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Erasmus Darwin
Charles Darwin's grandfather - English physician, natural philosopher and physiologist. His poems included much natural history, including a statement of evolution and the relatedness of all forms of life. -
Zoonomia
Eramus Darwin (Charles' grandfather) publishes his scientific work Zoonomia, thought to have been the precursor to the theory of evolution by natural selection. -
Lamarckism
Jean-Baptiste Lamarck publishes Philosophie Zoologique in which he describes his theory of inheritance of acquired characteristics (since disproven). -
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Charles Darwin
Biologist known for his theory of evolution and the process of natural selection. Studied finch populations on the Galapagos islands. -
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Gregor Mendel
Gregor Mendel, scientist and monk, is now recognised as the grandfather of modern genetics. His experiments on pea plants using monohybrid crosses established many of the rules of inheritance, although due to limitations in technology he was unable to identify or explain the mechanism of this phenomena at the time. -
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Alfred Wallace
Independently co-discovered theory of evolution by natural selection. -
On the Origin of the Species
Charles Darwin's book On the Origin of the Species is first published. -
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Theodor Boveri
German biologist, his work with sea urchins was an important part of the Boveri–Sutton chromosome theory. -
Experiments on Plant Hybridisation
Mendel presented his paper on pea plant hybridisation and the theory of inheritance, however his work is largely ignored by the scientific community at the time - partly due to his low-profile as a scientist and partly due to others not understanding his progressive work or its significance. -
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Thomas Hunt Morgan
American evolutionary biologist, geneticist, embryologist, and science author who won the Nobel Prize in Physiology or Medicine in 1933 for discoveries elucidating the role that the chromosome plays in heredity. -
The Geographical Distribution of Animals
Alfred Wallace's book is first published. -
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Walter Sutton
American geneticist and physician whose most significant contribution to present-day biology was his theory that the Mendelian laws of inheritance could be applied to chromosomes at the cellular level of living organisms. -
Grasshopper chromosomes identified
Walter Sutton was studying grasshopper chromosomes which are large and easy to identify. He noted that chromosome numbers are halved in meiosis and the number restored during fertilisation. He also noted that the behaviour of chromosomes during meiosis and fertilisation mirrored the behaviour of Mendel’s factors. -
Boveri's sea urchin experiment
Theodore Boveri had shown in experiments with sea urchins that chromosomes were different from each other, and that the full set of chromosomes was necessary for the normal development of sea urchins from fertilised eggs. He also suggested that Mendel’s ‘factors’ (now called genes) were probably located on the chromosomes. -
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George Wells Beadle
American scientist in the field of genetics, and Nobel Prize in Physiology or Medicine Nobel laureate who with Edward Tatum discovered the role of genes in regulating biochemical events within cells in 1958. -
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Edward Lawrie Tatum
American geneticist who shared half of the Nobel Prize in Physiology or Medicine in 1958 with George Beadle for showing that genes control individual steps in metabolism. -
Drosophila melanogaster (fruit fly) and sex-linkage
Thomas Morgan's research on the fruit fly, chosen for its' rapid breeding in hope of finding mutation for further research. What he discovered instead was a trait that was expressed in non-Mendelian ratios for males and females. He explained these results by suggesting that the gene for eye colour was found on the X chromosome.Morgan showed that genes were located on specific chromosomes and provided supporting evidence for the Boveri and Sutton Chromosome Theory of inheritance. -
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Francis Crick
British molecular biologist, biophysicist, and neuroscientist, most noted for being a co-discoverer of the structure of the DNA molecule in 1953 with James Watson. -
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Maurice Wilkins
New Zealand-born British physicist and molecular biologist, and Nobel laureate, best known for his work at King's College London on the structure of DNA with Rosalind Franklin. -
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Rosalind Franklin
English chemist and X-ray crystallographer who made contributions to the understanding of the molecular structures of DNA (deoxyribonucleic acid), RNA (ribonucleic acid), viruses, coal, and graphite.[2] Although her works on coal and viruses were appreciated in her lifetime, her contributions to the discovery of the structure of DNA were largely recognised posthumously. -
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James Watson (current age: 89)
American molecular biologist, geneticist and zoologist, best known as one of the co-discoverers of the structure of DNA in 1953 with Francis Crick and Rosalind Franklin. -
Beadle and Tatum’s ‘one gene – one protein’ hypothesis
Beadle and Tatum carried out experiments to show the link between genes and enzymes which were thought to be made of proteins. Their experiments involved exposing the bread mold Neurospora crassa to x-rays, causing mutations. -
Discovering DNA Structure
Watson and Crick’s solution was formally announced on April 25, 1953, following publication in Nature magazine. The article revolutionised the study of biology and medicine. Among the developments that followed directly from it were pre-natal screening for disease genes; genetically engineered foods; the ability to identify human remains; the rational design of treatments for diseases such as AIDS; and the accurate testing of physical evidence in order to convict or exonerate criminals.
