It is a must read for all scholars and students interested in the evolutionary biology of reproduction.
This classic work on the rules of sex -- updated for a new generation -- is still as provocative as the day it was published, providing simple explanations for any and all questions about what happens in the bedroom. Sex isn't as complicated as we make it. In Sperm Wars, evolutionary biologist Robin Baker argues that every question about human sexuality can be explained by one simple thing: sperm warfare.
In the interest of promoting competition between sperm to fertilize the same egg, evolution has built men to conquer and monopolize women while women are built to seek the best genetic input on offer from potential sexual partners. Baker reveals, through a series of provocative fictional scene, the far-reaching implications of sperm competition.
From infidelity, to homosexuality, to the female orgasm, Sperm Wars turns on every light in the bedroom. Now with new material reflecting the latest research on sperm warfare, this milestone of popular science will still surprise, entertain, and even shock. The extraordinary role of viruses in evolution and how this is revolutionising biology and medicine. At its core, The Power of Habit contains an exhilarating argument: The key to exercising regularly, losing weight, being more productive, and achieving success is understanding how habits work.
As Duhigg shows, by harnessing this new science, we can transform our businesses, our communities, and our lives. The Power of Habit is an exception. Charles Duhigg not only explains how habits are formed but how to kick bad ones and hang on to the good. Skip to content. The Selfish Gene. The Selfish Gene Book Review:. Books do Furnish a Life.
Books do Furnish a Life Book Review:. The Revolutionary Phenotype The amazing story of how life begins and how it ends.
Author : J. Why Evolution is True. Author : Jerry A. Why Evolution is True Book Review:. The Evolution of Cooperation. The Evolution of Cooperation Book Review:. Jeanne McDermott. Richard Monastersky. Dorion Sagan. The 'selfish gene' is one of the most controversial subjects in modern genetics, and one with a major bearing on the nature vs.
It allows you to have the essential ideas of a big book in less than 30 minutes. As you read this summary, you will discover that in nature, altruism does not exist. All living species are genetically selfish. You will also discover : that your genes have created you for their own survival; that your children will be naturally selfish, but that you have the means to change that through culture; that in terms of reproduction, the male is less involved than the female; that since the appearance of modern man, genetic evolution is no longer the only type of evolution in the world.
The selfish gene theory is another facet of Darwin's theory. Rather than focusing on the individual organism, it takes the point of view of genetics. Your genes survived in a world where competition was raging, so the predominant quality in a gene that thrived is certainly ruthless selfishness. A selfishness that inevitably affects individual behavior. But by understanding what your genes are tending towards - selfishness - you may have a chance to counteract them and achieve what no other species has ever achieved: becoming an altruistic individual.
Are you ready to regain control of your identity? Hamilton and others. The book provoked widespread and heated debate. Written in part as a response, The Extended Phenotype gave a deeper clarification of the central concept of the gene as the unit of selection; but it did much more besides. In it, Dawkins extended the gene's eye view to argue that the genes that sit within an organism have an influence that reaches out beyond the visible traits in that body - the phenotype - to the wider environment, which can include other individuals.
So, for instance, the genes of the beaver drive it to gather twigs to produce the substantial physical structure of a dam; and the genes of the cuckoo chick produce effects that manipulate the behaviour of the host bird, making it nurture the intruder as one of its own. This notion of the extended phenotype has proved to be highly influential in the way we understand evolution and the natural world.
It represents a key scientific contribution to evolutionary biology, and it continues to play an important role in research in the life sciences. The Extended Phenotype is a conceptually deep book that forms important reading for biologists and students.
But Dawkins' clear exposition is accessible to all who are prepared to put in a little effort. Oxford Landmark Science books are 'must-read' classics of modern science writing which have crystallized big ideas, and shaped the way we think. Covering all species from yeast to humans, this is the first book to tell the story of selfish genetic elements that act narrowly to advance their own replication at the expense of the larger organism.
Choose the important thing ideas inside the e book with this brief summary. Over 3. Molecular replicators are made from lengthy chains of smaller building-block molecules in the same manner that a phrase is made up of a string of letters.
The primary replicator routinely had a competitive edge over all the different molecules within the primordial soup because they could not replicate themselves, and subsequently the replicators have become more numerous than every other sort of molecule. Web icon An illustration of a computer application window Wayback Machine Texts icon An illustration of an open book.
Books Video icon An illustration of two cells of a film strip. Video Audio icon An illustration of an audio speaker. Audio Software icon An illustration of a 3. Yet in their fundamental chemistry they are rather uniform, and, in particular, the replicators that they bear, the genes, are basically the same kind of molecule in all of us — from bacteria to elephants.
We are all survival machines for the same kind of replicator — molecules called DNA — but there are many different ways of making a living in the world, and the replicators have built a vast range of machines to exploit them. A monkey is a machine that preserves genes up trees, a fish is a machine that preserves genes in the water; there is even a small worm that preserves genes in German beer mats.
DNA works in mysterious ways. For simplicity I have given the impression that modern genes, made of DNA, are much the same as the first replicators in the primeval soup. It does not matter for the argument, but this may not really be true. The original replicators may have been a related kind of molecule to DNA, or they may have been totally different. In the latter case we might say that their survival machines must have been seized at a later stage by DNA. Along these lines, A. Usurper or not, DNA is in undisputed charge today, unless, as I tentatively suggest in Chapter 11, a new seizure of power is now just beginning.
A DNA molecule is a long chain of building blocks, small molecules called nucleotides. Just as protein molecules are chains of amino acids, so DNA molecules are chains of nucleotides. A DNA molecule is too small to be seen, but its exact shape has been ingeniously worked out by indirect means. The nucleotide building blocks come in only four different kinds, whose names may be shortened to A, T, C, and G.
These are the same in all animals and plants. What differs is the order in which they are strung together. A G building block from a man is identical in every particular to a G building block from a snail. But the sequence of building blocks in a man is not only different from that in a snail. It is also different — though less so — from the sequence in every other man except in the special case of identical twins.
Our DNA lives inside our bodies. It is not concentrated in a particular part of the body, but is distributed among the cells. There are about a thousand million million cells making up an average human body, and, with some exceptions which we can ignore, every one of those cells contains a complete copy of that body's DNA.
It is as though, in every room of a gigantic building, there was a book-case containing the architect's plans for the entire building. The architect's plans run to 46 volumes in man — the number is different in other species. They are visible under a microscope as long threads, and the genes are strung out along them in order.
It is not easy, indeed it may not even be meaningful, to decide where one gene ends and the next one begins. Fortunately, as this chapter will show, this does not matter for our purposes.
I shall make use of the metaphor of the architect's plans, freely mixing the language of the metaphor with the language of the real thing. This metaphor will take us quite a long way.
The DNA instructions have been assembled by natural selection. DNA molecules do two important things. Firstly they replicate, that is to say they make copies of themselves. This has gone on non-stop ever since the beginning of life, and the DNA molecules are now very good at it indeed. As an adult, you consist of a thousand million million cells, but when you were first conceived you were just a single cell, endowed with one master copy of the architect's plans. This cell divided into two, and each of the two cells received its own copy of the plans.
At every division the DNA plans were faithfully copied, with scarcely any mistakes. It is one thing to speak of the duplication of DNA. But if the DNA is really a set of plans for building a body, how are the plans put into practice? How are they translated into the fabric of the body? This brings me to the second important thing DNA does. It indirectly supervises the manufacture of a different kind of molecule — protein.
The haemoglobin which was mentioned in the last chapter is just one example of the enormous range of protein molecules. The coded message of the DNA, written in the four-letter nucleotide alphabet, is translated in a simple mechanical way into another alphabet. This is the alphabet of amino acids which spells out protein molecules. Making proteins may seem a far cry from making a body, but it is the first small step in that direction.
Proteins not only constitute much of the physical fabric of the body; they also exert sensitive control over all the chemical processes inside the cell, selectively turning them on and off at precise times and in precise places. Exactly how this eventually leads to the development of a baby is a story which it will take decades, perhaps centuries, for embryologists to work out.
But it is a fact that it does. Genes do indirectly control the manufacture of bodies, and the influence is strictly one way: acquired characteristics are not inherited. No matter how much knowledge and wisdom you acquire during your life, not one jot will be passed on to your children by genetic means. Each new generation starts from scratch. Once upon a time, natural selection consisted of the differential survival of replicators floating free in the primeval soup.
Now, natural selection favours replicators that are good at building survival machines, genes that are skilled in the art of controlling embryonic development. In this, the replicators are no more conscious or purposeful than they ever were. The same old processes of automatic selection between rival molecules by reason of their longevity, fecundity, and copying-fidelity, still go on as blindly and as inevitably as they did in the far-off days.
Genes have no foresight. They do not plan ahead. Genes just are, some genes more so than others, and that is all there is to it. But the qualities that determine a gene's longevity and fecundity are not so simple as they were. Not by a long way. In recent years — the last six hundred million or so — the replicators have achieved notable triumphs of survival-machine technology such as the muscle, the heart, and the eye evolved several times independently.
Before that, they radically altered fundamental features of their way of life as replicators, which must be understood if we are to proceed with the argument. The first thing to grasp about a modern replicator is that it is highly gregarious.
A survival machine is a vehicle containing not just one gene but many thousands. The manufacture of a body is a cooperative venture of such intricacy that it is almost impossible to disentangle the contribution of one gene from that of another.
Some genes act as master genes controlling the operation of a cluster of other genes. In terms of the analogy, any given page of the plans makes reference to many different parts of the building; and each page makes sense only in terms of cross-references to numerous other pages. The answer is that for many purposes that is indeed quite a good idea. But if we look at things in another way, it does make sense too to think of the gene complex as being divided up into discrete replicators or genes.
This arises because of the phenomenon of sex. This means that any one individual body is just a temporary vehicle for a short-lived combination of genes. The combination of genes that is any one individual may be short-lived, but the genes themselves are potentially very long-lived.
Their paths constantly cross and recross down the generations. One gene maybe regarded as a unit that survives through a large number of successive individual bodies. This is the central argument that will be developed in this chapter. It is an argument that some of my most respected colleagues obstinately refuse to agree with, so you must forgive me if I seem to labour it!
First I must briefly explain the facts of sex. I said that the plans for building a human body are spelt out in 46 volumes. In fact this was an over-simplification. The truth is rather bizarre. The 46 chromosomes consist of 23 pairs of chromosomes. Call them Volume 1a and 1b, Volume 2a and Volume 2b etc. Of course the identifying numbers I use for volumes and, later, pages, are purely arbitrary. We receive each chromosome intact from one of our two parents, in whose testis or ovary it was assembled.
Volumes 1a, 2a, 3a,. Volumes 1b, 2b, 3b,. It is very difficult in practice, but in theory you could look with a microscope at the 46 chromosomes in any one of your cells, and pick out the 23 that came from your father and the 23 that came from your mother. The paired chromosomes do not spend all their lives physically in contact with each other, or even near each other. In the sense that each volume coming originally from the father can be regarded, page for page, as a direct alternative to one particular volume coming originally from the mother.
Sometimes the two alternative pages are identical, but in other cases, as in our example of eye colour, they differ. The answer varies. Sometimes one reading prevails over the other. A gene that is ignored in this way is called recessive. The opposite of a recessive gene is a dominant gene. A person has blue eyes only if both copies of the relevant page are unanimous in recommending blue eyes.
More usually when two alternative genes are not identical, the result is some kind of compromise — the body is built to an intermediate design or something completely different. When two genes, like the brown eye and the blue eye gene, are rivals for the same slot on a chromosome, they are called alleles of each other. For our purposes, the word allele is synonymous with rival.
Every Volume 13 must have a Page 6, but there are several possible Page 6s which could go in the binder between Page 5 and Page 7. Perhaps there are half a dozen alternative alleles sitting in the Page 6 position on the 13th chromosomes scattered around the population as a whole. Any given person only has two Volume 13 chromosomes. Therefore he can have a maximum of two alleles in the Page 6 slot.
He may, like a blue- eyed person, have two copies of the same allele, or he may have any two alleles chosen from the half dozen alternatives available in the population at large.
You cannot, of course, literally go and choose your genes from a pool of genes available to the whole population. At any given time all the genes are tied up inside individual survival machines. Our genes are doled out to us at conception, and there is nothing we can do about this.
This phrase is in fact a technical term used by geneticists. The gene pool is a worthwhile abstraction because sex mixes genes up, albeit in a carefully organized way. In particular, something like the detaching and interchanging of pages and wads of pages from loose-leaf binders really does go on, as we shall presently see. I have described the normal division of a cell into two new cells, each one receiving a complete copy of all 46 chromosomes.
This normal cell division is called mitosis. This occurs only in the production of the sex cells; the sperms or eggs. Sperms and eggs are unique among our cells in that, instead of containing 46 chromosomes, they contain only This is, of course, exactly half of 46 — convenient when they fuse in sexual fertilization to make a new individual! Meiosis is a special kind of cell division, taking place only in testicles and ovaries, in which a cell with the full double set of 46 chromosomes divides to form sex cells with the single set of 23 all the time using the human numbers for illustration.
A sperm, with its 23 chromosomes, is made by the meiotic division of one of the ordinary chromosome cells in the testicle. Which 23 are put into any given sperm cell? It is clearly important that a sperm should not get just any old 23 chromosomes: it mustn't end up with two copies of Volume 13 and none of Volume It would theoretically be possible for an individual to endow one of his sperms with chromosomes which came, say, entirely from his mother; that is Volume 1b, 2b, 3b,.
In this unlikely event, a child conceived by the sperm would inherit half her genes from her paternal grandmother, and none from her paternal grandfather. The truth is rather more complex. Remember that the volumes chromosomes are to be thought of as loose-leaf binders. What happens is that, during the manufacture of the sperm, single pages, or rather multi-page chunks, are detached and swapped with the corresponding chunks from the alternative volume.
So, one particular sperm cell might make up its Volume 1 by taking the first 65 pages from Volume 1a, and pages 66 to the end from Volume 1b. This sperm cell's other 22 volumes would be made up in a similar way. Therefore every sperm cell made by an individual is unique, even though all his sperms assembled their 23 chromosomes from bits of the same set of 46 chromosomes.
Eggs are made in a similar way in ovaries, and they too are all unique. The real-life mechanics of this mixing are fairly well understood. During the manufacture of a sperm or egg , bits of each paternal chromosome physically detach themselves and change places with exactly corresponding bits of maternal chromosome. Remember that we are talking about chromosomes that came originally from the parents of the individual making the sperm, i.
The process of swapping bits of chromosome is called crossing over. It means that if you got out your microscope and looked at the chromosomes in one of your own sperms or eggs if you are female it would be a waste of time trying to identify chromosomes that originally came from your father and chromosomes that originally came from your mother. Any one chromosome in a sperm would be a patchwork, a mosaic of maternal genes and paternal genes.
The metaphor of the page for the gene starts to break down here. In a loose-leaf binder a whole page may be inserted, removed or exchanged, but not a fraction of a page. But the gene complex is just a long string of nucleotide letters, not divided into discrete pages in an obvious way at all. In between these two punctuation marks are the coded instructions for making one protein.
The word cistron has been used for a unit defined in this way, and some people use the word gene interchangeably with cistron. But crossing-over does not respect boundaries between cistrons. Splits may occur within cistrons as well as between them. It is as though the architect's plans were written out, not on discrete pages, but on 46 rolls of ticker tape. Cistrons are not of fixed length. Crossing-over is represented by taking matching paternal and maternal tapes, and cutting and exchanging matching portions, regardless of what is written on them.
In the title of this book the word gene means not a single cistron but something more subtle. My definition will not be to everyone's taste, but there is no universally agreed definition of a gene. We can define a word how we like for our own purposes, provided we do so clearly and unambiguously. The definition I want to use comes from G. In the words of the previous chapter, a gene is a replicator with high copying-fidelity. The definition will take some justifying.
On any definition, a gene has to be a portion of a chromosome. The question is, how big a portion — how much of the ticker tape? Imagine any sequence of adjacent code-letters on the tape. Call the sequence a genetic unit. It might be a sequence of only ten letters within one cistron; it might be a sequence of eight cistrons; it might start and end in mid-cistron. It will overlap with other genetic units. It will include smaller units, and it will form part of larger units.
No matter how long or short it is, for the purposes of the present argument, this is what we are calling a genetic unit. It is just a length of chromosome, not physically differentiated from the rest of the chromosome in any way. Now comes the important point. The shorter a genetic unit is, the longer — in generations — it is likely to live. In particular, the less likely it is to be split by any one crossing-over.
Suppose a whole chromosome is, on average, likely to undergo one cross-over every time a sperm or egg is made by meiotic division, and this cross-over can happen anywhere along its length. If we consider a very large genetic unit, say half the length of the chromosome, there is a 50 per cent chance that the unit will be split at each meiosis. This means that the unit can expect to survive for a large number of generations in the individual's descendants.
A single cistron is likely to be much less than 1 per cent of the length of a chromosome. Even a group of several neighbouring cistrons can expect to live many generations before being broken up by crossing over. The average life-expectancy of a genetic unit can conveniently be expressed in generations, which can in turn be translated into years.
If we take a whole chromosome as our presumptive genetic unit, its life story lasts for only one generation. Suppose it is your chromosome number 8a, inherited from your father. It was created inside one of your father's testicles, shortly before you were conceived. It had never existed before in the whole history of the world.
It was created by the meiotic shuffling process, forged by the coming together of pieces of chromosome from your paternal grandmother and your paternal grandfather. It was placed inside one particular sperm, and it was unique. This particular sperm unless you are a non-identical twin was the only one of the flotilla which found harbour in one of your mother's eggs — that is why you exist. The genetic unit we are considering, your chromosome number 8a, set about replicating itself along with all the rest of your genetic material.
Now it exists, in duplicate form, all over your body. But when you in your turn come to have children, this chromosome will be destroyed when you manufacture eggs or sperms. The life-span of a chromosome is one generation. This unit too came from your father, but it very probably was not originally assembled in him. Following the earlier reasoning, there is a 99 per cent chance that he received it intact from one of his two parents. Suppose it was from his mother, your paternal grandmother.
Again, there is a 99 per cent chance that she inherited it intact from one of her parents. Eventually, if we trace the ancestry of a small genetic unit back far enough, we will come to its original creator.
At some stage it must have been created for the first time inside a testicle or an ovary of one of your ancestors. The smaller sub-units which make up the genetic unit we are considering may well have existed long before. Our genetic unit was created at a particular moment only in the sense that the particular arrangement of sub-units by which it is defined did not exist before that moment. The moment of creation may have occurred quite recently, say in one of your grandparents.
But if we consider a very small genetic unit, it may have been first assembled in a much more distant ancestor, perhaps an ape-like pre-human ancestor. Moreover, a small genetic unit inside you may go on just as far into the future, passing intact through a long line of your descendants. One of your genetic units may also be present in your second cousin. Time for Action!
Why Choose Us, Readtrepreneur? Lively excerpts from the popular writings of leading theorists in the life sciences blend in a seamless presentation of the controversies and bold ideas driving contemporary biological research. Selections span scales from the biosphere to the cell and DNA, and disciplines from global ecology to behavior and genetics, and also reveals the links between biology and philosophy.
They plunge the reader into debates about heredity and environment, competition and cooperation, randomness and determinism, and the meaning of individuality.
From Gaia to Selfish Genes conveys the technical and conceptual roots of current scientific theories beginning with the planetary perspective of James Lovelock and Lynn Margulis and concluding with the reductionist views of Richard Dawkins and E.
The contrasting worldviews, coupled with excerpts drawn from critics of each theory, encourage readers to examine their own presuppositions. In addition to the scientists' portrayal of the Gaia hypothesis, symbiosis in cell evolution, hierarchy theory, systems theory, game theory, sociobiology, and the selfish gene, the text is rich in autobiographical passages and biographies.
By presenting the human side of research, From Gaia to Selfish Genes reveals the social context and interactions, the motivations and range of cognitive styles that comprise the scientific endeavor. Ford Doolittle, and others underscore the importance of such diversity. Connie Barlow is a science writer currently living in New York City.
The scientists include: Robert Axelrod. Richard D. Ludwig von Bertalanffy. Leo W. Francis Crick. Richard Dawkins. Ford Doolittle. Douglas Hofstadter. Julian Huxley. Leon J.
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