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130 BCE
Galen of Pergamon describes the Human Body
Galen was the greatest physician. He developed its own theory and practice. He was a master in the medical philosophy. He had three chef contributions to the theory of the Greek medicine. The three theories were pneuma, or vital energy and the four facilities of the organism. He had a famous formula called Theriac, it was an herbal jam. It had 64 different ingredients that was panacea, it cured for all diseases. -
Alfred Russel Wallace published Ideas of Evolutionary Processes
It was Darwin's genius both to show how all this evidence favored the evolution of species from a common ancestor and to offer a plausible mechanism by which life might evolve. But in the mid-1800s, Darwin and the British biologist Alfred Russel Wallace independently conceived of a natural, even observable, way for life to change: a process Darwin called natural selection.In this struggle for existence, survival and reproduction do not come down to pure chance. -
Lamarck Developed Hypothesis of Evolution by means of Acquired Characteristics
Modifications acquired by an organism can be inherited by the offspring. Acquired characteristics are those changes in the structure or function of an organism that are the result of use, disuse, environmental influences, disease, mutilation such as a muscle that is enlarged through use or mice that have their tails cut off. The theory of the inheritance of acquired characteristics holds that an organism experiencing such a modification can transmit such a character to its offspring. -
The Germ Theory of Disease is published
Germ theory states that many diseases are caused by the presence and actions of specific micro-organisms within the body. The laboratory researches of Louis Pasteur in the 1860s and then Robert Koch in the following decades provided the scientific proof for germ theory. -
Gregor Mendel published Works on Inheritance of Traits in Pea Plants
Gregor Mendel, through his work on pea plants, discovered the fundamental laws of inheritance. He deduced that genes come in pairs and are inherited as distinct units, one from each parent. Mendel tracked the segregation of parental genes and their appearance in the offspring as dominant or recessive traits -
The Origin of Species by means of Natural Selection is Published
Charles Darwin published the origin of species after two decades of research. He traveled all around South America unpaid just to get information. Darwin became an outstanding researcher and scientific writer based on his many papers and letters dispatched from South America and Galapagos islands. -
Louis Pasteur Refutes Spontaneous Generation
Spontaneous generation is an obsolete body of thought on the ordinary formation of living organisms without descent from similar organisms. It is an experiment to test whether sterile nutrient broth could spontaneously generate microbial life. He set up two experiments. -
The Voyage of the Beagle
Charles Darwin was invited on a ship called the Hms by captain Robert Fitzroy. The trip was supposed to last 2 years but ended up lasting 5 years. Darwin published a book in 1839 and did a republication in 1905. The book was about species, evolution, common descent, and natural selection and also included some of his ideas. -
Hardy and Weinberg independently develop the Hardy-Weinberg equation for determining allele frequencies in populations - 1908
The Hardy-Weinberg equation is the mathematical equation that can be used to calculate the genetic variation of a population at equilibrium. In 1908, G.H. Hardy and Wilhelm Weinberg independently described a basic principle of population genetics, which is now named the Hardy -
T. Hunt Morgan discovers Sex-Linkage
Thomas Hunt Morgan establishes the chromosomal theory of heredity. Some links sexual characteristics appear together as they arise on a chromosome determines gender. Genes close together tend to come together. But sometimes, as a consequence of the reproductive mechanism, the link between the genes is disrupted, allowing new combinations of traits. -
Bohr model
Atomic physics, the Rutherford–Bohr model or Bohr model or Bohr diagram, introduced by Niels Bohr and Ernest Rutherford in 1913, depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus. -
Frederick Griffith describes the Process of Transformation
In the critical experiment, Frederick Griffith (1928) mixed heat-killed S with live R and injected the combination into mice: the mouse died. The dead mouse’s tissues were found to contain live bacteria with smooth coats like S. These bacteria were subsequently able to kill other mice, and continued to do so after several generations in culture. He concluded that something in the heat-killed S bacteria “transformed.” -
Barbara McClintock describes Transposons
Barbara McClintock in the late 1940s challenged existing concepts of what genes were capable off when she discovered some genes could be mobile (transposons). With Barbara’s studies of chromosomes breakage in maize let to her to discover that a chromosome breaking locus that could change its positions within a chromosome. -
Beadle and Tatum Publish the 1 Gene-1 Enzyme Hypothesis
The one gene–one enzyme hypothesis, proposed by George Wells Beadle in the US in 1941, is the theory that each gene directly produces a single enzyme, which consequently affects an individual step in a metabolic pathway. In 1941, Beadle demonstrated that one gene in a fruit fly controlled a single, specific chemical reaction in the fruit fly, which one enzyme controlled. -
Ernst Mayr develops the Biological Species Concept
Ernst Mayr solved one great-unsolved problem in Darwin's work: How and why do species originate? When a population of organisms becomes separated from the main group by time or geography, they eventually evolve different traits and can no longer interbreed. This isolation or separation creates new species. -
Jacques Cousteau Develops
Several scuba suits were designed before Cousteau came up with a successful suit. What led him to create a suit was that he was in an almost fatal accident that broke both of is arms. He spent his recovery time in the Mediterranean sea which led him to wonder what was unexplored of the natural world and decided to make a proper suit for scuba diving so he teamed up with Emile Gagnan (and engineer) and made it happen by 1943. -
Avery, MacLeod and McCarty determined that DNA is the Molecule that Carries the Genetic Code
That DNA is the substance that causes bacterial transformation, in an era when it had been widely believed that it was proteins that served the function of carrying genetic information. -
Miller-Urey Experiments published
Miller and Urey conducted an experiment which demonstrated several compounds that could be formed spontaneously by stimulating the conditions of earths early atmosphere. They used gases like the ones fond in the earths early atmosphere. The experiment showed evidence that the first life forms arose from these chemicals though the theory has many skeptical. -
Watson and Crick Propose the 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 and gave rise to modern molecular biology, which is largely concerned with understanding how genes control the chemical processes within cells. -
Rosalind Franklin works with DNA and X-Ray crystallography and develops “Image 51”
Image 51 was the nickname that was given to an X-ray diffraction image of DNA taken by Raymond Gosling in May 1952, Raymond was a PhD student that was under the supervision of Rosalind Franklin, at King's College London in Sir John Randall's group. This breakthrough was groundbreaking as it proved many theories on the DNA’s structure. -
Hershey-Chase Experiment are Published
Alfred Hershey believed that proteins were more likely to be the carriers of genetic information the opposite of the Avery-MacLeod experiments Hershey teamed up with Martha Chase and tracked the transfer of proteins and DNA between a virus. They found that DNA were the carriers of genetic information but they were the first to prove it. -
Meselson and Stahl work with DNA replication
Meselson and Stahl proposed a semi conservative hypothesis. About two strands of DNA molecule separate during replication. Then each template acts as a template and for synthesis of a new strand. The semi conservative hypothesis predicts that after a replication it will contain one new and old strand. -
Endosymbiosis is described by Lynn Margulis
In the late 1960s Lynn Margulis studied the structure of cells. Right after the modern synthesis established that natural selection act up on mutations could generate new adaptations and new species. Researchers asked if the new lineages and adaptations only branch off from the old ones and inherited new genes from the old linage. Some of the researchers said no. Lynn Margulis showed that the major organizational involved the merging of two or more linages through symbiosis. -
Nirenberg Cracks the Genetic Code
Marshall Nirenberg discovered the first "triplet"—a sequence of three bases of DNA that codes for one of the twenty amino acids that serve as the building blocks of proteins. Protein synthesis takes place in the cytoplasm, where RNA is found. RNA provided the key to the code. The protein molecule is then built by adding one amino acid at a time, using the mRNA as a template. -
Kary Mullis develops Polymerase Chain Reaction
During the symposium held for centenarian Albert Holfmann, he revealed that he was told from Nobel prize winning from the chemists Kary Mullis that LSD helped him developed the polymerase chain reaction that helps amplify specific DNA sequences. -
Theodosius Dobzhansky publishes “Nothing in Science Makes Sense Except in the Light of Evolution"
He was an Ukrainian-American geneticist and evolutionist whose work had a major influence on 20th century thought and research on genetics and evolutionary theory. He wrote this essay in 1973, criticizing anti-evolution creationism and espousing theistic evolution. -
Australopithecus Afarensis nicknamed “Lucy” Fossil Discovered
While hunting for fossils in Ethiopia’s Afar Triangle on November 24, 1974, paleoanthropologist Donald Johanson and graduate student Tom Gray stumbled upon the partial remains of a previously unknown species of ape-like hominid. -
Theodosius Dobzhansky publishes Genetics and the Origin of Species
Theodosius Dobzhansky was the author of Modern Synthesis of Evolutionary Theory. Genetics and the Origin of Species is just rewritten formulas and theories from famous biologist in language that biologists could understand, dressed the equations with natural history and experimental population genetics, and extended the synthesis to specialization and other cardinal problems omitted by the mathematicians. -
Spliceosomes were Discovered and Described
The discovery of “split genes” in 1977 was absolutely breathtaking. They wondered, “How could this be?” This amazing sequence arrangement spurred a thrilling and highly competitive search of mechanism. -
Deep Sea Hydrothermal Vents and Associated Life Around them are Discovered
The scientists discovered sea deep hydrothermal vents. They discovered that there is a unique ecosystem. There is hundreds of species that exist around the vents. Despite the temperatures, deep temperatures, and toxic mineral and lack of sunlight. Scientists discovered that bacteria were converting toxic vent minerals form useable forms energy through a process that is called chemosynthesis that provide food for the other vent organisms. The Hydrothermal vents are like geysers. -
The Sanger Technique
Frederick Sanger who invented the method of DNA sequencing by enzymes, now known as the Sanger method, to determine the order of bases in a strand of DNA. This method helps scientists can read the sequence of nucleotide in a DNA molecule. -
Tommie Lee Andrews is Convicted of Rape
On Feb 5, 1988, a jury had convicted Andrews of rape on the basis of the DNA ''fingerprint'' of his blood. On May 9, 1986, Andrews was broken into the home of a woman, raped and stabbed her. He had said that he had never left his apartment the night this woman was attacked. However, an expert in genetics analysis had testified that the DNA ''fingerprint'' of Andrews' blood matched that of the rapist's semen. -
Richard L. Bible is Executed
Ricky was sentenced for execution after 23 years and five days for Jenifer’s Wilson’s murder. Her body was found on Sheep Hill. Ricky was put to death. He was pronounced dead by lethal injection at 11:11 am. On July 1, 2011 at the Arizona Department of Corrections Central Unit. Jenifer had more than 40 witnesses before Ricky’s death. Bible only had two witness and it was his two attorneys’. -
The Innocence Project
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. -
CRISPr/CAS 9 is Identified and Described
Francisco Mojca was the first researcher to characterize what is now called CRISPr locus, reported in 1993. He worked on them throughout the 1990’s and in 2000, he recognized that what had been reported as disparate repeat sequences, (he coined the term CRISPr through correspondence with Ruud Jansen. -
Dolly the Sheep is Cloned
Dolly, a Finn Dorset sheep, was born by cloning. Dolly was the world's first mammal to be cloned successfully from an adult cell. Dolly's birth and subsequent survival proved that adult cells can reprogram themselves into a new being. -
Sahelanthropus Tchadensis
A fossil was found by scientist and hey decided to name it Sahelanthropus Tchadensis. Scientist say is has animal and human features. A face like an ape and walked up right like humans. Different scientist looked at it and they believed it survived in different habitats like in forests and grasslands. A lot of features are not yet determined. -
Human Genome's Fully Developed
The human genome project sequence is how they determined the exact order of the base pairs in a segment of DNA. A rough draft was presented in the white house on June 26, 2000 but was not fully developed until this day. Humans have about 50,000,000 to 300,000,000 base pairs. Bases exist in pairs, the identity of one pair determines the other member of the pair and scientist do not have to determine the bases. -
Homo Denisova Fossil Discovered
A small fossil that was later found to be a finger belonging to either a neutral or a modern human the finger bone was then titled X-woman X for being unknown and woman for containing mt-DNA even though males also contain Mt-DNA meaning this finger either belonged to a male or female.
