Scientists Through History provides a timeline of famous scientists and their accomplishments, including:
- Aristotle established the foundations of taxonomy and defined nature's scale.
- Leonardo da Vinci studied anatomy extensively and tried to recreate bird flight.
- Antony van Leeuwenhoek invented the simple microscope and was the first to observe bacteria and other microorganisms.
- Robert Hooke coined the term "cell" after observing cork under the microscope and made other advances in physics.
- Charles Darwin developed the theory of evolution by natural selection, providing a mechanism by which species evolved over generations.
2. Aristotle
Classification of nature into groups, subgroups,
and gave birth to the profession of taxonomy.
Blooded (vertebrates)
Bloodless (invertebrates)
He created Nature’s scale and defined nature
purpose: Inanimate to Living Beings (possibility
of changing) to Plants and Living beings
(mobile).
Worked out the hydrologic cycle
Described life cycles, species only born from
same and reproduce the same.
3. Leonardo da Vinci
Determined tree’s age by the # of rings in
the trunk
Studied Anatomy Extensively
Studied heart and eye extensively
Tried to recreate birds flight.
Was the first one to propose a theory
about the creation of fossils.
4. Antony van Leeuwenhoek
First Simple Microscope
First to observed unicellular organisms
Able to calculate the size of bacteria, protozoa,
sperm cells, stripped muscles and blood cells.
He built simple microscopes by grinding lenses
He laid the foundations of the detailed
observation of the microscopic organisms
Discovered capillary systems
Opposed the theory of spontaneous generation,
proved this by showing fleas and mussels came
from eggs
5. Robert Hooke (XVIIc)
Published Microgaphia which is a record
of his observations in microscopic
organisms.
Devised compound microscope
Observed and coined the term cells, in
cork.
Numerous other advances in Physics
6. Sir. Francis Bacon
Change in way of thinking
Substituted Aristotle’s deductive reasoning
(general to particular) for an inductive
reasoning (particular to general) (Novum
Organum) nowadays known as the
Scientific Method
First to develope Scientific Method
7. Nicholas Steno
Made observations on the anatomy of the brain.
First one to show that the heart has two independent
pumps
Discovered that fossils are petrified plants and animals
Established some of the fundamental principles of
stratigraphy. Rocks form in horizontal positions
Law of Original Horizontality (Rock formed in Horizontal
Layers)
Law of Supperposition
First use of geology by saying the rocks were divided by
layers from different times.
8. Francesco Redi
Italian physician and poet.
Redi demonstrated in 1668 that rotting
meat carefully kept from flies will not
produce maggots, providing experimental
evidence against the theory of
spontaneous generation.
9. George Cuvier
Studied natural history and comparative
anatomy
Function determines form, as a theory of
evolution.
Established extinction as fact.
Animals were immutable.
Classified animals by their skeletal structure
Vertebrata
Articulata
Radiata
Mollusca
10. Carolus Linnaeus
Considered the father of taxonomy
Several expeditions in Sweden
Created a binomial system for naming
species
Studied hyloridization
Binomial nomenclature (genus then
species)
11. Lazaro Spallanzani (1729-1799)
An Italian naturalist, philosopher, and
priest
Described the regeneration of organs in
such animals as worms, snails, and frogs.
He attempted to induce frogs’ eggs to
develop artificially by using vinegar and
lemon juice
12. Thomas Malthus
English Economist
Theories on population
Plants arithmatic growth
Animals geometric growth
Relation of Food and Sex to populations – Positive
Relation of Vice and Mersery to populations – Negative
No perfect society,
Darwin’s Statements about Malthus’s work – the
strongest will survive
Mathus said that man will overpopulate the earth
13. Jean-Baptiste Lamarck
Theory of evolution based on the use and
lack of use of some organs
An organ is used becomes stronger then
this characteristic will be passes on to
offspring
Heredity
First to use term Biology
Theory of Transmutation – aquired traits
can be inherited.
14. Adam Sedgwick
Explored geology of Scotland and presented his
research
Proposed a new division of the geological
timescale (the Devonian and the Cambrian)
Published “On the Silvarian and Cambrian
systems, exhibiting the order in which the older
sedimentary strata suceed each other in
England and Wales”
Strata, same strata exist separated in space but
representing the same time.
Taught Darwin about Geology.
15. Joseph Mendel
Studied botanics
Used garden peas to study heredity
Established the laws of segregation and independent
assortment.
First person to trace characteristics of succesive
generations.
Published experiments with Plants (Hybrids)
Heredity character are independent
They combine at random
Characters dominant or recessive
Antagonistic heredity factors never transmitted together
16. Thomas Henry Huxley
He supported the theory of evolution of Darwin
and convinced people to accept it
First teacher of biology to use the laboratory
method.
Supported Darwin’s theories
Punctuated evolution as opposed to Darwin,
Gradual
I would rather be a man decended from apes
than one afraid to face the truth
Jellyfish microbes in embryos of other organisms
17. Louis Pasteur
Found Vaccines for – rabies, anthrax (sheep),
chicken cholera, silk worm diseases
Discovered- germ theory, spontaneous
generation (living things from non-living)
proposed and disproved
Created – First vaccines, pasteurization (heat
killing organisms in milk), immunization
Gave birth to – stereochemistry, microbiology,
bacteriology, virology
18. Watson and Crick
Proposed the double helical structure of
DNA
Analyzed and studied the structure of
molecules that transmit the genetic
characteristics from one generation to the
next.
X ray defraction used to desifer structure
of DNA.
19. Oparin
1) Formation of the planet with gases in the
atmosphere that could serve as the raw materials for
life. The most widely accepted astronomical theory
for the origin of the earth and the rest of the solar
system is that the solar system formed about 4.5
billion years ago from a diffuse dust cloud.
2) Random synthesis of simple organic molecules
(such as amino acids that make up proteins) from
the gases in the surrounding atmosphere.
3) Formation of larger, more complex molecules
(Macromolecules) from the simple organic
molecules, e.g., the formation of simple proteins.
20. Oparin cont
4) Formation of coacervates - unique droplets containing the
macromolecules , i.e., a coacervate consists of chemicals
suspended within a liquid surrounded by a membrane, e.g. a
droplet consisting of chemicals in water surrounded by an oil
layer membrane.
5) Development of some type of chemical organizers that
function to give these droplets the ability to take in molecules,
discharge other molecules, and control and maintain a
characteristic chemical pattern.
6) Development of controlled reproduction to insure that
resultant daughter cells have the same chemical capabilities.
7) Beginnings of evolutionary developments so that a group of
cells could adapt to changes in the environment over time.
21. Sir Alexander Fleming (1881 -
1955)
Fleming had discovered the first antibiotic,
penicillin
However, it was not until the research
work of Florey and Chain that penicillin
could be produced as a drug.