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330 BCE
Aristotle's Scala Naturae
Marble bust of Aristotle. Roman copy after a Greek bronze original by Lysippus c. 330 BC. Photo by Jastrow, via Wikipedia, Public domain -
Lamarck developed Hypothesis of evolution
Lamarck, developed his own theory of inheritance of acquired characters, pangenesis. The basic concept of inheritance of acquired characters was finally widely rejected in the early 20th century. Lamarck published his theory in 1809. -
The Voyage of the Beagle
HMS Beagle in the Straits of Magellan at Monte Sarmiento, reproduction of R. T. Pritchett's frontispiece from the 1890 illustrated edition of The Voyage of the Beagle. -
evolutionary processes
An illustration from the chapter on the application of natural selection to humans in Wallace's 1889 book Darwinism shows a chimpanzee -
On the Origin of Species
n the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life),[3] published on 24 November 1859, is a work of scientific -
inheritance of traits in pea plants by Gregor Mendel
In his experiments, Mendel was able to selectively cross-pollinate purebred click this icon to hear the preceding term pronounced plants with particular traits and observe the outcome over many generations. This was the basis for his conclusions about the nature of genetic inheritance. -
• The Challenger Oceanography Expedition sails around the world
- The Challenger expedition and the beginning of Oceanography. ... On December 21, 1872 the H.M.S. Challenger sailed from Portsmouth, England, for an epic ... a prolonged voyage of exploration across the oceans of the globe. ... Pacific Ocean representing the deepest places in the Earth's crust, now ...
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Plasmodium falciparum
Plasmodium falciparum is a protozoan parasite, one of the species of Plasmodium that cause malaria. Malaria is caused by an infection with protozoa of the genus Plasmodium. The name malaria, comes from the linkage suggested by Giovanni Maria Lancisi (1717) of malaria with the poisonous vapours of swamps. The parasite was first seen by Laveran on November 6, 1880, at a military hospital in Constantine, Algeria, when he discovered a microgametocyte exflagellating. Patrick Manson (1894) hypothesize -
Theodosius Dobzhansky publishes
Theodosius Dobzhansky (1900–1975), claimed that “evolution” is the cornerstone of biology and is central to understanding both living and extinct organisms (Dobzhansky 1973. -
Hardy and Weinberg equation for determining allele.
Godfrey Hardy and Wilhelm Weinberg went on to develop a simple equation that can be used to discover the probable genotype frequencies in a population and to track their changes from one generation to another. This has become known as the Hardy-Weinberg equilibrium equation (p² + 2pq + q² = 1), -
T. Hunt Morgan discovers sex-linkage
Thomas Hunt Morgan (September 25, 1866 – December 4, 1945) was an American .... The observation of a miniature-wing mutant, which was also on the sex ... Morgan proposed that the amount of crossing over between linked genes differs and .... Thomas Hunt Morgan's discovery was illustrated on a 1989 stamp issued in. -
Neils Bohr develops the Bohr model of atom structure
Bohr was the first to discover that electrons travel in separate orbits around the nucleus and that the number of electrons in the outer orbit determines the properties of an element. -
Frederick Griffith describes the process of transformation
Griffith's experiment, was an experiment done in 1928 by Frederick Griffith. It was one of the first experiments showing that bacteria can get DNA through a process called transformation. Griffith used two strains of Pneumococcus. -
• Theodosius Dobzhansky publishes Genetics and the Origin of Species
n 1937, he published one of the major works of the modern evolutionary synthesis, the synthesis of evolutionary biology with genetics, entitled Genetics and the Origin of Species, which amongst other things, defined evolution as "a change in the frequency of an allele within a gene pool". -
1 gene-1 enzyme hypothesis
The one gene-one enzyme hypothesis is the idea that genes act through the production of ... Thus, Beadle reasoned that each gene was responsible for an enzyme ... Thus Beadle and Tatum brought about a fundamental revolution in our ... In their first Neurospora paper, published in the November 15, 1941, edition of the ... -
Ernst Mayr develops the Biological Species Concept
The species problem is a mixture of difficult related questions that often come up when ... In 1942, Ernst Mayr wrote that, because biologists have different ways of identifying ... that were later more fully developed by Theodosius Dobzhansky and Ernst Mayr, ... Although Mayr promoted the biological species concept for use in ... -
ensatina ring species
1Stebbins, R.C. 1949. Speciation in salamanders of the plethodontid genus Ensatina. University of California Publications in Zoology 48:377-526. -
Barbara McClintock describes transposons
In the late 1940s, Barbara McClintock challenged existing concepts of what ... She summarized her data on the first transposable elements she ... 1951 Cold Spring Harbor Symposium describing her discovery of transposition. -
Miller-Urey experiments
it was conducted in 1952[3] by Stanley Miller, with assistance from Harold Urey, at the University of Chicago and later the University of California, San Diego and published the following year. -
The Hershey–Chase experiments
The Hershey–Chase experiments were a series of experiments conducted in 1952[1] by Alfred Hershey and Martha Chase that helped to confirm that DNA is genetic material -
Rosalind Franklin works with DNA and X-Ray crystallography
This is the X-ray crystallograph pattern of DNA obtained by Rosalind Franklin and Raymond Gosling in 1952. It is know as the B-form. It was clearer than the other X-ray patterns because water was included in the DNA sample. Both James Watson and Francis Crick were struck by the simplicity and symmetry of this pattern. -
double helix model of DNA structure
The discovery in 1953 of the double helix, the twisted-ladder structure of deoxyribonucleic acid (DNA), by James Watson and Francis Crick marked a milestone in the history of science -
• Jacques Cousteau develops SCUBA
Jacques-Yves Cousteau AC was a French naval officer, explorer, conservationist, filmmaker, innovator, scientist, photographer, author and researcher who studied the sea and all forms of life in water. Filmmaker, Military Leader, Scientist, Photographer, Inventor, Explorer (1910–1997 -
• Meselson and Stahl work with DNA replication
Meselson and Stahl tested the hypothesis of DNA replication. They cultured bacteria in a 15N medium. 15N is a heavy isotope of nitrogen so the DNA synthesized is of heavy density. Matthew Meselson and Franklin Stahl's experiments on the replication of DNA, published in PNAS in 1958. -
Endosymbiosis theory
The endosymbiotic theory explains how cells evolved. ... another theory is needed to describe how those primitive cells became more complex. ... First published by Lynn Margulis in the late 1960s, the Endosymbiont Theory ... -
• Nirenberg cracks the genetic code
The Nirenberg and Matthaei experiment was a scientific experiment performed on May 15, 1961, by Marshall W. Nirenberg and his post doctoral fellow, J. Heinrich Matthaei. The experiment cracked the genetic code by using nucleic acid homopolymers to translate specific amino acids. -
Apollo 11 Mission
Apollo 11 was to complete a national goal set by President John F. Kennedy on May 25, 1961: perform a crewed lunar landing and return to Earth. -
• Australopithicus afarensis nicknamed “lucy”
Lucy was discovered in 1974 in Africa, near the village Hadar in the Awash Valley of the Afar Triangle in Ethiopia, by paleoanthropologist Donald Johanson -
The Sanger Technique is developed
Developed by Frederick Sanger and colleagues in 1977, it was the most widely used sequencing method for approximately 39 years. ... The Sanger (chain-termination) method for DNA sequencing. -
Deep sea hydrothermal vents and associated life around them are discovered
A hydrothermal vent is a geyser that is located on the floor of the sea. The first such vent was discovered in 1977 on the floor of the Pacific Ocean. Since then, vents have been discovered at a variety of locations in the Pacific and Atlantic Oceans. The vents tend to be located deep in the ocean. -
Kary Mullis develops Polymerase Chain Reaction
The Polymerase Chain Reaction (PCR) technique, invented in 1985 by Kary. B. Mullis, allowed scientists to make millions of copies of a scarce sample of DNA. The technique has revolutionized many aspects of current research, including the diagnosis of genetic defects and the detection of the AIDS virus in human cells. -
Tommie Lee Andrews is convicted of rape
Tommie Lee Andrews in court during his rape trial in Orlando…. ... Serial rapist Tommie Lee Andrews, the first defendant convicted in the United States using DNA evidence, might soon be a free man. -
reproductive isolation
Reproductive isolation as a consequence of adaptive divergence in Drosophila pseudoobscrura -
Spliceosomes were discovered and described
The spliceosome cuts out introns (green line) and seams together exons (orange and blue tracts) from pre-mRNA (FAS, PKM, and MDM2 shown here) in a variety of different ways. These alternative splicing outcomes can result in proteins with opposing roles in a cell, including signaling cell death or cell protection. Here are a few examples. -
• The Innocence Project is founded
The Innocence Project is a non-profit legal organization that is committed to exonerating wrongly convicted people through the use of DNA testing and to reforming the criminal justice system to prevent future injustice. The Innocence Project was founded in 1992 by Barry Scheck and Peter Neufeld. -
• Dolly the sheep is cloned
Dolly the Sheep. Dolly (July 5, 1996 - February 14, 2003), a ewe, was the first mammal to have been successfully cloned from an adult cell. She was cloned at the Roslin Institute in Midlothian, Scotland, and lived there until her death when she was six years old. Her birth was announced on February 22, 1997. -
Sahelanthropus
he first (and, so far, only) fossils of Sahelanthropus are nine cranial specimens from northern Chad. A research team of scientists led by French paleontologist Michael Brunet uncovered the fossils in 2001, including the type specimen TM 266-01-0606-1. -
Homo denisova fossil discovered
In March 2010, scientists announced the discovery of a finger bone fragment of a juvenile female that lived about 41,000 years ago, found in the remote Denisova cave in the Altai Mountains in Siberia -
Louis Pasteur
Louis Pasteur designed an experiment to test whether sterile nutrient broth could spontaneously generate microbial life. To do this, he set up two experiments. In both, Pasteur added nutrient broth to flasks, bent the necks of the flasks into S shapes, and then boiled the broth to kill any existing microbes. -
Richard L Bible is executed
Richard Bible was executed by lethal injection Thursday morning for the 1988 rape and murder of 9-year-old Jennifer Wilson in Flagstaff. Bible was executed on 6/30/11 -
• CRISPr/CAS 9
CRISPR-Cas9 is a unique technology that enables geneticists and medical researchers to edit parts of the genome? by removing, adding or altering sections of the DNA? sequence. -
Human Genome
Sequencing means determining the exact order of the base pairs in a segment of DN -
Homo denisova fossil discovered
Denisovans are Palaeolithic members of the Homo genus that may belong to a previously unknown species of human. This cave has also been inhabited by Neanderthals and modern humans [Krause et al. 2010]. Since then a tooth and a toe bone have been excavated, thought to belong to the same population. -
Galen of Pergamon describes the human body
The first of the great anatomists was Galen of Pergamon (AD 130-200) who made vast achievements in the understanding of the heart, the nervous system, and the mechanics of breathing. The system of anatomy he developed was so influential that it was used for the next 1400 years.