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322 BCE
Aristotle describes life with Scala Naturae
The Greek philosopher Aristotle based his ideas on the "Natural ladder," also known as, Scala Naturae, in which the natural world could be arranged in a single continum. In medieval times, this became known as the idea of the Great chain of Being. Information retrieved from: http://palaeos.com/systematics/greatchainofbeing/scala_naturae.html -
160
Galen of Pergamon describes the human body
Galen of Pergamon was able to get a great understanding of the mechanics of breathing, the heart, and the nervous system by dissecting pigs and monkeys. He developed the system of anatomy, which was used for the next 1,300 years -
Alfred Russel Wallace published ideas of evolutionary processes
British biologist Alfred Russel Wallace and Charles Darwin came up with the process of natural selection. Information retrieved from: https://evolution.berkeley.edu/evolibrary/article/history_14 -
Lamarck develops Hypothesis of evolution by means of acquired characteristics
The theory of adaptation also known as the inheritance of acquired characteristics is a hypothesis, in which an organism goes through physiological changes over its life span. Lamarck excepted this theory and used it to further explain how evolution could have taken place. Lamarck went on to incorporate the theory into his own theory and published it in 1809. Information retrieved from: https://en.wikipedia.org/wiki/Inheritance_of_acquired_characteristics -
The Challenger Oceanography Expedition sails around the world
The Challenger Expedition set sail with 243 people, six of which were scientist. The goal was to collect data of the ocean. Information retrieved from: http://www.actforlibraries.org/the-challenger-expedition-shaped-the-science-of-oceanography/ -
The Voyage of the HMS beagle
Charles Darwin wrote a scientific journal about sailing on the ship named The Beagle. The expedition took 5 long years though originally it was suppose to be 2. The ship set sail from Plymouth sound in December 1831. After his return his journal was published into a book called, The Voyage of the HMS Beagle. Information retrieved from: https://en.wikipedia.org/wiki/The_Voyage_of_the_Beagle -
The Germ Theory of Disease is published
IN 1546 the germ theory was proposed by Girolamo Fracastro. It stated that diseases were caused by microorganisms. Information retrieved from: https://en.wikipedia.org/wiki/Germ_theory_of_disease -
Ensatina described as a ring species
The Ensatina subspecies E.e. eschscholtzi, also known as the Monterey Ensatina, is found in Monterey, and California coastal moutains. They can be as long as three to five inches long. As for the Ensatina eschscholtzii, it is know as the ring species and is found in the central Valley of California. Though both are salamaders the may not interbreed. They can be found in moist areas such as under logs, and streams. Information retrieved from:https://en.wikipedia.org/wiki/Ensatina -
The Origin of species by means of Natural Selection is published
On the Origin of species by means of Natural selection or the preservation of favoured races in the struggle for life was published in 1859. The theory by Charles Darwin is considered to be the foundation of evolutionary biology. The evidence presented was diversity of life arose through a branching pattern of evolution by common decent. Information retrieved from: https://en.wikipedia.org/wiki/On_the_Origin_of_Species -
Lois Pasteur refutes spontaneous generation
Refutes spontaneous generation was an experiment to test whether sterile nutrient broth could generate microbial life. Information retrieved from: https://en.wikipedia.org/wiki/Spontaneous_generation -
Plasmodium falciparum is described as the causative agent of malaria
Plasmodium falciparum is described as the deadliest species of Pasmodium. It causes malaria in humans. It can be spread through the bite of a female Anopheles mosquito. It has caused 50% of all malaria cases. Information retrieved from: https://en.wikipedia.org/wiki/Plasmodium_falciparum -
Hardy and Weinberg independendly develope the Hardy-Weinberg equation for determining allele frequencies in popuations
The mathematical equation which describes the expression of alleles and how they are distributed is called the Hardy-Weinberg equilibrium. It is the study of genes defined in a group. The law states that the allele will remain constant in the absence of other evolutionary influences. -
Neils Bohr develops the Bohr model of atom structure
In the Rutherford Bohr model, the atom is shown as a positively charged nucleus, which is small and surrounded by electrons that orbit around the nucleus. -
Frederick Griffith describes the proccess of transfrmation
The first experiment implying bacteria was capable of transferring genetic information was called the Griffith's experiment. Fredrick Griffith came up with the idea to make a vaccine after Pneumonia was causing death during the Spanish influenza pandemic post world war 1. Information retrieved from: https://en.wikipedia.org/wiki/Griffith%27s_experiment -
T. Hunt Morgan discovers sex-linkage
Thomas Hunt Morgan was awarded the Nobel prized for the work on Drosophilia. Morgan was determined to test the idea of inherited chromosomal factors using the flies. After many experiments and much criticism, Morgan found the evidence needed proving that traits could be passed by the inheritance of sex chromosomes. Information retrieved from: https://www.nature.com/scitable/nated/topicpage/thomas-hunt-morgan-and-sex-linkage-452 -
Theodosius Dobzhansky publishes Genetics and the Origin of Species
Theodosius Dobzhansky Ukrainian-American that published the book Genetics and the Origin of species in 1937. The book contained the study of natural populations helping him address evolutionary problems during that time. Information retrieved from: https://en.wikipedia.org/wiki/Genetics_and_the_Origin_of_Species -
Beadle and Tatum publish the 1 gene-1 enzyme hypothesis
George Wells Beadle proposed the theory that each gene makes a single enzyme, which in turn affects an individual step in a metabolic pathway. The theory was called the One gene One enzyme hypothosis. Information retrieved from: https://embryo.asu.edu/pages/george-w-beadles-one-gene-one-enzyme-hypothesis -
Jacques Cousteau develops Scuba
In 1942 Jacques Cousteau and partner Emile Gagan invented a way divers could breath under water with compressed air. This invention of what is called scuba diving has not only helped with raising awareness of different marine life, but has made it possible for others to enter the under water world. Information retrieved from: http://www2.padi.com/blog/2014/01/27/jacques-cousteau-the-father-of-scuba-diving/ -
Avery, MacLoed and McCarty determine that DNA is the molecule that carries the genetic code
In 1944 the Avery-MacLeod-McCarty experiment demonstrated that DNA is the substance that causes bacterial transformation.. Information retrieved from: https://en.wikipedia.org/wiki/Avery%E2%80%93MacLeod%E2%80%93McCarty_experiment -
The first atomic bomb usd in war
The United States dropped an Atomic Bomb of Nagasaki and Hiroshima at the end of World War 2. The bombings killed about 129,000 people. The nuclear war heads were dropped after Japan refused to surrender. Most of the deaths were from casualties. Information retrieved from: https://en.wikipedia.org/wiki/Atomic_bombings_of_Hiroshima_and_Nagasaki -
Barbara McClintock described transposons
The discovery of transposons was made by Barbara McClintock from the 1940 to the 1950 The discovery was used to show that genes are the reason for physical characteristics being turned on and off. Information retrieved from: https://en.wikipedia.org/wiki/Barbara_McClintock -
Hershey-Chase experiments are published
In 1952 Alfred Hershey and Martha Chase confirmed that DNA is a genetic material by conducting experiments. They concluded that protein was not hereditary genetic material but they did not conclude what specific function DNA did have. Once published it led to more experiments on of DNA. Information retrieved from: https://en.wikipedia.org/wiki/Hershey%E2%80%93Chase_experiment -
Miller-Urey experiments published
Miller-Urey experiment was a chemical experiment simulating conditions on early earth, which tested chemical origins of life under certain conditions. The experiment was conducted using H2, H2O, CH4, and NH3. Though he conclusion of amino acid was far less then it really is, his experiment helped to determine that there are actually 20 amino acids. Information retrieved from: Miller-Urey experiments published -
Watson and Crick propose the double helix model of DNA structure
In 1953 James Watson and Francis Crick presented the structure of the DNA-helix. The DNA-helix is a molecule that carries genetic information from one generation to the other. In 1962 they were later awarded the Nobel prize in Physiology.. Information retrieved from: https://www.nobelprize.org/educational/medicine/dna_double_helix/readmore.html -
Meselson and Stahl work with DNA replication
The Meselson-Stahl experiment was conducted by Mathew Meselson and Franklin Stahl, which supported the hypothosis of Watson and Crick, that DNA replication was semiconservative. It was proposed that the two stands in a DNA molecule separate during DNA replication. Later each strand acts as a template for synthesizing a new strand. Information retrieved from: Meselson and Stahl work with DNA replication -
Nirenberg cracks the genetic code
In 1961 Nirenberg and Mathaei conducted an experiment to extract bacterial cells that make protein even when no living cells were present. They added an artificial form of RNA and the experiment cracked the first codon of the genetic code.
Information retrieved from: https://en.wikipedia.org/wiki/Nirenberg_and_Matthaei_experiment -
Rosalind Franklin works with DNA and X-Ray crystallography and develops "Image 51"
Rosalind Franklin was best known for working on the X-Ray diffraction images of DNA. She helped discover the double helix with James Watson, Francis Crick and Mauric Walkins, but was never awarded the Nobel Prize as they did. Information retrieved from: https://en.wikipedia.org/wiki/Rosalind_Franklin -
Gregor Mendel publishes works on inheritance of traits in pea plants
Many of the rues of heredity were established by Gregor Johann Mendel, which is known as Mendelian inheritance. The work he had done with pea plants helped establish that law. The experiments he conducted took place between 1856 and 1963. Information retrieved from: https://en.wikipedia.org/wiki/Gregor_Mendel -
Endosymbiosis is described by Lynn Margulis
In 1966 while Lynn Margulis was a faculty member at Boston University, she wrote a theory caled "On the Origin of mitosing cells." Her paper was rejected 15 times until finaly being accepted by Journal of Theoretical Biology. Today it is a landmark in modern endosymbiotic theory. Information retrieved from: https://en.wikipedia.org/wiki/Lynn_Margulis -
Apollo 11 lands on the moon
In 1969 July 20, Neil Armstrong became the first person to walk on the moon after landing the Apollo 11. Apollo 11 was a space craft that ended the space race by not only landing on the moon but by returning the men back to earth. Information retrieved from: https://en.wikipedia.org/wiki/Apollo_11 -
Homo denisova fossil discovered
The discovery of the Homo sapien found that they are genetically distinc from the Neanderthals, Siberia, southeast Asia and modern day humans. Information retrieved from: https://en.wikipedia.org/wiki/Denisovan -
Theodosius Dobzhansky publishes "Nothing in Biology Makes sense Except in the light of Evolution."
Theodosius Dobzhansky made an essay esousing theistic evolution and criticising anti-evolution creationism. It was published in American Biology Teacher. The statement "Nothing in Biology Makes Sense except in the Light of Evolution," was first used during a presidential address in 1964. Information retrieved from: https://en.wikipedia.org/wiki/Nothing_in_Biology_Makes_Sense_Except_in_the_Light_of_Evolution -
Austalopithicus afarensis nicknamed "Lucy" fossil discovered
Paleothropologist Donald Johanson came across partial remains in Ethiopia. The skeleton was nick named "Lucy" and it is said that the ape-like hominoid walked upright like humans and was estimated to be 3.2 million years old. Information retrieved from: http://www.history.com/news/famed-lucy-fossils-discovered-in-ethiopia-40-years-ago -
Spliceosomes were discovered and described
Spliceosomes were discovered to be large RNA-protein complexes that mediate nuclear pre-mRNA splicing between 1976 and 1985. Information retrieved from: https://www.news-medical.net/life-sciences/RNA-Discovery.aspx -
Deep sea hydrothermal vents and associated life around them are discovered
Scientist made a discovery after wondering how the temperatures in the ocean could change so drastically. To their surprise after exploring, they found that there were deep sea hydrothermal vents. Information retrieved from: https://www.nationalgeographic.org/media/deep-sea-hydrothermal-vents/ -
The Sanger Technique is developed
Sanger Sequencing was developed by Frederick Sanger and his colleagues in 1977 and has since been used. Information retrieved from: https://en.wikipedia.org/wiki/Sanger_sequencing -
Kary Mullis develops Polymerase Chain reaction
Polymerase Chain reaction was made by Kary Mullis, in order to make a faster way of coping a segment of DNA, through orders of magnitude, generating thousands to millions of copies of a certain DNA sequence. Information retrieved from:https://en.wikipedia.org/wiki/Polymerase_chain_reaction -
Reproductive isolation as a consequence of adaptive divergence in Drosphila pseudoobscrura. uahost.uantwerpen.be/funmorph/raoul/CNO/Dodd1989.pdf
A study done by Diane M.B. Dodd on speciation being a problem of reproductive isolation. The ways classified were premating isolation. This is when mating is prevented from happening or if it does happen, the offspring are not to be produced and post mating should be done. The results concluded that inforcement of premating isolation mechanisms through selection is not needed for behavioral isolation Information retrieved from: uahost.uantwerpen.be/funmorph/raoul/CNO/Dodd1989.pdf -
CRIPr/CAS 9 identified and described
Clustered Regulary Interspaced Short Palindromic Repeats is a deffence system in Prokaryotic immune system that provide immunity by resisting foreign genetic elements. Information retrieved from: https://en.wikipedia.org/wiki/CRISPR -
Richard L Bible is executed
Richard L. Bible was executed for being found guilty of the 1988 molestation, kidnapping and murder of the 1 Jennifer Wilson. DNA evidence was used to put criminal charges against Bible and was the first time DNA evidence was used in Arizona. In April 1990, Bible was convicted and sentenced to death. Information retrieved from: http://victimsfamiliesforthedeathpenalty.blogspot.com/2013/06/in-loving-memory-of-jennifer-wilson.html -
The Innocence project is founded
The Innocence Project helps people who have been convicted of a crime they did not commit by the use of DNA. The non-profit legal organization uses the DNA to prove the innocence of a person wrongfully convicted or to exonerate some one from a crime they have not done. Information retrieved from: https://en.wikipedia.org/wiki/Innocence_Project -
Dolly the sheep is cloned
Dolly was a female sheep that was the first mammal to be cloned from the somatic cell of an adult, using the process of nuclear transfer. Information retrieved from: https://en.wikipedia.org/wiki/Dolly_(sheep) -
Tommie Lee Andrews is convicted of rape
For the first time in U.S history, DNA was introduced successfully into evidence. Serial rapist Tommy Lee Andrews was convicted and sentenced to 22 years in prison after being found guilty of burglary, aggravated battery and rape. Information retrieved from: http://articles.latimes.com/1997-03-02/local/me-33996_1_serial-rapist -
Human genome is fully sequenced
The methods used in the 1970's and 1980's were manual, but by the 90's it became automated which allowed whole genomes to be sequenced. The shift helped human chromosomes 22. The first human genomes sequenced were two Americans. Information retrieved from: https://en.wikipedia.org/wiki/Human_Genome_Project -
Sahelanthropus tchadenis fossil discovered
The remains of the Sahelanthropus tchadenis fossil was discovered between July 2001 and March 2002. Just the top part( head) was found and the rest of the body was never discovered. The tchadensis is believed to be in between the time chimpanzee evolved into humans. Information retrieved from: https://en.wikipedia.org/wiki/Sahelanthropus
