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160 BCE
Galen of Pergamon describes the human body
Galen was a prominent Greek physician, surgeon, and philosopher in the Roman Empire. He was the first of the great anatomists (AD 130-200), first performing anatomy on Barbary apes. -
410
Aristotle describes like with the Scala Naturae
a Greek philosopher and scientist Aristotle described the Scala Naturae which is a strict, religious hierarchical structure of all matter and life, believed to have been decreed by God due to evolution. It was strongly associated with the ideas of divine order, perfection, continuity, and gradualism. -
Lamarck develops Hypothesis of evolution
Lamarck developed the hypothesis that If an organism changes during life in order to adapt to its environment, those changes are passed on to its offspring in 1801. -
The Voyage of the HMS Beagle
The Voyage of the Beagle is the title most commonly given to the book written by Charles Darwin and published in 1839 as his Journal and Remarks, bringing him considerable fame and respect. -
Louis Pasteur refutes spontaneous generation
The theory of spontaneous generation which is an incorrect hypothesis that nonliving things are capable of producing life was refuted by Louis Pasterur in 1859. He boiled a meat broth in a flask that had a long neck that curved downward, like that of a goose or swan. The idea was that the bend in the neck prevented falling particles from reaching the broth, while still allowing the free flow of air. -
The Origin of species by means of Natural Selection is published
On the Origin of Species, published on 24 November 1859, is a work of scientific literature by Charles Darwin which is considered to be the foundation of evolutionary biology. -
The Germ Theory of Disease is published
The more formal experiments on the relationship between germ and disease were conducted by Louis Pasteur between 1860 and 1864. He discovered the pathology of the puerperal fever and the pyogenic vibrio in the blood, and suggested using boric acid to kill these microorganisms before and after confinement. -
Gregor Mendel publishes works on inheritance of traits in pea plants
Mendel's pea plant experiments conducted between 1856 and 1863 established many of the rules of heredity, now referred to as the laws of Mendelian inheritance.He published his work in 1866. -
• “Reproductive isolation as a consequence of adaptive divergence in Drosophila pseudoobscrura”
the two main ways to classify isolation are premating isolation, and postmating isolation. to study the process of the development of reproductive isolation, eight populations of Drosophila pseudoobscrura were studied and it has been noted an increase in fast alle of ammy in the starch populations and increase in one of the patterns of amylase activity. -
Plasmodium falciparum is described as the causative agent of malaria
A parasite was first seen by Laveran on November 6, 1880, at the military hospital in Constantine, Algeria, when he discovered a microgametocyte ex flagellating. Then Patrick Mason (1894) hypothesized that mosquitoes could transmit malaria. This hypothesis was experimentally confirmed independently by Giovanni Battista Grassi and Ronald Ross in 1898. -
Neils Bohr develops the Bohr model of atom structure
Bohr proposed his quantized shell model of the atom to explain how electrons can have stable orbits around the nucleus. This was a stability problem, so the remedy to the problem, Bohr modified the Rutherford model by requiring that the electrons move in orbits of fixed size and energy.
Works cited: www.wikipedia.com -
Hardy and Weinberg independently develop the Hardy-Weinberg equation for determining allele frequencies in populations
Bohr proposed his quantized shell model of the atom to explain how electrons can have stable orbits around the nucleus. This was a stability problem, so the remedy to the problem, Bohr modified the Rutherford model by requiring that the electrons move in orbits of fixed size -
T. Hunt Morgan discovers sex-linkage
In 1915, Morgan and his colleagues published “The Mechanism of Mendelian Heredity.” And one of its major tenets was, ‘certain characteristics are sex-linked—that is occur together because they arise on the same chromosome that determines gender. -
Frederick Griffith describes the process of transformation
Griffith did experiment in 1928 on mouse. he mixed heat-killed S with live R and injected the combination into mice and then the mouse died. He concluded that something in the heat-killed S bacteria “transformed.” -
Theodosius Dobzhansky publishes Genetics and the Origin of Species
Genetics and the Origin of Species is a 1937 book by Theodosius Dobzhansky. It is regarded as one of the most important works of the modern evolutionary synthesis. -
Beadle and Tatum publish the 1 gene-1 enzyme hypothesis
The one gene-one enzyme hypothesis is the idea that genes act through the production of enzymes, with each gene responsible for producing a single enzyme that in turn affects a single step in a metabolic pathway. The concept was proposed by George Beadle and Edward Tatum in an influential 1941 paper on genetic mutations in the mold Neurospora crassa. -
Jacques Cousteau develops SCUBA
Cousteau played a huge role in the development of modern scuba diving. he developed the modern demand regulator and an improved autonomous diving suit In 1942. -
Ernst Mayr develops the Biological Species Concept
Ernst Mayr approached Charles Darwin’s species problem with a new definition for species in his book “Systematics and the Origin of Species”. he wrote that a species is not just a group of morphologically similar individuals, but a group that can breed only among themselves, excluding others. -
Avery, MacLoed and McCarty determine that DNA is the molecule that carries the genetic code
The Avery–MacLeod–McCarty experiment was an experimental demonstration, reported in 1944 by Oswald Avery, Colin MacLeod, and Maclyn McCarty, 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. -
Ensatina described as a ring species
in 1947, Robert suggested that Ensatina species started off in Northern California and Oregon and then spread south along both sides of the Central Valley. Robert came up with a hypothesis that stated that as the pioneering populations moved south, they evolved to several subspecies with new color patterns and adaptations. -
Barbara McClintock describes transposons
She was an American scientist and cytogeneticist who discovered transposition and used it to demonstrate that genes are responsible for turning physical characteristics on and off. Because of her work, transposons are now a hot favorite among biologists in the field of gene. -
Miller-Urey experiments
the Miller-Urey experiment demonstrated how some biological molecules, such as simple amino acids, could have arisen abiotically, that is through non-biological processes, under conditions thought to be sim-ilar to those of the early earth. -
Hershey-Chase experiments
Hershey and Chase experiments showed that when bacteriophages, which are composed of DNA and protein, infect bacteria, their DNA enters the host bacterial cell, but most of their protein does not. -
Rosalind Franklin works with DNA and X-Ray crystallography and develops “Image 51”
Photo 51,the nickname given to an X-ray diffraction image of DNA taken by Raymond Gosling in May 1952 became a crucial data source that led to the development of the DNA model and confirmed the prior postulated double helical structure of DNA. -
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. -
Alfred Russel Wallace published ideas of evolutionary processes
Alfred Wallace wrote an essay to Darwin in 1858 that wallace's theories of natural selection and Darwin published his theories of natural selection attached with assay. -
Meselson and Stahl work with DNA replication
This was an experiment by matthew Meselson and Canadian biologist, Mason McDonald, and Canadian nuclear physicist, Amandeep Sehmbi, in 1958 which supported the hypothesis that DNA replication was semiconservative. (when the double stranded DNA helix is replicated, each of the two new double-stranded DNA helices consisted of one strand from the original helix and one newly synthesized. -
Nirenberg cracks the genetic code
In a 1961 experiment by Marshall Nirenberg looked at how DNA directs protein synthesis and the role of RNA in these processes. he used RNA strand that contained only U. -
Endosymbiosis is described by Lynn Margulis
Margulis, a prolific writer and dynamic speaker, wrote her first article on the endosymbiotic theory in 1967, brought her to the forefront of the controversy over cellular -
Apollo 11 lands on the moon
Apollo 11 was the first spaceflight that landed humans on the Moon. Mission commander Neil Armstrong and pilot Buzz Aldrin landed the lunar module Eagle on July 20, 1969 -
Theodosius Dobzhansky publishes “Nothing in Science Makes Sense Except in the Light of Evolution.”
Theodosius Dobzhansky had major influence on the 20th century through and research on genetics and evolutionary theory. he criticized anti-evolution creationism and espousing theisticevolution in his essay in 1973. -
The Challenger Oceanography Expedition sails around the world
The Challenger expedition of 1872-76 was a scientific exercise that made many discoveries to lay the foundation of oceanography. It was described as “the greatest advance in the knowledge of our planet since the celebrated discoveries of the fifteenth and sixteenth centuries. She traveled nearly 70,000 nautical miles (130,000 km) surveying and exploring. -
The Sanger Technique is developed
The Sanger Technique was developed by Frederick Sanger in 1977 to determine the order of bases in a strand of DNA. -
Deep sea hydrothermal vents and associated life around them are discovered
In 1977, scientists exploring the Galapagos Rift along the mid-ocean ridge in the eastern Pacific noticed a series of temperature spikes in their data. They wondered how deep-ocean temperatures could change so drastically-from near freezing 400 degrees C (750 degrees F) in such a short distance. This discovery was – deep-sea hydrothermal vents. -
Australopithicus afarensis nicknamed “lucy” fossil discovered
A new species name, Australopithecus afarensis, was created for in 1978. This species is now represented by several hundred fossils from east Africa. 'Lucy'AL 288-1 -
Kary Mullis develops Polymerase Chain Reaction
He was a Nobel Prize-winning American biochemist, author, and lecturer. Mullis was driving his vehicle late one night with his girlfriend, who was also a chemist at Cetus, when he had the idea to use a pair of primers to bracket the desired DNA sequence and copy it using DNA polymerase. He succeeded in demonstrating PCR December 16, 1983. -
Tommie Lee Andrews is convicted of rape
Through DNA fingerprints, a jury found Andrews guilty as a convicted serial rapist. This case is significant because this case ended with the first American trial to admit DNA typing into evidence. -
Richard L Bible is executed
Arizona executed 49-year-old Richard Lynn Bible for molesting and fatally bludgeoning 9-year-old Jennifer Wilson in 1988. He asked the U.S. Supreme Court to delay his execution for DNA testing on hairs used as evidence in his trial. -
The Innocence Project is founded
The Innocence Project, founded is non-profit legal organization was founded in 1992 and it helps wrongly convicted people through DNA testing. -
CRISPr/CAS 9 is identified and described
Francisco Mojca was the first researcher to identify and describe the term CRISPr in 1993. -
Dolly the sheep is cloned
Dolly was a female domestic sheep, and the first mammal cloned from an adult somatic cell, using the process of nuclear transfer. She was born on 5, July 1996 and had three mothers. (one provided the egg, another the DNA and a third carried the cloned embryo to term. -
Spliceosomes were discovered and described
A spliceosome is a large and complex molecular machine found primarily within the splicing speckles of the cell nucleus of eukaryotic cells. The spliceosome is assembled from snRNAs and protein complexes. -
Sahelanthropus tchadensis fossil discovered
The first fossils of Sahelanthropus are nine cranial specimens from northern Chad.a research by Michael Brunet and his team uncovered the fossils in 2001, including the type specimen. -
Human genome is fully sequenced
the idea of the human genome projects was to determine the sequence of nucleotide base pairs and understanding the human genome from both physical and functional standpoint. the project was launched in 1990 and was declared complete in 2003. -
Homo denisova fossil discovered
homo denisovans are an extinct species of human in the genus homo. In March 2010, scientists announced the discovery of a finger bone fragment of a juvenile female who lived about 41,000 years ago, found in the remote Denisova Cave in the Altai Mountains in Siberia, a cave that has also been inhabited by Neanderthals and modern humans