality. So it is thoroughly wrong for a court to say that someone has been proven guilty. The courts use this language as a convenience, to “draw a line under” a case as they have not found a moral way to dole out punishments based on probabilities. Imagine a world in which a murder suspect gets a 5 year sentence because the was a 20% chance he was guilty! Sports referees often operate in this decisive way, perhaps because it saves a lot of arguing!

Anyway, good science cannot just give up and say once there is consensus something passes from theory to fact. This is sloppy. We have to keep our options open – forever.

Think for example of Newton’s Laws of Motion. They are called ‘Laws’ because the scientific community had so much faith in them they passed from theory (or a proposed model) to accepted fact. But they were then found wrong. Strange that we persist in calling them laws!

It took Einstein’s courage (and open mindedness) to try out theories that dispensed with a key plank of the laws – that time was utterly inflexible and completely constant and reliable.

So it is that the canon of scientific knowledge has become a complex web of evidence and theories that attempt to ‘best fit’ the evidence.

Alas, there are still many propositions that many so-called scientists would claim are fact or at least ‘above reproach’. Evolution is attacked (rather pathetically), but the defenders would do well to take care before they call it ‘fact’. It is not fact, it is a superbly good explanation for the evidence, which has yet to fail a test of its predictions. So it is very very likely to be right, but it cannot be said to be fact.

This is not just a point of pedantry (though I am a bit of a pedant) – it is critical to keep this in mind as it is the key to improving our model.

Two great examples of models people forget are still in flux…

1) The big bang theory

2) Quantum theory

I will not go into global warming here though it is tempting. That is one where it doesn’t even matter if it is fact, because game theory tells you that either way, we better stop making CO2 urgently.

Back to the big bang.

I heard on the Skeptic’s Guide podcast today about an NSF questionnaire that quizzed people about whether they believed the universe was started with a massive explosion, and they tried to paint the picture that if you didn’t believe that, then you were ignorant of science. This annoyed me, because the big bang theory is now too often spoken of as if it were fact. Yes, the theory contributes viable explanations for red-shifted pulsars, background radiation, etc, etc, but people are quick to forget that it is an extrapolation relying on a fairly tall pile of suppositions.

I am not saying it is wrong, all I am saying is that it would be crazy to stop exploring other possibilities at this point.

You get a feeling for the sort of doubts you should have from the following thought experiment:

Imagine you are a photon born in the big bang. You have no mass, so you cannot help but travel at ‘light speed’. But being an obedient photon, you obey the contractions in the Lorentz equations to the letter, and time thus cannot pass for you. However, you are minding your own business one day when suddenly you zoom down toward planet earth and head straight into a big radiotelescope. Scientists analyse you and declare that you are background radiation dating from the big bang and that you have been travelling for over 13 billion years (they know this because they can backtrack the expansion of the universe). Only trouble is, that for you, no time has passed, so for you, the universe is still new. Who is right? What about a particle that was travelling at 0.999 x the speed of light since the big bang? For it, the universe is some other intermediate age. So how old is the universe, really?

This reminds us of the fundamental proposition of relatively – time is like a gooey compressible stretchable mess, and so is space, so the distance across the universe may be 13.5 billion light years, or it might be a micron (how it felt to the photon). It all depends on your perspective. It is much like the statement that the sun does not revolve around the earth and that it is the other way around. No! The sun does revolve a round the earth. You can see it clearly does. From our perspective at least.

Now, quantum theory.

Where do I start? String theory? Entanglement? Please.

The study of forces, particles, EM radiation and the like is the most exciting part of science. But being so complex, so mysterious, so weird and counter intuitive, it is super vulnerable to abuse.

Most people have no idea how to judge the merits of quantum theories. Physicists are so deep in there, they have little time (or desire or capability) to explain themselves. They also love the mystique.

I do not want to ingratiate myself with physicists, so I will add that the vast majority have complete integrity. They do want to understand and then share. However, I have been working in the field for long enough to know that there are weaknesses, holes and downright contradictions in the modern theory that are often underplayed. In fact these weaknesses are what make the field so attractive to people like me, but is also a dirty little secret.

The fact is that the three forces (weak nuclear, strong nuclear and magnetic) have not been explained anything like as well as gravity has (by relativity). And don’t get me started on quantum gravity.

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Anyway, thinking about all these issues, I concluded that science was (definition #3) the grand (platonic) model we are building of reality, ever evolving to best fit our observations.

My man, Plato

That works well for me. However, I recently came across a totally different definition for science:

# 4) “Science is a tool to help make the subjective objective.”

OK I paraphrased it to make it more snappy. It was really a discussion about how science was developed to overcome the fallibility of the human mind. Examples of weaknesses it needs to overcome are:

  1. The way our perception is filtered by preconceptions
  2. How we see pattern where there is none
  3. How we select evidence to match our opinion (confirmation bias)
  4. How we  read too much into anecdotal evidence
  5. etc etc.

I could go on. So ‘science’ is the collection of tricks we use to overcome our weaknesses.

I like this definition. We are all going about, and in our heads we are building our model of the world… and its time for an audit!





Evolution in the toilet bowl

2 04 2010

No, this blog is not about how evolution theory is going down the toilet, crushed in the cold grip of reason by The Discovery Institute.

This blog is about how toilet bowls can be used to show speciation forces at work [speciation – the birth of new species].

You see, I have just recently moved to the US, and have noticed the toilets here exhibit characteristics different to their UK and European cousins. Most specifically, US toilets are filled far higher with water and the water surface is greatly increased in diameter. Furthermore, the flush-handles in the US are more often on the left, rather than on the right as they are in the UK.

How can it be in such a small and networked world, such a speciation could occur and indeed survive?

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A short stroll on the ‘net does not reveal much about how Americans came to prefer deep water, so I will have a guess. Presumably some big brand (like American Standard) was strongly dominant and the flagship model offered deeper water –  perhaps to prevent skid-marks, or maybe to ensure ‘complete submersion’. As this brand was so strong it was copied, and became the standard. Time passed, and now the average american might turn their nose up at the European low-level option (or indeed the interesting Asian options).

Question: When a European sees an American toilet, are they amazed at its superiority?

No. People don’t like change – and the deep American version is probably not actually any better. For example, the chance of urine splashing on the seat (or on one’s rear for those sitting) is increased, and so therefore, if anything, I would say the ‘deep dish’ is inferior.

So what does this say about evolution? It shows how a contraption, in different environments, will evolve to become different. But more interesting (to me at least) is that Americans and Europeans are not really significantly different and thus the pressures at play were really rather random. It is not as it American toilets have evolved to be stronger because Americans are larger (that would be no surprise) –  this ‘depth’ evolution is different – and very real, but the result of an almost random mutation (of the water depth) that is perhaps not any fitter, just different, and it has survived, despite its weaknesses, due to its isolation across the pond.

What I am saying is that in replicating systems, things will drift apart (there is a natural divergence) on a fast time scale, and the survival of a trait is on a longer time scale. Perhaps in 200 years time we will see no more deep toilets, but right now we have a new species.

Thus I propose you may actually get speciation from drift alone without fitness actually being tested.

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So will a device that gently catches one’s emissions and silently whisks them away, instantly, with no splashing, odour, mess or need to flush will supplant the lot? No, because it will probably be expensive, and this cost pressure will always ensure room in the ‘ecosystem’ for multiple solutions – the “two planks over a ditch’ option will always be around because it is so cheap and simple.

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Anyway,  next time you go, think about what the toilet might teach us about the subtler aspects of evolution by selection. It’s valuable thinking time after all!  🙂

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Epilogue: an aside on valves…

There are obviously several competing technologies for the flush valve, and none has proven clearly superior; so the fact that the US does not (in my short experience) have a very high penetration of the siphon valve (‘claimed’ by Thomas Crapper), does not surprise me. It is indeed much more leak-proof than the popular ‘flapper’ valve, but more complex and thus prone to breakdown. However, the newly popular half-flush siphon valve, which can be easily retrofitted looks to be a clear leap in its evolution. Competition is hot though, and heading to the US, we will wait with bated breath to see which technology wins out 😉

Some references:

http://www.toiletology.com/ – some history

http://en.wikipedia.org/wiki/Thomas_Crapper – the famous inventor of certain improvements

Environmental pressures are a new force in the future evolution of the toilet. First we had the dual flush, now we have the “No Mix” toilet that keeps 1’s and 2’s apart for tailored treatment! http://www.sciencedaily.com/releases/2010/03/100310134258.htm





The Apple Mac: It’s a religion…

6 02 2010

It has been explained by writers better than I how our minds are wired in a way that makes them vulnerable to religion.

Whether it is our desire to feel secure or have simple and complete explanations for natural phenomena or simply because we enjoy the social scene at church, there is no doubting the power of the effect. Even in modern times, entire lives, indeed entire civilizations are devoted to the superstitious concept of supernatural Gods.

Although L. Ron Hubbard may have started a religion while knowing it was all a sham, most religions did not need such deliberate action. Our innate need to have faith in things has allowed religious concepts to emerge and evolve freely in our communities as far back as records go.

So why do I bring that up?

It occurred to me today while pondering why people are so defensive about Apple Mac computers – I realised that their behaviour had much in common with religious ‘zeal’.

Then it occurred to me how much the success of Apple relies on perception and conception. If it was just about getting the fastest computer, you would not buy a Mac. If it was about buying something that has wide compatibility, you would not buy a Mac. If it was about cost, you certainly would not buy a Mac.

Some might argue that Macs are more intuitive and ‘easy to use’. These are people whose idea of computing is buying a shiny box, plugging it in and doing exactly what they are expected to do. They are people who just accept it when they are told they need to buy a new printer. Or worse, they blame the printer – what a crappy printer, not compatible! These are people who do not need to set up a complex network, or run a database server.

Anyone who has a Powerbook G4 that cost several grand and is not actually compatible with the latest OSX release, yet needs that OSX release in order to actually work, and still hugs and caresses the machine as it it were a newborn baby while defending its honour and wanting to spend another several grand on a newer shinier one, is, in my opinion, dabbling in a cult.

OK, before you write me off as some sort of anti-mac fanatic, I will admit they are beautiful.

Moving swiftly on, I think it is worth analysing Apple’s success.

How does a company that controls the details of their products so completely compete with a product (the PC) that is made by hundreds of companies all constantly competing, innovating, coming and going, rising and falling? The modular design of the PC allows almost anyone to buy all the bits and assemble the machine themselves; with so many companies making monitors and keyboards and hard drives, some will make bad (fatal) decisions and die, some will make good decisions and thrive and if there are enough upstarts to keep up the supply, the consumer will only ever see the winners, even if their victory was a flook, it was a victory none the less.

You could say that PC is the computer you get from natural selection (survival of the fittest), the Mac is the the computer you get when you try to control the evolution (unnatural selection).

Now a company that tries to make everything itself can capture the value chain, sure, but as it is only one company, it cannot make even one fatal decision, and thus needs to be a little more cautious. This means it is doomed to always lag slightly on the performance vs value curve – so what does it do?

Easy, get the consumer to accept poor value. Make up for performance by buying in high quality technologies (lcd screens, hard disks, etc), and make the customer pay the premium. Then focus on marketing.

Marketing is the art of making people want something. It is unnecessary for products people need.

So what happened at Apple?

Apple, perhaps by good luck, became perceived as a David vs the Goliaths of IBM and Microsoft. For some reason (was it deliberate?) Apple computers gained traction in music recording and graphic design, and gained a sort of bohemian chic that is rather impressive considering that it is essentially “Big Business” and, like most companies, designed to make money.

Clever partnerships, and particularly the inspired partnership with Adobe (think Acrobat PDF’s, think PhotoShop) strengthened their position with journalists, publishers and illustrators establishing the Mac as the creative profession’s computer of choice.

This turned out to be a good thing, as the naughties have been the most art friendly decade yet, as popular culture has come to resent things like ‘work’ and ‘industry’, and a certain sections of society have come to view activities like sport as trivial and meaningless when compared to the value and depth in culture, poetry, good food, yoga, spiritualism and so on.

In other words, the artists have moved up in the world.

Some of the more switched on folk will realise that brands like Gucci/Armani/Christian Dior or Ferrari/Porche/Aston Martin  or Rolex/Michel Herbelin/Patek Philippe are based entirely on massaging the egos of their customers, and in the last case, they probably don’t even keep better time than a black plastic Casio.

But not many of the arty crowd have realised that Apple is using their independent nature against them. The Mac user seems to be infected with the idea that in using a Mac they are somehow being beneficent to the world, will somehow be more creative, they they are part of some loving brotherhood that has exclusive access to the truth and the light.

This is because, by accident or design, the Apple brand has been developed to find that part of our mind that wants to believe and wants to belong, and is easily dazzled; the brand is acting like a religion.

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Apple’s alliance with artists continues with U2 and the Black Eyes Peas, both highly credible symbols of free-thinking modernism. But I want you to ask yourself: what is free thinking about this computer company? I’m not sure, but I suspect the only free-thinking thing about Apple is its association with icons of the free-thinking world. It is just an electronics company for Pete’s sake. Like Sony, like Samsung, like Nokia.

If you believe there is any more to it than that, then you are welcome to pay for it.

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PS: Besides the defunct G4 in the drawer, there is also an iPod classic in my home. I like it. I like to hold it. Mmm.





Family Tree Nonsense

18 10 2009

For many, learning about their family tree can be a real joy and pleasure.

Realising that a long distant grandfather was in the guild of barber-surgeons, or that you have a criminal or judge or, heaven forfend, someone famous in your lineage, can be a real thrill, and provide you with significant ego-boost, or perhaps a nice feeling of belonging.

The reason why it’s so often a positive experience, is due to an interesting mathematical oversight.

What do I mean?

This fractal can teach us something about ancestry: we have more ancestors than we tend to suppose...

This fractal can teach us something about ancestry: we have more ancestors than we tend to suppose...

I mean that people can read anything they want from a family tree, and this is made easy by the exponential nature of ancestry.

Would you find it remarkable for someone to say they were directly descended from Isaac Newton, Henry VIII or even Jesus? Would you think more of them?

What about people who say they are ‘from’ somewhere? – “my family originally come from Brittany…”, or “my family fought in the  revolutionary war…”

Analysis…

Now anyone who knows about the maths of ancestry, knows that there is actually very little remarkable about relations with famous people, especially from a long time back. If you have two parents and four grandparents, eight great-grand parents and so on, you can guess the numbers get big quite quickly.

The American revolutionary war was around 230 years ago, so perhaps eight or nine generations[1].  Nine generations back we had perhaps 2^9 (or 512) ancestors, and their folks were probably still around you can add them to the mix (another 1024)  giving over 1500 relatives, all swanning about somewhere in the world around the time of the war.

OK, you might want to reduce the number a bit due to some folks appearing  multiple times in your tree; (yes, in-breeding happens to all of us), but the number is probably still well in excess of  a thousand.

So, with over a thousand ancestors around at the time, the chance of having at least one involved in the war is pretty darn good (especially if you are were born to US citizens). I would argue that for anyone who can trace back three generations (to your eight great-grandparents) in the US, it would be far more remarkable if they didn’t have ancestors that fought in the war.

As you get further back in time, the numbers get more serious. A thousand years back , or forty generations, the straight maths gives 1 099 511 627 776 ancestors. Of course, this is impossible, as there were not enough people in the gene pool; the real number is clearly much lower and this is due to our old friend, in-breeding – where the family tree morphs into more of a family ‘web’ and involves the majority of the (breeding) population of your “gene pool”, the group that share enough in-breeding to behave somewhat like a super-organism. Where cross flow of genes between parts of the pool becomes retarded, (most usually by geographic barriers) the pool may divide and racial difference may develop.

Of course, we live in a time of great ‘connectivity’, and the US is a great example or a melting pot, with a very ‘open’ gene pool. This means that statistically, the chance that all 1000+ of one’s ancestors were around in the revolutionary war is hopelessly optimistic (unless there were special circumstances, like a closed community with a high degree of in-breeding, as may be the case with some religious groups).

So basically, anyone who says their family is all-American, “since the revolution” is being highly selective in their analysis.

Of course, western society does tend to invest much importance in the male line – which is far more specific – and would only give a couple of  chaps alive in ~1780, and if you can indeed prove this then the claim may be considered more interesting.

However, the argument that the male line is more important in some way (such as in the forming of character, or of any particular heritable trait) is pretty unconvincing. So even if you can trace a direct male line to Isaac Newton, this is no guarantee that you will pass your physics tests! Any advantages he had, will have been diluted by the 16,000 or so other folks who contributed just as many genes.

The male and  female lines can actually be traced (using mitochondrial DNA for the female line and Y-chromosomal DNA for the male line), but though this makes it easier to trace these ancestors,  it is perhaps still unwise to assume this line is more important than the thousands of other ancestors.

In the case of the USA, there is another factor, the large family sizes, and the resulting high population growth rate. The population present during the revolution have, by all accounts, been very fruitful. That means that even if you could trace your male line right back to, say, Thomas Jefferson, the chances are, you are not unique.

The Opinion Bit…

Hard-earned privilege...
Hard-earned privilege…

I am constantly annoyed by selective analysis of ancestry. I hope that the above simple illustrations alert the reader to this trickery, or at least confirm the reader’s suspicions (or convictions) that much of this is wishful thinking. What is most important to our own ‘value’ in the world is surely what we ourselves decide to do, not what our remote ancestors may have done.

However, I cannot deny that family research is still hugely interesting, even if what it really confirms is that we are all brothers and sisters, and none of us is superior due to our ancestry.

Don’t even get me started on so-called “royalty”!

[1] How long is a generation? http://www.ancestry.com/learn/library/article.aspx?article=11152





The speed of evolution

22 10 2008

The theory of evolution is greater than it looks. It is not just clever. It is not just useful. Its biggest value is as a nail in the coffin of some very destructive ideas. Not just the idea that Europeans are superior to Africans, or the idea that humans are superior to animals, but the idea that we all have some divine purpose – and therewith, the whole idea of good and evil.

The fascinating story of how the the tide of evidence has led to the unravelling of religious explanations for the world is, however, not what I wish to ponder here. No, I would like to ponder an area of evolutionary theory that still holds some uncertainty, some mystery.

Relax, I am not trying to ‘break’ or disprove evolution. I am fairly confident it it largely right, but I still think there are questions about it speed.

The problem…

Anyone who has read on the subject understands the pure cunning of natural selection. Basically put, any replicating ‘creature’, that produces slight mutations in its offspring, will produce some offspring that are better than itself – better at competing for resource, better at surviving. Of course many mutations (indeed perhaps most mutations) may produce ‘worse’ offspring, but if the better offspring survive proportionally more, there will be a generational improvement.

This is the same phenomena that allows us to breed better race-horses, beef-cattle or strawberries.

Now, we can see the effects of selection very quickly in a petri dish of bugs, or perhaps in viruses in the human population, but the evolution of large mammals is a slow affair, not easily observed, and it took the discovery of ‘missing links’ to confirm the theory that we had indeed evolved from primate stock.

I personally have not read widely on evolution, I have simply spent lots of time thinking about it, and also spent some brain cells on pedantic calculations and computer simulations.

What comes up, again and again in the simulations is the question of speed.

Speed?

Yes, speed. How fast do we evolve, and have we had enough time to do it?

Aside…

There are two ways to tackle the question of evolutionary speed. One the one hand, you could say: we have only had, say, 5 billion years, to evolve from the basic elements, so we must have evolved fast enough. The calculations must simply be made to fit the data.

Some (not me) have however said, hang on, calculations show that we haven’t had the time to evolve, so the theory must have some massive fault.

The latter argument betrays a misunderstanding of evolution. They assume that as evolutionists claim evolution is ‘true’ and ‘right’, that their models must be right. But if their models suggest we needed 100 billion years to evolve that will prove that evolution is too slow and some other agency is required to square the circle.

However, just because evolution is fairly certain to be right, that doesn’t mean the models are simple, and I hope to give some insight into the challenge that I came across in my own amatuer attempts at the challenge.

Factors that throttle evolutionary change… 

Let’s look at the things that effect the speed of evolution.

  1. the generation gap (time between generations)
  2. the strength of the mutation.
  3. the selection pressures (multiple)
  4. the male/female requirement (and its surprising turbo function)

The first one is obvious – the more generations you get through each year/millennium, the greater potential for evolutionary change.

Mutation strength is more interesting. You could have multiple errors in a DNA sequence, the more errors the stronger the mutation. However, some errors in the DNA may have no particular effect, while other errors could be catastrophic, so that matters too. To keep things simple, lets just focus on the ‘strength’ of the inter-generational change.

If the mutations were very small and subtle, this, I would predict, would slow evolution down. However, if the mutations are too large (remember they are random), they are less likely ‘to be compatible with life’. However, I suspect because they are random, they will come in all shapes and sizes, ranging from untraceably small – to very fatal (resulting in early miscarriage).

However, we have seen in the fossil record evidence that evolution speeds up and slows down. The statistics of mutation ought not to change like that, so there must be more to it.

Selection pressure is the next, and even more interesting, factor.

People have questioned why the world doesn’t have living examples of ‘the missing link’. They must have been ‘viable’ in their own right, so why didn’t they survive?

Some thought on the subject (as well as my own simulations) show that this is not surprising. The speciation event (when one species splits into two) is usually the result of a population becoming subjected to a varying selection pressure (usually geographical). If the population is well mixed, its keeps together, but a mountain range or body or water can reduce the interaction enough to allow the different ‘random walks’ to optimise the two populations for their environments. Allowed to proceed for any length of time, you land up with two separate species, with nothing between. Once separated, they cannot ‘rejoin’ even if they mix once more, so the divergence will continue. Some have argued that ‘spurts’ in evolution augment this speciation process.

So why do these spurts happen? This is most likely selection pressure, but how does it work? Well, putting it simply, the more the environment changes, the more the creatures will need to change to survive. In a static environment, creatures will evolve to suit, but following the law of diminishing returns, once happy, would have no driving force to change any more.

However, you could well argue, that while a quickly changing environment allows faster evolution, it is simply taking its foot off the brake, something else is really controlling the maximum speed of evolution.

What do I mean by maximum speed? Well ask how fast would an environment need to change, such that evolution could not keep up – then you have reached its maximum speed.

There is an example that some folks think is an example of an environment that promoted fast evolution. Theorists have suggested that early man was often the victim of famine, and often needed to move around, which resulted in accelerated evolution. The stronger penalty on the weak, the higher reward for strength and wisdom, meant that potentially positive mutations, that may be lost in stable ‘easy’ environments, were more effective in this environment, thus accelerating change.

There is much written about selection, by people much smarter than myself, so I will not elaborate any more on it. I would simply summarise, that in the course of billions of years, some environments would allow fast evolution, while others would stagnate, and the average speed, while hard to quantify, would not be consistently high enough to be the key to the sort of evolutionary speed we need to gain so many evolved features is so few generations.

So at this stage, I would like to point out the most marvellous thing about evolution, which I think can multiply the effects of natural selection.

The two-sex system and its accelerating effect…

As I grew up, I sometimes wondered why we needed two sexes. Why not just allow all creatures to have offspring, add in a little mutation, and hey presto, it should work. 

This was the form of my very first simulations (some 17 years ago now!). It showed me fairly rapid evolution and increasing fitness, so all looked good. If you set the bifurcation ratio to 2, give each child a random ‘fitness’ and then set the chance of reproduction be proportional to fitness (a very simple algorithm), the population did get fitter. However, when I compared it with the standard model, where you have two sexes, two differences in macro behaviour showed up.

Firstly, you have to add an extra ‘selection’ criteria. It is not just about surviving to reproductive age, it is now about surviving AND finding a mate. And you can forget about monogamy, so a very fit (for sexual selection) male could fertilise several females, at the expense of less fit males. This effect can (in my model) greatly accelerate change. All you need to do to get fast change, is ensure that partners can identify fitness accurately. 

The second interesting effect from having two sexes (and what I found out from my model), is that good genes can spread through the population, which does not happen in the one-sex model. This spread of good genes means that one part of a population could be learning how to deal with sunburn, while another is learning to deal with sickle-cell anemia, and their solutions can be shared by all.

Now we are talking. This, if I have my thinking right, would be a serious turbo-boost for evolution, allowing it to evolve lots of traits in parallel, whereas the single sex model would have to work on one feature at a time – first build an eye, then build a digestion tract, then build a good sense of humour… This buys evolution a lot of time. This makes it far more likely that 5 billion years is enough time to make all the amazing variety we see today.

So I would therefore argue that this makes it more likely we had time to go from the first two-sex replicator to the world of wasps, earwigs and herpes.

That begs my next question: how did the first two-sex replicator come about? I think the computer modelling may be beyond me, but I hold out hope for my children!