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318 BCE
Aristotle describes life with the Scala Naturae
Aristotle's "scala naturae", defining the natural ladder, became an organized and detailed categorization of living things. The idea of living things was assigned as a hierarchical position with the use of the metaphorical ladder phrase that would represent their degree of perfection and value. Aristotle placed as god, angels, and human beings as well other living things being placed progressively on lower levels. -
162 BCE
Galen of Pergamon describes the human body
Link: http://www.famousscientists.org/galen/
Aelius Galenus, a prominent Greek physician, surgeon as well a philosopher in the Roman Empire. He had great expertise in anatomy, surgery, pharmacology and therapeutic methods. Being illegal in Rome to dissect humans, Galen would dissect animals and treat the wounded gladiators to gain knowledge about the anatomy of the human body. Even today, practices used by Galen are promoted and recognized to be useful as well being well known. -
Lamarck develops Hypothesis of evolution by means of acquired characteristics
Link: http://evolution.berkeley.edu/evolibrary/article/history_09 Jean- Baptiste Lamarck, a French naturalist, known for his Theory of inheritance of Acquired Characteristics, first presented in 1801. His hypothesis states if an organism changes during life in order to adapt to its environment, those changes pass on to its offspring. He also believed that evolutions happens according to a predetermined plan of results that have already been decided. -
The Voyage of the HMS Beagle
Link: http://www.aboutdarwin.com/voyage/voyage03.html This was a voyage Charles Darwin took with a fairly large crew lead by captain Robert Fitzroy to survey the coast of the lower part of South America. It was planned to last about two years, but lasted up to five years. Darwin came across many discoveries and observations while on his trip. -
Alfred Russel Wallace published ideas of evolutionary processes
Link: http://evolution.berkeley.edu/evolibrary/article/history_14 Alfred Russel Wallace, a British naturalist along with other subjects, but being best known for independently conceiving the ideas and theories for the evolutionary processes through the concept of natural selection. Wallace's research as well works inspired Darwin to create and publish with his own ideas about the Origin of Species later on. -
"The Origin of species by means of Natural Selection" is published
Link: http://www.talkorigins.org/faqs/origin.html Charles Darwin's book on the origin of species is considered to be the build of evolutionary biology. In his work he talks about a theory he had formed, which is Darwinism, which states that all species of organism arise and evolve through the natural selection of small, inherited variations that could increase the specimens ability to compete, survival, and reproduction -
Louis Pasteur refutes spontaneous generation
Link: http://www.talkorigins.org/faqs/abioprob/spontaneous- Before the discovery of microbes, it was widely understood that life came from nothing. The theory being viewed is known as spontaneous generation by the sterilization of cultures and keeping them inclosed from coming in contact with open air. Pasteur's developed that contamination of the media, occurred when being introduced to the outside. He showed that life doesn't arise spontaneously. -
"The Germ Theory of Disease" is published
Link:http://www.sciencemuseum.org.uk/broughttolife/techniques/germtheory The germ theory of disease is about diseases being caused by microorganisms. These small organisms are too small to be seen without magnification, but they can invade the human body, animals, and living hosts. Acceptance brought upon the germ theory is because of Louis Pasteur, who aided the development in microscope techniques by Robert Koch. Koch made the microorganisms appear visible and distinguishable. -
Gregor Mendel publishes works on "inheritance of traits in pea plants"
Link: http://www.famousscientists.org/gregor-mendel/ Gregor Mendel known for being the father of genetics. His fundamental laws of inheritance were discovered by his work on pea plants. Noticing genes came in pairs and inherited by both parents in distinct units. He kept track of differences with the parental genes and how they appeared on the offspring as either showing dominant or recessive traits. His research, formed laws of segregation, dominance, and independent assortment. -
The Challenger Oceanography Expedition sails around the world
Link: http://www.divediscover.whoi.edu/history-ocean/challenger.html Modern oceanography began with the Challenger Expedition between 1872 and 1876. A British Navy corvette was converted into the first dedicated oceanographic ship with its own laboratories, microscopes and other scientific equipment onboard.The expedition revealed the first broad outline of the shape of the ocean basin, including a rise in the middle of the Atlantic Ocean that we now know is the Mid-Atlantic Ridge. -
Plasmodium falciparum is described as the causative agent of malaria
Link: https://www.cdc.gov/malaria/about/history/laveran.html Plasmodium falciparum is a protozoan parasite typically found in the hosts blood that has contracted malaria. In humans this is one species of plasmodium that’s a causative agent for malaria. Normally, transmitted by female anopheles mosquito. A french physician named Charles Louis Alphonse Laveran, first to came across the parasitic protozoan of infected victims contaminated with malaria in 1880. -
Hardy and Weinberg independently develop the Hardy-Weinberg equation for determining allele frequencies in populations
Link: http://anthro.palomar.edu/synthetic/synth_2.htm The Hardy-weinberg equation is essentially allows geneticists to do the same thing for entire populations and was made by G.H Hardy and Wilhelm Weinberg. It comes from a mathematical equation (p² + 2pq + q² = 1) describes the distribution and expression of alleles in the population. Also expresses, conditions under which allele frequencies are to be expected to change. -
T. Hunt Morgan discovers sex-linkage
Link: http://www.biologydiscussion.com/genetics/sex-linked-inheritance-sex-linkage-in-drosophila-and-man-with-diagram/5241 T.H Morgan first found out about sex linkage in Drosophila melanogaster. Sex linkage is a phenotype expression of an allele being directly tied to sex chromosomes. -
Neils Bohr develops the Bohr model of atom structure
Link: http://abyss.uoregon.edu/~js/glossary/bohr_atom.html Bohr proposed his quantized shell model of the atom to explain how electrons can have stable orbits around the nucleus. His starting point was to realize that classical mechanics by itself could never explain the atom's stability. He explained how electrons could jump from one orbit to another only by emitting or absorbing energy in fixed quanta. This was quite similar to the structure of the Solar System. -
Frederick Griffith describes the process of transformation
Link: https://education.llnl.gov/bep/science/10/tLect.html In a series of experiments with Diplococcus pneumonia. Using two strains of Pneumococcus, a bacteria that infects mice. Used type II-S and 11-R strains. During the course of his experiment, a living organism (bacteria) had changed in physical form.The purified extract contained Griffith's "transforming principle". Through biochemical testing, they showed it to be deoxyribonucleic acid (DNA). -
Theodosius Dobzhansky publishes "Genetics and the Origin of Species"
Link: http://www.pnas.org/content/94/15/7691.full The Modern Synthesis of Evolutionary Theory, a book that embodies the important works of the modern evolutionary synthesis. Including and familiarizing the work of the populations genetics to the other biologists, who influenced the appreciation for the genetic basis of evolution. -
Beadle and Tatum publish the 1 gene-1 enzyme hypothesis
Link: http://www.historyofinformation.com/expanded.php?id=4325 Beadle and Tatum's experiments are considered to be the first significant results to be called molecular biology. The one gene-one enzyme hypothesis was proposed by George W.B. and Edward L.T. in 1941. Theory states each gene is directly produced as an single enzyme. Turning consequently affects in an individual metabolic pathway. -
Jacques Cousteau develops SCUBA
Link: https://en.wikipedia.org/wiki/Jacques_Cousteau Jacques Cousteau considered “The father of scuba diving” along with his other achievements. Him and his partner Emillie Gagnan, co-invented a demand valve system that would supply divers with compressed air when they breathed. Naming it Aqua-Lung as it allowed diving to become possible to those who are interested in it. -
Avery, MacLoed and McCarty determine that DNA is the molecule that carries the genetic code
Link:http://www.genomenewsnetwork.org/resources/timeline/1944_Avery.php In 1944, experiments by Oswald T. Avery showed that a nucleic acid, deoxyribonucleic acid (DNA), known to be ubiquitous in organisms, was the chemical basis for specific and apparently heritable transformations in bacteria. They used strands of purified DNA from solutions of the cells components to perform bacterial transformation. The three mean proved that DNA, no protein, is the genetic molecule. -
The first atomic bomb is used in war
Link: http://www.history.com/topics/world-war-ii/bombing-of-hiroshima-and-nagasaki On August 6, 1945, an American B-29 bomber dropped the world’s first deployed atomic bomb over the Japanese city of Hiroshima. Top military commanders favored continuing the conventional bombing of Japan already in effect and following up with a massive invasion, codenamed “Operation Downfall.” -
Ensatina described as a ring species
Link: http://www.actionbioscience.org/evolution/irwin.html Ring species provide unusual and valuable situations in which we can observe two species and the intermediate forms connecting them. Complex forms of a horse shoe shape around the mountains, as well with interbreeding can happen between many populations around it. The Ensatina eschscholtzii subspecies on the western end can’t interbreed with the Ensatina klauberi on the eastern end. -
"Hershey-Chase experiments" are published
Link: http://www.biology-pages.info/H/Hershey_Chase.html The Hershey-Chase experiment was a series of experiments being conducted in 1952 by Alfred Hershey and Martha Chase, who helped determine that DNA is an genetic material. Both displayed that when bacteriophages(composed of DNA and protein) infected bacteria, all the infected cells became radioactive and, didn’t get passed to the next generation. -
Rosalind Franklin works with DNA and X-Ray crystallography and develops “Image 51”
Link: http://www.insight.mrc.ac.uk/2013/04/25/behind-the-picture-photo-51/ Photo 51 is an image of a more hydrated ‘B’ form of DNA taken by Raymond Gosling and Rosalind Franklin on May 1952. The unit was then part of the King’s College campus on the Strand in London and was run by Sir John Randall, who had turned some of the university’s physics department over to studying biological problems. The photo was very important evidence in identifying and determining the structure of DNA. -
Watson and Crick propose the double helix model of DNA structure
Link:https://profiles.nlm.nih.gov/SC/Views/Exhibit/narrative/doublehelix.html In 1953 of the double helix, the twisted-ladder structure of DNA, by James Watson and Francis Crick marked a milestone in the history of science. Maurice Wilkins aided and helped them with their data. The double helix has not only reshaped biology, it has become a cultural icon, represented in sculpture, visual art, jewelry, and toys. The three won the Nobel Prize in 1962. -
"Miller-Urey experiments" published
Link:https://ncse.com/files/pub/creationism/icons/gishlick_icons1.pdf The Millier-Urey experiment’s historic role is in the understanding of the origin of life. The experiments were to determine the use of chemical experiments done by Stanley Miller and Harold Urey. They tried to recreate different conditions that were present throughout the early Earth billions of years ago.Provided new information that led to the advancement of scientific understanding of the origin of life. -
Meselson and Stahl work with DNA replication
Link: http://www.pnas.org/content/101/52/17895.full The double helix, whose form has become the icon of biological research.The model did not gain wide acceptance until the publication of another paper 5 years later. Scientific Revolution of this crowning achievement and outlines its subsequent impact on four decades of DNA replication, recombination, and repair research. -
Nirenberg cracks the genetic code
Link:http://www.genomenewsnetwork.org/resources/timeline/1961_Nirenberg.php In 1961 Marshall Nirenberg, a young biochemist discovered the first "triplet"—a sequence of three bases of DNA. Nirenberg's series of key experiments, carried out initially with German scientist Johann Matthaei, employed test-tube techniques.irenberg and Khorana were awarded the 1968 Nobel Prize, with Robert W. Holley, "for their interpretation of the genetic code and its function in protein synthesis." -
Endosymbiosis is described by Lynn Margulis
The Endosymbiotic Theory was first proposed by Lynn Margulis in the 1960’s. Although now accepted as a well-supported theory, both she and the theory were ridiculed by mainstream biologists for a number of years. Similarities between prokaryotes and organelles, together with their appearance in the fossil record, could best be explained by "endo-symbiosis". -
Apollo 11 lands on the moon
Link: https://www.nasa.gov/mission_pages/apollo/apollo11.html July 20, 1969, mankind was able to take a huge leap towards creating the first spaceflight that successfully and officially put a human on the moon. Which was name Apollo 11. The people that part took were Neil Armstrong, Buzz Aldrin, and Michael Collins. -
CRISPr/CAS 9 is identified and described
Link: https://en.wikipedia.org/wiki/CRISPR It's discovery caused a revolution in science. It was first discovered in the 1970s. Becoming a well identified piece of technology that allows to enable geneticists as well medical researchers to edits parts of the genome. This is done by removing or adding/ altering parts of the DNA sequence. Being the simplest and flexible to a precise method. -
Barbara McClintock describes transposons
Link: http://www.pnas.org/content/109/50/20198.full Transposons constitute more than 65% of our genomes and approximately 85% of the maize genome.McClintock received a number of prestigious awards, including the 1970 National Medal of Science and culminating in an unshared Nobel Prize in Physiology or Medicine in 1983. -
The Sanger Technique is developed
Link: https://www.dnalc.org/view/15479-Sanger-method-of-DNA-sequencing-3D-animation-with-narration.html The Sanger Technique is developed by DNA sequencing based on selective incorporation of chain-terminating dideoxynucleotides by DNA polymerase during vitro DNA replication. The DNA sequencing method developed by Fred Sanger formed basis of automated "cycle” sequencing of today. First was a technique called polymerase chain reaction. The second, an automated method of DNA sequencing -
Ernst Mayr develops the Biological Species Concept
Link: http://www.genetics.org/content/167/3/1041 Ernst Mayr had a deep influence in systematics, systematic nomenclature, evolutionary biology, history of biology, and philosophy of biology. He proposed a biological species concept being widely accepted and it defines as a term of interbreeding. -
Theodosius Dobzhansky publishes “Nothing in Science Makes Sense Except in the Light of Evolution.”
Link:https://www.pbs.org/wgbh/evolution/library/10/2/text_pop/l_102_01.html
Anti-evolutionists mistake, or pretend to mistake, these disagreements as indications of dubiousness of the entire doctrine of evolution. Evolution is a light which illuminates all facts, a trajectory which all lines of though must follow this is what evolution is.Teilhard was a creationist, but one who understood that the Creation is realized in this world by means of evolution. -
Australopithicus afarensis nicknamed “lucy” fossil discovered
Link: http://www.history.com/news/famed-lucy-fossils-discovered-in-ethiopia-40-years-ago Specimen AL 288-, commonly known as “Lucy” was discovered by Donald Johanson and Tom Gray. Upon the grounds in which they found Lucy they also found dozens of intact pieces of leg, pelvis, hand and arm bones as well as a lower jawbone, teeth and part of the skull. All told, the pieces amounted to about 40 percent of what appeared to be at least a three million-year-old hominid skeleton -
Spliceosomes were discovered and described
Link: https://en.wikipedia.org/wiki/Spliceosome A spliceosome is a large and complex molecular machine found primarily within the splicing speckles of the cell nucleus of eukaryotic cells. It’s created from snRNAs and protien complexes. Removes introns from a transcribes pre-mRNA. This whole ordeal is normally known as “splicing" -
Deep sea hydrothermal vents and associated life around them are discovered
Link: http://nationalgeographic.org/media/deep-sea-hydrothermal-vents/ Discovering deep sea hydrothermal vents they also realized that an entirely unique ecosystem, involving hundreds of new species existed around the vents. They can be found near active volcano sites, places where tectonic plates move, and etc... -
Kary Mullis develops Polymerase Chain Reaction
Link: https://www.karymullis.com/pcr.shtml Polymerase chain reaction defines as a technique that grants scientist to take on millions of duplicates from a scarce sample of DNA. The technique developed by Kary Mullis who in which was a Nobel prize winner as he was working as a chemist. With the technique that was being used in hand allowed the use of thermocycling to quickly copy segments of DNA. -
Tommie Lee Andrews is convicted of rape
Link: http://articles.orlandosentinel.com/2012-08-03/news/os-dna-tommie-lee-andrews-release-20120803_1_serial-rapist-tommie-lee-andrews-dna-evidence Serial rapist Tommie Lee Andrews, first defendant convicted in the United States using DNA evidence. With the police sending to semen and blood samples over to a New York lab since they have came into conclusion that both cases do share some similarities. The lab will then look over the DNA and compare them to the crime scene samples. -
Richard L Bible is executed
Link: http://www.clarkprosecutor.org/html/death/US/bible1259.htm Bible was released from prison after serving a sentence imposed in 1981 for kidnapping and sexual assault.n his last words, he made no mention of the crime for which he was put to death. Richard L. "Ricky" Bible, 49, of Flagstaff, was pronounced dead by lethal injection at 11:11 a.m. -
“Reproductive isolation as a consequence of adaptive divergence in Drosophila pseudoobscrura” published.
Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3539013/ The focus of speciation research in recent years has gradually shifted from broad geography-based models of sympatry versus allopatry toward understanding the mechanisms that give rise to reproductive isolation potentially resulting in speciation. Diane M.B. is the creator for the findings about fruit flies. -
The Innocence Project is founded
Link: http://www.truthinjustice.org/ips.htm The Innocence Projects provide representation and/or investigative assistance to prison inmates who claim to be innocent of the crimes for which they were convicted. It was founded in 1992 by Barry Scheck and Peter Neufeld. -
Dolly the sheep is cloned
Link: http://www.animalresearch.info/en/medical-advances/timeline/cloning-dolly-the-sheep/ Dolly the sheep, as the first mammal to be cloned from an adult cell, is by far the world's most famous clone. To produce Dolly, scientists used an udder cell from a six-year-old Finn Dorset white sheep. They had to find a way to 'reprogram' the udder cells - to keep them alive but stop them growing – which they achieved by altering the growth medium. -
Sahelanthropus tchadensis fossil discovered
Link: http://humanorigins.si.edu/evidence/human-fossils/species/sahelanthropus-tchadensis Sahelanthropus tchadensis is one of the oldest known species in the human family tree. This species lived sometime between 7 and 6 million years ago in West-Central Africa.The foramen magnum is located further forward than in apes or any other primate except humans. -
Human genome is fully sequenced
Link: https://www.genome.gov/11006943/human-genome-project-completion-frequently-asked-questions/ The human genome contains approximately 3 billion base pairs, which reside in the 23 pairs of chromosomes within the nucleus of our cells. The volunteers gave blood samples after being counseled and then giving their informed consent. About 5 to 10 times as many volunteers donated blood as were eventually used, so that not even the volunteers would know whether their sample was used. -
Homo denisova fossil discovered
Link: http://www.talkorigins.org/faqs/homs/denisova.html The Denisovan individual differed from modern humans by an average of 385 positions. Being discovered at the Denisova Cave in the Altai mountains in southern Siberia. Fossils of large molar teeth were unknown at the time by December 2010 remains of an ancient homo genus species and were named Denisovans
