Francis Crick

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Francis Crick
Discovery of the DNA Double Helix

Photomontage of Francis Crick lecturing.
Francis Crick James D. Watson
Maurice Wilkins Rosalind Franklin
Linus Pauling Max Delbrück

Professor Francis Harry Compton Crick, OM FRS (8 June 191628 July 2004) was a British physicist, molecular biologist and neuroscientist, most noted for being one of the co-discoverers of the structure of the DNA molecule in 1953, for which he, James Watson and Maurice Wilkins were jointly awarded the 1962 Nobel Prize for Physiology or Medicine.



Born in Northamptonshire, England as a son of Harry and Anne Elisabeth Crick (nee Wilkins), he studied physics at University College London, and obtained a B.Sc. in 1937. During World War II, he worked on the design of magnetic and acoustic mines. He began studying biology in 1947 after the war's end.

Family and education

Crick was born and raised in Weston Favell near the town of Northampton where Crick’s father and uncle ran the family’s boot and shoe factory. At an early age he was attracted to science and what he could learn about it from books. As a child he was taken to church (Congregationalist) by his parents, but by about age 12 he told his mother that he no longer wanted to attend[1]. Crick preferred the scientific search for answers over belief in any dogma. He was educated at Northampton Grammar School (now Northampton School For Boys) and, after the age of 14, Mill Hill School in London (on scholarship) where he studied mathematics, physics and chemistry. At the age of 21, Crick earned a B.Sc. degree in physics from University College London (UCL). Unfortunately he had failed to gain a place at a Cambridge college as he wanted to, probably through falling foul of their requirement for Latin; his British contemporaries in DNA research Rosalind Franklin and Maurice Wilkins both went to Cambridge colleges, i.e. to Newnham and St. John's respectively. Cambridge was to be the subsequent pinnacle of his long scientific career, but he left Cambridge in 1977 after 25 years.

Crick began a Ph.D. research project in the laboratory of physicist Edward Neville da Costa Andrade but with the outbreak of World War II, Crick was deflected from a possible career in physics. After the war, Crick became part of an important migration of physical scientists into biology research. This migration was made possible by the newly won influence of physicists such as John Randall who had helped win the war with inventions like radar. Crick had to adjust from the “elegance and deep simplicity” of physics to the “elaborate chemical mechanisms that natural selection had evolved over billions of years.” He described this transition as, “almost as if one had to be born again.” According to Crick, the experience of learning physics had taught him something important - hubris - and the conviction that since physics was already a success, great advances should also be possible in other sciences like biology. Crick felt that this attitude encouraged him to be more daring than typical biologists who mainly concerned themselves with the daunting problems of biology and not the past successes of physics. For the better part of two years Crick worked on the physical properties of cytoplasm at Cambridge's Strangeways Laboratory, headed by Honor Bridget Fell, with an MRC studentship, until he joined Perutz and Kendrew at the Cavendish. The Cavendish Laboratory at Cambridge was under the general direction of Sir Lawrence Bragg, a Nobel Prize winner at the age of 25 in 1915; Bragg was influential on the determination of DNA's structure to beat the leading American chemist Linus Pauling to the discovery. At the same time Bragg's Cavendish Laboratory was also effectively competing with King's College London under Sir John Randall. (Randall had turned down Francis Crick from working at King's College, London.)

Biology Research

Crick was interested in two fundamental unsolved problems of biology. First, how molecules make the transition from the non-living to the living, and second, how the brain makes mind. He realized that his background made him more qualified for research on the first topic and the field of biophysics. It was at this time of Crick’s transition from physics into biology that he was influenced by both Linus Pauling and Erwin Schrödinger. It was clear in theory that covalent bonds in biological molecules could provide the structural stability needed to hold genetic information in cells. It only remained as an exercise of experimental biology to discover exactly which molecule was the genetic molecule. In Crick’s view, Charles Darwin’s theory of evolution by natural selection, Gregor Mendel’s genetics and knowledge of the molecular basis of genetics, when combined, reveal the secret of life.

It was clear that some macromolecule such as protein was likely to be the genetic molecule. However, it was well known that proteins are “doers”, macromolecules that carry out the many enzymatic reactions of cells. In the 1940’s some evidence had been found pointing to another macromolecule, DNA, the other major component of chromosomes, as a candidate genetic molecule. Oswald Avery and his collaborators showed that a phenotypic difference could be caused in bacteria by providing them with a particular DNA molecule.

An X-ray diffraction image for the protein myoglobin.
An X-ray diffraction image for the protein myoglobin.

However, other evidence was interpreted as suggesting that DNA was structurally uninteresting and possibly just a molecular scaffold for the apparently more interesting protein molecules. Crick was in the right place, in the right frame of mind, at the right time (1949) to join Max Perutz’s project at Cambridge University, and he began to work on the X-ray crystallography of proteins. X-ray crystallography theoretically offered the opportunity to reveal the molecular structure of large molecules like proteins and DNA, but there were serious technical problems then preventing X-ray crystallography from being applicable to such large molecules.

X-ray crystallography 1949-1950

Crick taught himself the mathematical theory of X-ray crystallography. During the time when Crick was learning about X-ray diffraction, researchers in the Cambridge lab were attempting to determine the most stable helical conformation of amino acid chains in proteins (the α helix). Pauling was the first to identify the 3.6 amino acids/turn ratio of the α helix. Crick was witness to the kinds of errors that his co-workers made in their failed attempts to make a correct molecular model of the α helix; these turned out to be important lessons that could be applied to the helical structure of DNA. For example, he learned the importance of the structural rigidity that double bonds confer on molecular structures which is relevant both to peptide bonds in proteins and the structure of nucleotides in DNA.

Francis Crick's first sketch of the deoxyribonucleic acid double-helix pattern
Francis Crick's first sketch of the deoxyribonucleic acid double-helix pattern

The Double Helix 1951-1953

In 1951, together with W. Cochran and V. Vand, Crick helped to work out a mathematical theory of X-ray diffraction by a helical molecule. This theoretical result matched well with X-ray data obtained for proteins that contain sequences of amino acids in the Alpha helix conformation (published in Nature in 1952)[2]. Helical diffraction theory turned out to also be useful for understanding the structure of DNA.

Late in 1951, Crick started working with James D. Watson at Cavendish Laboratory at the University of Cambridge in England. Building on the X-ray diffraction results of Maurice Wilkins, Raymond Gosling and Rosalind Franklin of King's College London, Watson and Crick together developed a model for a helical structure of DNA, which they published in 1953[3], and for which they were awarded the Nobel Prize in Physiology or Medicine in 1962, jointly with Maurice Wilkins[4].

When James Watson came to Cambridge, Crick was a 35 year old graduate student and Watson was only 23, but he already had a Ph.D. They shared an interest in the fundamental problem of learning how genetic information might be stored in molecular form. Watson and Crick talked endlessly about DNA and the idea that it might be possible to guess a good molecular model of its structure. A key piece of experimentally-derived information came from X-ray diffraction images that had been obtained by Maurice Wilkins and his student, Raymond Gosling. In November 1951 Wilkins came to Cambridge and shared his data with Watson and Crick. Alexander Stokes (another expert in helical diffraction theory) and Wilkins (both at at King's College) had reached the conclusion that X-ray diffraction data for DNA indicated that the molecule had a helical structure. Stimulated by Wilkins and a talk given by Rosalind Franklin about her work on DNA, Crick and Watson produced and showed off an erroneous first model of DNA that mainly served to show how little they knew and how desperate they were to solve the structure of DNA. Watson, in particular thought they were competing against Pauling and feared that as for the protein α helix, that Pauling might win the race to determine the structure of DNA.

Many have speculated about what might have happened had Pauling been able to travel to Britain as planned in 1952. He might have seen some of the Wilkins/Gosling/Franklin X-ray diffraction data and it may have led him to a double helix model. As it was, his political activities caused his travel to be restricted by the U. S. government and he did not visit the UK. Watson and Crick were not officially working on DNA. Crick was writing his Ph.D. thesis. Watson also had other work such as trying to obtain crystals of myoglobin for X-ray diffraction experiments. In 1952 Watson did X-ray diffraction on tobacco mosaic virus and found results indicating that it had helical structure. Having failed once, Watson and Crick were now somewhat reluctant to try again and for a while they were forbidden to make further efforts to find a molecular model of DNA.

Of great importance to the model building effort of Watson and Crick was Rosalind Franklin's understanding of basic chemistry which indicated that the hydrophilic phosphate backbones of the nucleotide chains of DNA should be positioned so as to interact with water molecues on the outside of the molecule while the hydrophobic bases should be packed into the core. Franklin shared this chemcal knowledge with Watson and Crick when she pointed out to them that their first model (1951, with the phosphates inside) was obviously wrong.

Crick described the failure of Maurice Wilkins and Rosalind Franklin to cooperate and work towards finding a molecular model of DNA as a major reason why he and Watson eventually made a second attempt to make a molecular model of DNA. They asked for and recieved permission to do so from both Bragg and Wilkins. In order to construct their model of DNA Watson and Crick made use of information from unpublished X-ray diffraction images (shown at meetings and shared by Wilkins) and preliminary accounts of Franklin's detailed analysis of the X-ray images that were included in a written progress report for the King's College laboratory of John Randall from late 1952.

It is a matter of debate if Watson and Crick should have had access to Franklin's results before she had a chance to formally publish the results of her detailed analysis of her X-ray diffraction data that were included in the progress report. In an effort to clarify this issue, Perutz later (June 1960) published what had been in the progress report, showing that nothing was in the report that Franklin herself had not said in her talk (attended by Watson) in late 1951. Further, Perutz explained that the report was to a Medical Research Council committee that had been created in order to "establish contact between the different groups of working for the Council". Randall's and Perutz's labs were both MRC funded laboratories.

It is also not clear how important Franklin's unpublished results that were in the progress report actually were for the model building done by Watson and Crick. After the first crude X-ray diffraction images of DNA were collected in the 1930s, William Astbury had talked about stacks of nucleotides spaced at 3.4 angstrom (0.34 nanometer) intervals in DNA. A citation to Astbury's earlier X-ray diffraction work was one of only 8 references in Franklin's first paper on DNA[5]. Analysis of Astbury's published DNA diffraction data and the better X-ray diffraction images collected by Wilkins, Gosling and Franklin revealed the helical nature of DNA. It was possible to predict the number of bases stacked within a single turn of the DNA helix (10 per turn; a full turn of the helix is 27 angstroms [2.7 nm] in the compact A form, 34 angstroms [3.4 nm] in the wetter B form). Wilkins shared this information about the B form of DNA with Crick and Watson.

One of the few references cited by Watson and Crick when they published their model of DNA was to an published article that included Sven Furberg’s DNA model that had the bases on the inside. Thus, the Watson and Crick model was not the first "bases in" model to be published. Furberg's results had also provided the correct orientation of the DNA sugars with respect to the bases. During their model building, Crick and Watson learned that an antiparallel orientation of the two nucleotide chain backbones worked best to orient the base pairs in the center of a double helix. Crick's access to Franklin's progress report of late 1952 is what made Crick confident that DNA was a double helix with anti-parallel chains, but there were other chains of reasoning and sources of information that also led to these conclusions.

When it became clear to Wilkins and the supervisors of Watson and Crick that Franklin was abandoning her work on DNA for a new job and that Pauling was working on the structure of DNA, they were willing to share Franklin's data with Watson and Crick in the hope that they could find a good model of DNA before Pauling. Franklin's X-ray diffraction data for DNA and her systematic analysis of DNA's structural features was useful to Watson and Crick in guiding them towards a correct molecular model. The key problem for Watson and Crick, that could not be resolved by the data from King's College, was to guess how the nucleotide bases pack into the core of the DNA double helix.

Diagramatic representation of some key structural features of DNA. The similar structures of guanine:cytosine and adenine:thymine base pairs is illustrated. The base pairs are held together by hydrogen bonds. The phosphate backbones are anti-parallel.
Diagramatic representation of some key structural features of DNA. The similar structures of guanine:cytosine and adenine:thymine base pairs is illustrated. The base pairs are held together by hydrogen bonds. The phosphate backbones are anti-parallel.

Another key to finding the correct structure of DNA was the so-called Chargaff ratios, experimentally determined ratios of the nucleotide subunits of DNA: the amount of guanine is equal to cytosine and the amount of adenine is equal to thymine. A visit by Erwin Chargaff to England in 1952 helped keep this important fact in front of Watson and Crick. The significance of these ratios for the structure of DNA were not recognized until Watson, persisting in building structural models, realized that A:T and C:G pairs are structurally similar. In particular, the length of each base pair is the same. The base pairs are held together by hydrogen bonds, the same non-covalent interaction that stabilizes the protein α helix. Watson’s recognition of the A:T and C:G pairs was aided by information from Jerry Donohue[6] about the most likely structures of the nucleobases. After the discovery of the hydrogen bonded A:T and C:G pairs, Watson and Crick soon had their double helix model of DNA with the hydrogen bonds at the core of the helix providing a way to unzip the two complementary strands for easy replication: the last key requirement for a likely model of the genetic molecule. As important as Crick’s contributions to the discovery of the double helical DNA model were, he stated that without the chance to collaborate with Watson, he would not have found the structure by himself.

Crick did tentatively attempt to perform some experiments on nucleotide base pairing, but he was more of a theoretical biologist than one who would perform experiments. There was another close approach to discovery of the base pairing rules in early 1952. Crick had started to think about interactions between the bases. He asked John Griffith to try to calculate attractive interations between the DNA bases from chemical principles and quantum mechanics. Griffith's best guess was that A:T and G:C were attractive pairs. At that time, Crick was not aware of Chargaff's rules and he made little of Griffith's calculations. It did start him thinking about complementary replication. Identification of the correct base-pairing rules (A-T, G-C) was achieved by Watson "playing" with cardboard cutout models of the nucleotide bases, much in the manner that Pauling had discovered the protein alpha helix a few years earlier. The Watson and Crick discovery of the DNA double helix structure was made possible by their correct interpretation of the significance of experimental results that had been obtained by others.

Molecular Biology

Francis Crick also made significant contributions in laying the foundations of the now mature field of molecular biology. This includes work on the nature of the genetic code and the mechanisms of protein synthesis.

After the discovery of the double helix model of DNA, Crick’s interests quickly turned to the biological implications of the structure. In 1953, Watson and Crick published another article in Nature which stated: "it therefore seems likely that the precise sequence of the bases is the code that carries the genetical information"[7].

In 1954, Crick completed his Ph.D. thesis: "X-Ray Diffraction: Polypeptides and Proteins" and received his degree at the age of 37. Crick then worked in the laboratory of David Harker at Brooklyn Polytechnic Institute where he continued to develop his skills in the analysis of X-ray diffraction data for proteins, working primarily on ribonuclease.

Collagen triple helix.
Collagen triple helix.

After his short time in New York, Crick returned to Cambridge where he worked until moving to California in 1976. Crick engaged in several X-ray diffraction collaborations such as one with Alexander Rich on the structure of collagen[8]. However, Crick was quickly drifting away from continued work related to his expertise in the interpretation of X-ray diffraction patterns of proteins.

George Gamow established a group of scientists who were interested in the role of RNA as an intermediary between DNA as the genetic storage molecule in the nucleus of cells and the synthesis of proteins in the cytoplasm. It was clear to Crick that there had to be a code by which a short sequence of nucleotides would specify a particular amino acid in a newly synthesized protein. In 1956 Crick wrote an informal paper about the genetic coding problem for the small group of scientists in Gamow’s RNA group[9]. In this article, Crick reviewed the evidence supporting the idea that there was a common set of about 20 amino acids used to synthesize proteins. Crick proposed that there was a corresponding set of small adaptor molecules that would hydrogen bond to short sequences of a nucleic acid and also link to one of the amino acids. He also explored the many theoretical possibilities by which short nucleic acid sequences might code for the 20 amino acids.

Molecular model of a tRNA molecule. Crick predicted that such adaptor molecules might exist as the links between codons and amino acids.
Molecular model of a tRNA molecule. Crick predicted that such adaptor molecules might exist as the links between codons and amino acids.

During the mid-to-late 1950s Crick was very much intellectually engaged in sorting out the mystery of how proteins are synthesized. By 1958 Crick’s thinking had matured and he could list in an orderly way all of the key features of the protein synthesis process[10]:

  • genetic information stored in the sequence of DNA molecules
  • a “messenger” RNA molecule to carry the instructions for making one protein to the cytoplasm
  • adaptor molecules (“they might contain nucleotides”) to match short sequences of nucleotides in the RNA messenger molecules to specific amino acids
  • ribonucleic-protein complexes that catalyze the assembly of amino acids into proteins according to the messenger RNA

The “adaptor molecules” were eventually shown to be tRNAs and the catalytic “ribonucleic-protein complexes” became known as ribosomes. An important step was later (1960) realization that the messenger RNA was not the same as the ribosomal RNA. None of this, however, answered the fundamental theoretical question of the exact nature of the genetic code. In his 1958 article, Crick speculated, as had others, that a triplet of nucleotides could code for an amino acid. Such a code might be “degenerate”, with 4x4x4=64 possible triplets of the four nucleotide subunits while there were only 20 amino acids. Some amino acids might have multiple triplet codes. Crick also explored other codes in which for various reasons only some of the triplets were used, “magically” producing just the 20 needed combinations. Experimental results were needed; theory alone could not decide the nature of the code. Crick also used the term “central dogma” to summarize an idea that implies that genetic information flow between macromolecules would be essentially oneway:

DNA --> RNA --> Protein. 

Some critics thought that by using the word "dogma" Crick was implying that this was a rule that could not be questioned, but all he really meant was that it was a compelling idea without much solid evidence to support it. In his thinking about the biological processes linking DNA genes to proteins, Crick made explicit the distinction between the materials involved, the energy required and the information flow. Crick was focused on this third component (information) and it became the organizing principle of what became known as molecular biology. Crick had by this time become a dominant, if not the dominant, theoretical molecular biologist.

Proof that the genetic code is a degenerate triplet code finally came from genetics experiments, some of which were performed by Crick[11]. The details of the code came mostly from work by Marshall Nirenberg and others who synthesized synthetic RNA molecules and used them as templates for in vitro protein synthesis[12].

Views on Religion

In his book Of Molecules and Men, Crick expressed his views on the relationship between science and religion[13]. After suggesting that it would become possible for people to wonder if a computer might be programmed so as to have a soul, he wondered: at what point during biological evolution the first organism existed with a soul? At what moment does a baby get a soul? Crick stated his view that the idea of a non-material soul that could enter a body and then persist after death is just that, an imagined idea. For Crick, the mind is a product of physical brain activity and the brain had evolved by natural means over millions of years. Crick felt that it was important that evolution by natural selection be taught in public schools and that it was regrettable that English schools had compulsory religious instruction. Crick felt that a new scientific world view was rapidly being established. Crick predicted that once the detailed workings of the brain were eventually revealed, traditional Western culture, with its foundation formed from erroneous Christian concepts about the nature of man and the world, would no longer be tenable; traditional soul concepts would be replaced by a new understanding of the physical basis of mind.

In October 1969, Crick participated in a celebration of the 100th year of the journal Nature. Crick attempted to make some predictions about what the next 30 years would hold for molecular biology. His speculations were later published in Nature[14]. Near the end of the article, Crick briefly mentioned the search for life on other planets, but he held little hope that extraterrestrial life would be found by the year 2000. He also discussed what he described as a possible new direction for research, what he called "biochemical theology". Crick wrote, "So many people pray that one finds it hard to believe that they do not get some satisfaction from it...."

Crick suggested that it might be possible to find chemical changes in the brain that were molecular correlates of the act of prayer. He speculated that there might be a detectable change in the level of some neurotransmitter or neurohormone when people pray. Crick may have been imagining substances such as dopamine that are released by the brain under certain conditions and produce rewarding sensations. Crick's suggestion that there might some day be a new science of "biochemical theology" seems to have been realized under an alternative name: there is now the new field of Neurotheology[15]. Crick's view of the relationship between science and religion would continue to play a role in his work as he made the transition from molecular biology research into theoretical neuroscience.

Directed Panspermia

During the 1960s Crick became concerned with the origins of the genetic code. In 1966 Crick took the place of Leslie Orgel at a meeting where Orgel was to talk about the origin of life. Crick speculated about possible stages by which an initially simple code with a few amino acid types might have evolved into the more complex code used by existing organisms [16]. At that time, everyone thought of proteins as THE enzymes and ribozymes had not yet been found. Many molecular biologists were worried about the origin of a protein replicating system as complex as what exists in organisms currently living on Earth. In the early 1970s Crick and Orgel further speculated about the possibility that maybe the production of living systems from molecules was a very rare event in the universe, but once it had developed it could be spread by intelligent life forms using space travel technology, a process they called “Directed Panspermia”[17]. In a retrospective article[18], Crick and Orgel noted that they had been overly pessimistic about the chances of life evolving on Earth when they had assumed that some kind of self-replicating protein system was the molecular origin of life. Now it is easier to imagine an RNA world and the origin of life in the form of some self-replicating polymer besides protein.

Results from an fMRI experiment in which people made a conscious decision about a visual stimulus. The small region of the brain colored orange shows patterns of activity that correlate with the decision making process. Crick stressed the importance of finding new methods to probe human brain function.
Results from an fMRI experiment in which people made a conscious decision about a visual stimulus. The small region of the brain colored orange shows patterns of activity that correlate with the decision making process. Crick stressed the importance of finding new methods to probe human brain function.


Starting in 1976, Crick worked at the Salk Institute in La Jolla, California. He taught himself neuroanatomy and studied many other areas of neuroscience research. It took him several years to disengage from molecular biology since exciting discoveries continued including the discovery of alternative splicing and the discovery of restriction enzymes that helped make possible genetic engineering. Eventually, in the 1980s Crick was able to devote his full attention to his other interest, consciousness. His autobiographical book What Mad Pursuit includes a description of why he left molecular biology and switched to neuroscience.

Upon taking up work in theoretical neuroscience, Crick was struck by several things:

  • there were many isolated subdisciplines within neuroscience with little contact between them
  • many people who were interested in behavior treated the brain as a black box
  • consciousness was viewed as a taboo subject by many neurobiologists

Crick hoped he might aid progress in neuroscience by promoting constructive interactions between specialists from the many different subdisciplines concerned with consciousness. He even collaborated with neurophilosophers such as Patricia Churchland. Crick established a collaboration with Christof Koch that lead to publication of a series of articles on consciousness during the period spanning from 1990[19] to 2005. Crick made the strategic decision to focus his theoretical investigation of consciousness on how the brain generates visual awareness within a few hundred milliseconds of viewing a scene. Crick and Koch proposed that consciousness seems so mysterious because it involves very short-term memory processes that are as yet poorly understood. Crick also published a book describing how neurobiology had reached a mature enough stage so that consciousness could be the subject of a unified effort to study it at the molecular, cellular and behavioral levels[20]. Crick's book The Astonishing Hypothesis made the argument that neuroscience now had the tools required to begin a scientific study of how brains produce conscious experiences. Crick was skeptical about the value of computational models of mental function that are not based on details about brain structure and function.

Other Interests

Crick was elected a fellow of CSICOP in 1983 and a Humanist Laureate of the International Academy of Humanism in the same year. In 1995, Francis Crick was one of the original endorsers of the Ashley Montagu Resolution to petition for an end to the genital mutilations of children. Crick died of colon cancer at The University of California, San Diego Thornton Hospital, San Diego.

Reactions to Crick and his Work

Crick has widely been described as talkative, brash and lacking modesty. His personality combined with his scientific accomplishments produced many opportunities for Crick to stimulate reactions from others, both inside and outside of the scientific world that was the center of his intellectual and professional life. It has been suggested that he used small doses of L.S.D. to enhance his scientific discoveries but this has not been formally confirmed.

Religious Beliefs

The conservative political analyst Mark Steyn published a pop psychoanalysis of Crick and an attempted deconstruction of Crick's scientific motivations[21]. Steyn characterized Crick as a militant atheist and asserted that it was his atheism that "drove" Crick to move beyond conventional molecular biology towards speculative topics such as panspermia. Styne described the theory of directed panspermia as amounting to, "gods in the skies who fertilise the earth and then retreat to the heavens beyond our reach." Styne categorized Crick’s ideas on directed panspermia as a result of "hyper-rationalism" that, "lead him round to embracing a belief in a celestial creator of human life, indeed a deus ex machina."

Styne's critique of Crick ignored the fact that Crick never held a belief in panspermia. Crick explored the hypothesis that it might be possible for life forms to be moved from one planet to another. What "drove" Crick towards speculation about directed panspermia was the difficulty of imagining how a complex system like a cell could arise under pre-biotic conditions from non-living chemical components. After ribozymes were discovered, Crick became much less interested in panspermia because it was then much easier to imagine the pre-biotic origins of life as being made possible by some set of simple self-replicating polymers.


It has been observed that Crick would never have concerned himself with panspermia as a possible natural origin of life on Earth if he had simply adopted a belief in intelligent design. However, as a scientist, Crick was concerned with the power of natural processes such as evolution to account for natural phenomena and felt that religiously inspired beliefs are often wrong and cannot be trusted to provide a sound basis for science.

Crick wrote, "The age of the earth is now established beyond any reasonable doubt as very great, yet in the United States millions of Fundamentalists still stoutly defend the naive view that it is relatively short, an opinion deduced from reading the Christian Bible too literally. They also usually deny that animals and plants have evolved and changed radically over such long periods, although this is equally well established. This gives one little confidence that what they have to say about the process of natural selection is likely to be unbiased, since their views are predetermined by a slavish adherence to religious dogmas." (source: The Astonishing Hypothesis)

In a 1987 case before the Supreme Court, Crick joined a group of other Nobel laureates who advised that, "'Creation-science' simply has no place in the public-school science classroom." Crick was also an advocate for the establishment of Darwin Day as a British national holiday.

Drug Use

Rumors have circulated that Crick told a colleague that he had taken small doses of the hallucinogenic drug LSD at the time of the discovery of the structure of DNA in order to boost his deductive powers[22]. However, during his life, Crick was ready to sue anyone who put these rumors into print. Crick was a founding member of a group called SOMA, one of many organizations that has tried to prevent criminalization of cannabis use[23].


  1. ^ Chapters 1 and 2 of What Mad Pursuit: A Personal View of Scientific Discovery by Francis Crick (Basic Books reprint edition, 1990 ISBN 0465091385) provide Crick's description of his early life and education.
  2. ^ See "Evidence for the Pauling-Corey alpha-Helix in Synthetic Polypeptides" (1952) Nature Volume 169 pages 234-235 (download PDF). Crick's scientific publications and letters are in the list of Francis Crick's Papers from the Wellcome Library or the National Library of Medicine.
  3. ^ Molecular structure of Nucleic Acids by James D. Watson and Francis H. C. Crick. Nature 171, 737–738 (1953).
  4. ^ Francis Crick's 1962 Biography from the Nobel foundation.
  5. ^ Franklin's citation to the earlier work of W. T. Astbury is in "Molecular Configuration in Sodium Thymonucleate" by R. Franklin and R. G. Gosling in Nature (1953) volume 171 pages 740-741. The full text of this article is available for download in PDF format.
  6. ^ See Chapter 3 of The Eighth Day of Creation: Makers of the Revolution in Biology by Horace Freeland Judson published by Cold Spring Harbor Laboratory Press (1996) ISBN 0879694785. Judson also lists the publications of W. T. Astbury that described his early X-ray diffraction results for DNA.
  7. ^ "Genetical implications of the structure of deoxyribonucleic acid" by J. D. Watson and F. H. C. Crick (1953) in Nature Volume 171 pages 964-967.
  8. ^ "The structure of collagen" by A Rich and F. H. C. Crick in Nature (1955) Volume 176, pages 915-916.
  9. ^ "On Degenerate Templates and the Adaptor Hypothesis: A Note for the RNA Tie Club" by Francis Crick (1956).
  10. ^ "On protein synthesis" by F. H. C. Crick in Symp Soc Exp Biol. (1958);12:138-63.
  11. ^ "General nature of the genetic code for proteins" by F. H. C. Crick, L. Barnett, S. Brenner and R. J. Watts-Tobin in Nature (1961) Volume 192 pages 1227-1232.
  12. ^ "The Croonian lecture, 1966. The genetic code" by F. H. C. Crick in Proc R Soc Lond B Biol Sci. (1967) Volume 167 pages 331-347.
  13. ^ Of Molecules and Men (Prometheus Books, 2004; original edition 1967) ISBN 1591021855. A portion of the book was published as "The Computer, the Eye, the Soul" in Saturday Review (1966): 53-55.
  14. ^ "Molecular Biology in the Year 2000" by Francis Crick in Nature Volume 228 (1970) pages 613-615.
  15. ^ "The serotonin system and spiritual experiences" by J. Borg, B. Andree, H. Soderstrom and L. Farde in The American Journal of Psychiatry (2003) Volume 160, pages 1965-1969. Entrez PubMed 14594742
  16. ^ "The origin of the genetic code" by F. H. C. Crick in J Mol Biol. (1968) Volume 38 pages 367-379. Entrez PubMed 4887876
  17. ^ "Directed Panspermia” by Francis Crick and Leslie E Orgel in Icarus (1973) Volume 19 pages 341-346. Crick later wrote a book about directed panspermia called Life Itself (Simon & Schuster, 1981) ISBN 0671255622
  18. ^ "Anticipating an RNA world. Some past speculations on the origin of life: where are they today?" by L. E. Orgel and F. H. C. Crick in FASEB J. (1993) Volume 7 pages 238-239.
  19. ^ "Towards a Neurobiological Theory of Consciousness" by Francis Crick and Christof Koch in Seminars in the Neurosciences (1990): Volume 2 pages 263-275.
  20. ^ The Astonishing Hypothesis: The Scientific Search For The Soul by Francis Crick. (Scribner reprint edition, 1995) ISBN 0684801582
  21. ^ See The Twentieth-Century Darwin by Mark Steyn published in The Atlantic Monthly October 2004. Crick's description of his religious views (as given in What Mad Pursuit, see Chapter 1 of reference #1, above) after having told his mother that he no longer wished to attend church services: "...from then on I was a skeptic, an agnostic with a strong inclination toward atheism."
  22. ^ Online at Nobel Prize genius Crick was high on LSD when he discovered the secret of life by Alun Rees.
  23. ^ "The Times Advertisment and the Wooton Report" by Steve Abrams.

Books by Francis Crick

  • Of Molecules and Men (Prometheus Books, 2004; original edition 1967) ISBN 1591021855
  • Life Itself (Simon & Schuster, 1981) ISBN 0671255622
  • What Mad Pursuit: A Personal View of Scientific Discovery (Basic Books reprint edition, 1990) ISBN 0465091385
  • The Astonishing Hypothesis: The Scientific Search For The Soul (Scribner reprint edition, 1995) ISBN 0684801582

Books about Francis Crick

  • Edward Edelson, Francis Crick And James Watson: And the Building Blocks of Life Oxford University Press, 2000, ISBN 0195139712
  • James D. Watson, The Double Helix: A Personal Account of the Discovery of the Structure of DNA, Atheneum, 1980, ISBN 0689706022 (first published in 1968) is a very readable first hand account of the research by Crick and Watson. The book also formed the basis of the award winning television dramatisation Life Story by BBC Horizon (also broadcast as Race for the Double Helix).
  • Francis Crick and James Watson: Pioneers in DNA Research by John Bankston, Francis Crick and James D. Watson (Mitchell Lane Publishers, Inc., 2002) ISBN 1584151226
    • [(James D. Watson/Watson, James D.)] The Double Helix: A Personal Account of the Discovery of the Structure of DNA; The Norton Critical Edition , which was published in 1980, edited by Gunther S. Stent. This book is strongly recommended for its reviews and papers for anyone interested in the history and philosophy of DNA.

See also

External links

  • Extensive online guide to the life and work of Francis Crick, O.M. compiled by Martin Packer, Birmingham (England):; recollections of Francis Crick (for publication) for the forthcoming biography would be very much appreciated as soon as possible. Details

Listen to Francis Crick and James Watson talking on the BBC in 1962, 1972, and 1974.

    • or more recently: and select on: SA#53 - The Quest for Consciousness - 65 minutes - 62mb a conversation on Consciousness with neurobiologist Francis Crick of the Salk Institute and neurobiologist Christof Koch from Caltech.
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