Tagged: review

“If you wanted to make a flying animal, you wouldn’t start with a hippo”

“We used to think our fate was in the stars. Now we know in large measure our fate is in our genes”   

-James Watson

Beholding the variations among each organism, triggers us to raise a question about what made them different from each other? And surprisingly, we have the answer – Evolution. Though, we also know that the basis for the intricate phenomena of evolution are DNA, mutation and natural selection which ultimately aids in understanding the gradual sequential ‘change’ from the most primitive form to the complex one. But for us, the actual mechanism of how they occur in nature is still a matter of curiosity. Therefore, we often prefer simple artistic way to quench our curiosity about this gradual upgrading amongst the organisms. Our pursuit, of knowing the actuality, has been simplified by Richard Dawkins. The metaphorical title of the book- Climbing Mount Improbable by Richard Dawkins not just only tempts its readers to read but also makes them to think in an evolutionary angle. Fortunately, I am one of them to be wooed by his graceful way of writing that unleashes the complexity into the simpler form. Being one of the World’s leading evolutionary biologists- Richard Dawkins, in this book, writes elegantly to define how evolution works under natural selection based on the gene-centered axis.

Professor Richard Dawkins, a British ethologist; an evolutionary biologist and on the top, an eminent writer, was born in Nairobi in 1941. He was an emeritus fellow of New College, Oxford University and got his doctorate under Novel Prize winning ethologist Niko Tinbergen. As mentioned in this book, he is a ‘dyed-in-the-wool Darwinist’ who supports Darwinism. He works immensely to support scientific education, critical thinking and evidence-based understanding of the natural world in the pursuit to conquer the narrowness of religious fundamentalism, superstition, intolerance and suffering.  Dawkins wrote many fantastic books to support the gene-centered view of evolution. Some of his collection includes The Selfish Gene (1976), The Extended Phenotype (1982), The Blind Watchmaker (1986), River out of Eden (1995), Climbing Mount Improbable (1996),Unweaving the Rainbow (1998), A Devil’s Chaplain (2003), The Ancestor’s Tale (2004),The God Delusion (2006). With his 1976 book The Selfish Gene, Dawkins came into eminence. This book popularized the gene-centered view of evolution and coined the term meme. With the aid of all his publications, he introduced the influential concepts into evolutionary biology; the concept of evolutionary gradualism, the concept of “all life evolves by the differential survival of replicating entities” and some astonishing concepts like- The Extended Phenotype and the non-existence of supernatural creator (The God Delusion). Being an atheist and humanist, he is renowned for his criticism of creationism and firmly believes in ‘genes gives rise to genes’.

Climbing Mount Improbable, like many of his books, follows the similar trend of broadening the horizon for an evolutionary explanation significantly based on the idea of natural selection with the gene-level perspective. The creative uses of metaphors, oxymoron and litotes have made this book- worth reading in the literary context. Ten different chapters, metaphorically entitled, describe in their best, for how to climb Mount Improbable. The vibrant examples define, vividly, what Mount Improbable stands for.

Climbing up the terrain from Facing Mount Rushmore, one can easily make out the concept of ‘nature selects the best of all’. Dawkins beautifully defines that before we start hiking up on Mount Improbable, it is essential to know that the resemblances are accidents, that the design object can be designed but the designoid objects which looks as if they were designed, are due to non accidental-cum-non-random cumulative process. True designs and designoid pseudo-design objects forms a chasm between chance and non-randomness. Some living organisms converged into the similar shape, of some usefulness, though they might not be mimicking each other, here comes the idea of Convergent Evolution. Beside the “nature-selects” concepts, Dawkins pops in the concept of Artificial Selection by a human chooser through computer-based program called Biomorphs. Though it worked, but still, they lacked the real world scenario of Prey-predator interactions and many other environmental factors that limits the survival.

The Silken Fetter artistically showed, by the help of the spider web, that the natural selection selects the best and many species of spiders have their own distinctive way of improving themselves to get the best survival strategy for catching the prey and minimizing the cost of weaving a web. The illustration, that impressed me, was of the independent evolution of Ladder webs in Spiders from New Guinea and Columbia. To understand the natural selection through artificial spider behavior under the influence of numbers in computer’s memory, so-called “genes”- NetSpinner I, NetSpinner II (asexually reproduced) and NetSpinner III (sexually reproduced) were used. The oxymoronic Artificial Natural Selection helped to understand how population evolves; generation after generation with further refinement even in artificial environment let-alone the natural circumstance.

The most significant chapter of this book- The Message from the Mountain-not just helps in justifying the use of title Climbing Mount Improbable but also holds the center theme of the entire book, whilst the rest of the chapters provides the strong circumstantial evidence to prove it. Generally, Darwinism was thought to be the theory of random chance. Dawkins clarifies the misconception-“It is actually the theory of random mutation plus non-random cumulative natural selection”. It’s all about the step-by-step progression from primitiveness to the complexity, a journey up from the foothills to the paramount. An organism, at the bottom of this Mount, will reach to the top by the gradual perfection due to random mutation and non-random selection. Example of Spreading Bush fire helps in understanding the role of heredity- hence DNA as the accumulated wisdom of the ancestors. Mount Improbable got its name –Improbable, because whoever is climbing the mount must know that- ‘there can be no sudden leap’ i.e. the complexity increases step-by-step, but not all of sudden; ‘there can be no going downhill’ i.e. no organisms can return to its primitive form and the best part of this Mountain is ‘there may be more than one peak’- i.e. like in spider webs, one species have many ways of acquiring the refinement. The best line in this chapter is:

“No animal ever made a living purely by being on the evolutionary path to something better. Animals make a living by eating, avoiding being eaten and reproducing” (P.83)

This addresses Pre-adaptation- where an organ of some function can be used for another function, on our way towards the top of Mount. Species on their way, sometimes, are surprised by the Macro-mutation or Saltation which makes them completely different from what they were and hence forming a new peak. Richard Goldschmidt, hence, called it as the “hopeful Monster’ theory”.

The title Climbing Mount Improbable best fits to explain the vivacity of the book – the complicated gradual evolutionary path, with the strict rules of no sudden leaps and no going down provided with the alternative way or peaks and hence justifies itself to be the best metaphorical title.

By now, we discern that the gradual refinements or improvements are needed, to be in the summit. Improvements or progressions in flight, sight, spirals and symmetry shows how genes keeps on mutating randomly to produce the best design and how these are non-randomly selected by the nature. Dawkins sprinkles some hilarity- “If you wanted to make a flying animal, you wouldn’t start with a hippo” (P.101) – to prove that many peaks exists with their own height of ‘fitness’ and that they can’t be clumped together. It’s flabbergasting to know how species developed their wings. What there was before?  The gradual evolution developed the feathers from scales. In nutshell, the best amongst all organisms are selected for their flying, gliding, jumping and swimming behavior coded in their genes.

Coming to the sight refinement, this is the chapter I liked the most- The Forty-fold Path to Enlightenment. The title itself gives us enlightenment! And marvels us with the fine splash of delight, as we keep on hiking high, we will see how eyes evolves from- a photocell, the layers of photocells, the layers bent inward, the pigment cup-shaped eye, the pinhole, the magic window-lens, then the vitreous mass and finally, we got our precious Eyes to behold the most beautiful World around us from the summit of Mount Improbable. Beside these fine-gradual slopes that leads to top, what lured me in this chapter is – “Loudspeaker as a ‘Silence-device’ of a radio”, where Dawkins flawlessly mention about the eyeless gene in Drosophila that actually makes eyes and small eye genes that makes the bigger eyes! That any mutational damage to these genes may act in counter way. Eyes developed forty times independently to give us many peaks of enlightenment – includes all those superposed, neural superposed, apposed, intermediate- Compound and Camera type eyes. Isn’t this so incredible?

Selection pressure helps in shaping the slopes and creating some impassable cliffs. All that matter is variation- a genetic one. Lack of variation, sometime, limits Evolution. The Museum of all shells shows the existence of some impassable cliffs. Natural selection, hence, needs an alternative to choose and genetic variation to work on. If there is no variation at all, but only the environmental factors, no evolutionary event will occur and so Mount Improbable will have no slope to cling on. Here Dawkins introduced ‘Blind Snail Maker’ computer-based selection.

‘The evolution of evolvability’- is the main theme of Kaleidoscopic Embryos. Some embryos make themselves good enough to be evolved further. Visual beauty of embryo provided with symmetry can oppose restriction and here mutation acts as a mirror. With gorgeous examples of Radiolaria and other echinoderms species, the amazing symmetries and segmentation within all organisms, hence showed the gene-to-organism mapping. The processes of random mutation and selection produces far better ‘likenesses’. He uses ‘Arthromorphs’ to make us clear about duplication-deletion process of mutation artificially and to produce best fit kaleidoscopic genes.

In last two chapters, Pollen Grains and Magic Bullets and The Robot Repeater, Dawkins talks about “for a benefit of” idea. All organisms are there cause of DNA and its replication. Like computer virus and Robot, DNA is assigned with a command of “Copy me and spread me around” in circular fashion. All it emphasizes on: is Genetic Variation and spreading of genetic information.

‘A Garden Inclosed’ strikingly presents the life of Fig wasps and Fig tree. It’s marvelous to observe how two different species on their way up the summit, can co-evolved following the stable balance theory. Unlike in evolution, where winners are selected, there exists an exception – Altruism- due to Kinship- which forces selfish genes to move ahead.

Thus, the whole book ends giving us a clear insight of how evolution occurs through ‘non-random’ natural selection which depends on variations (random mutation and recombination), individual or inclusive fitness and heritability. The Mount Improbable- ‘Evolutionary high ground’ can’t be climbed hastily. A gradual climb will lead us to the summit but we are not allowed to quit.

There are merely few flaws that can be pointed out in this book and that’s the only point I disliked and perplexed me. As he mentioned “Nowadays, the replicator that matters on Earth are the DNA molecules, but the original replicator probably was not DNA” (P.261) what was it then, if it was not a DNA?

Though Dawkins talk about the evolution of most of the species belonging to all phyla of both kingdoms, he didn’t mention about the primitive plants or animals (he mentioned some planktons in Kaleidoscopic Embryos). By primitive, I mean prokaryotes. Prokaryotes may have given rise to Eukaryotes? It would have been best, if Dawkins have mentioned about them. May be the prokaryotes were on the periphery of foothills of Mount Improbable, so remained unnoticed.

It is essential for us to think whether Darwinism and creationism are compatible? For me, both of them are strictly incompatible. Since we know, Darwinism is purely a theory of non-random chance and relies on Evolution where each primitive organism develops into the complex form gradually with purposeless process like mutation and best of them are selected to move further. While Creationism trusts in a Creator and have broad sense of God has created the world with purpose. If God had created the World, as per Genesis, the Mount Improbable wouldn’t have been “The Improbable”. No variations would have existed. But, we can now easily prove that each organism varies because of their genes. Fossils evidences and Carbon-dating mechanisms have proved the non-existence of supernatural designer and have supported Darwinism. All organisms that exist today are the refined species of the past. Whilst Creationists ideas wholly depend on the beliefs and myths, they lack the scientific basis.  Science (that relies on facts) and religion (that depends on beliefs) are, hence, incompatible.

To support Darwinism, one must be able to prove that Evolution is true. As Dobzhansky stated “Nothing in biology makes sense except in the light of evolution”. Generally, Evolution is a gradual change in an organism with respect to time while technically; it’s a change in the frequencies of genes or a gradual process where some sudden modification (Saltation) may give rise to a new species or organ. We have sufficient examples to show that evolution is true and it does occurred. Phylogenic studies can help us in tracking the ancestors of a species based on genetic information. We gradually climbed the Mount from Pre-biotic (Primordial) Soup to algae to slime moulds to slugs to reptiles to mammals and so on. The basis lies on DNA. The variation through mutation (Duplication and deletion or recombination) gives rise to various forms which are hence inherited generations after generation. Evolution act as a ‘Tinkerer’ (as said by Francois Jacob) who build or modify the stuffs which already exists around. Best example of proving that the evolution is true is the sequential development of eyes, brains and wings from the primitive forms.  Use of computer based software (Biomorphs, Arthromorphs etc) can also aid.

Last but not the least, we are at some crest, that we still have many slopes to crawl on and to reach to the zenith of Mount Improbable.

[ Apology for ‘this’ long post. One must read this book (Climbing Mount Improbable) to understand the enigma of evolution]

Photocredits: Internet

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Variation

“TIME OUT!!!”

No, this isn’t a basketball game we were attending, but rather a desperate attempt by a clueless group discussion leader to bring a house to order. Little short of a parliamentary session, if you’d like an Indian analogy.

There was much variation in opinion within the group Friday last when we were discussing the second chapter of “The Origin of Species”, the larger group slowly diversifying into sub-groups and sub-sub-groups, with much confused looks on faces. Let me try and explain some of this confusion..

The second chapter “Variation under Nature” is where Darwin uses the classification of life (the Linnaean classification system) as

Darwin’s Shells Image from http://www.guardian.co.uk

a means to describe his theory of the origin of species, in a very brief way. The presence of “varieties” within a group of organisms was the baseline for the origin of “a new and distinct species” by “Divergence of Character”, was Darwin’s argument. Now here was where the confusion began… what did he mean by a “variety”?

In chapter one Darwin uses the terms “species” and “variety” without defining the terms (yes, I know, we researchers are hung up on definitions) leaving a lot of room for assumption. In the second chapter, he goes into great detail on the distinction between species and variety, and tries his best in defining what he means by a variety. I say tries his best because we were still confused even after all that discussion around the subject,  leading to confusion number one. The confusion wasn’t limited to us though.. Darwin also surmises that taxonomists (of his day) are a confused bunch over the topic, not being able to decide how much of a difference is necessary to distinguish variety from a species. However, he does mention his own definition of a variety as a form the characteristics of which “…. can be inherited for at least some few generations.“. This is an important point that he brings forth in the discussion, that of inheritance, which is, of course, a repeated theme in the book, but gets first mention here. It also got us thinking about whether he was alluding to epigenetics, and if he meant that forms otherwise just exhibited phenotypic plasticity. That got us arguing for at least a half-hour. We were just in the first para, by the way.

chapter2 2nd

Variety

On to confusion number two, and a jump to the concluding para of the chapter (as you can see, we were an organised bunch). Darwin talks about genera, how large genera have the most variation, and “larger genera thus tend to become larger”. But then he also says that “larger genera also tend to break up into smaller genera”. Now, pray tell, if this does happen, how do the large genera remain large?!

The gist of the chapter seemed to clear, but his justifications need more reading into, perhaps. We’ll be continuing with the confusions, sorry, discussion, this Wednesday, the 6th of February at 5.30 pm in the Tea Room. Do join us to add to the confusion. 🙂

Chapter 3 will be discussed most probably, on Wednesday next week on February 20th.

Origin of domestic races

Charles_Darwin_by_G._Richmond 1830's

Charles Darwin in 1830’s after the expedition by G. Richmond

Year 1831. 27th December. H.M.S. Beagle set on an epic expedition to survey Patagonia and other parts of the Neotropical coast. The captain of the ship, Fitzroy, would have never even dreamt that the journey is going to rewrite the history of life on Earth. Nor would he have realized that a young guy, who shared a cabin with him, will be the reason behind this. No marks for guessing who it was: Mr. Charles Darwin, my second hero (had given the first place to Mr. Wallace a long while ago!). The idea that of the origin of species, has its origin traced back to his five-year long journey (Are you listening?! Bloody five years, braving the odds of sea and uncharted landscapes. Imagine five long years of field work for your PhD. I wouldn’t have seen the end). That spark generated in him, generated a fire that burnt in him for almost twenty long years before culminating in a book, “the book” that shook the world. That’s 24 years after that expedition. In Darwin’s view an abstract. Hmm…what took him so long? More than that, what is that he wrote demands an understanding among students like us, separated in time by almost 150 years. Thanks to our ESS secretaries for deciding to explore this. The first meeting happened last Thursday. Target: The Introduction and Chapter 1.

I can summarise Darwin’s introduction based on three aspects.

  1. Darwin’s emphasis on the role of biogeography towards his insights,
  2. The controversy behind Wallace and Darwin and
  3. Influence of “vestiges of creation” on him.
200px-Charles_Darwin_aged_51 Maull and Fox 1859

Charles Darwin during the publication of Origin of species by Maull and Fox 1859

 As a student of biogeography, the first statement from Darwin’s Origin that remained etched in my mindscape is this one by him in the opening paragraph:

When on board H.M.S. ‘Beagle,’ as naturalist, I was much struck with certain facts in the distribution of the inhabitants of South America, and in the geological relations of the present to the past inhabitants of that continent. These facts seemed to me to throw some light on the origin of species—that mystery of mysteries.” Darwin, 1859.

It was astronomer Sir John Herschel, in a letter to Charles Lyell in 1836, who had referred to the origin of species as the “mystery of mysteries” (Costa, 2009).

The controversy behind Wallace’s influence on Darwin seems to have been resolved (watch the appended video). In the introduction, Darwin explicitly acknowledges that he was “induced” to write by Wallace’s research paper send to him from Malay archipelago.

The third thing that Darwin mentions is this work by Robert Chamber “vestiges of creation”. Costa (2009) explains Chambers view as saltational vs. gradualism as espoused by Darwin. Chapter one was his attempt to prove this point and provide an exhaustive evidence for variation under domestication.

20130125-115148.jpg

Domesticated?

We, a bunch of nine, discussed for an hour on this chapter. Borrowing from Darwin, I would like to call this chapter the “Origin of domestic races”.

Darwin goes to stunning details on variation under domestication borrowing examples from plants to pigeons. Why take so much pain? It was his attempt to get across the message that domestic races share a genealogical relationship, an end product of human mediated accumulative selection that is artificial selection (Costa 2009). To cite Reznick (2010) “This opening chapter presents the raw material that Darwin needs for his subsequent arguments about natural selection to work. The changeability of organisms under artificial selection proves that the availability of heritable variation and amount of change that is possible are easily sufficient to account for the diversity of living things that are present in the world today, given the age of the earth and the vast amount of time that has been available for natural selection to act.

One last point, keep at the back of your mind the distinction between natural selection and speciation. Researchers including Ernst Mayr and recently, Jerry Coyne have argued that Darwin’s origin of species doesn’t quite address the issue of speciation. Let’s deduce it for ourself first hand if that’s the case!

Rupees 1,27,41831.28 check

Rupees 1,27,41831.28 check

Meet you all next Wednesday 5:30 pm Friday 5.45 pm in either the Lotka Volterra lab or the Class room. I will post all the soft copies of references to ESS. Pick it up from them.

References:

  1. Charles Darwin, 1859, On the origin of species by means of natural selection or the preservation of the favoured races in the struggle for life. John Murray.
  2. James T. Costa, 2009, The Annotated Origin. Facsimile of the first edition on the origin of species.
  3. David N. Reznick, 2010, “The “Origin” Then and Now: An Interpretive Guide to the “Origin of Species”, Princeton University.

Books on my list

23bDiamond.jpgI first heard of Jared Diamond a few years back, when a summer student at the lab I was interning in, happened to mention him. The discussion was about Ethiopian success in the Olympics, especially in athletics. From there, the conversation moved to traits associated with hunter-gatherers versus agriculturists, and that’s when Guns, germs and steel was quoted. I was ignorant of the book and Diamond at that point, which was embarrassing for two reasons. Not only is Diamond a well-known biologist and popular science writer, but also because the conversation was with an undergraduate engineering student.

Jared Diamond’s work has crossed paths with me several times since then. In the General Biology class, with Prof. Gadagkar during introductions in the Animal Behaviour class (when I could smugly say I was reading the book), Kartik’s course on Community Ecology and in Hari’s introduction to his Ph.D. work (where he mentions Diamond’s work with birds in Papua New Guinea). Three years since I first heard of it, I’m still trying to finish it (I blame it on the small print) but I’m sure I will someday. When I do, I’d probably follow it up with the book on the left . Here’s why one might want to skip it, and here’s why one wouldn’t.your inner fish

For the Animal Behaviour book assignment, I was handed A fish caught in time. The Search for the Coelacath by Samantha Weinberg. It is a very exciting story starting from the mystery surrounding the first fish which walked on land, to finding living populations of its predecessor in African and Indonesian waters. The human characters in coelacanth’s history show rich contrasts as well, from unyielding adventurers to ruthless scientists. Primed after reading this book, I got really excited about the Tiktaalik discovery back in 2006. The author of the second book on my list is one of the paleontologists who discovered the Tiktaalik fossil. Here is why one might read his book, Your inner fish.

2012 in review

WordPress.com in all its glory prepared a 2012 annual report for our site. Here are the excerpts –

We got 4700 views in 6 months! And (weirdly) from 33 different countries. We had 10 posts written by 7 authors, which is excellent keeping in mind the fact that we only started writing in November.

There are almost 500 photographs now on this website, thanks to the photo gallery (which by the way got almost 2000 views in one day, i.e. yesterday!).

Click here to see the complete report.